diff --git a/container/garray/garray_normal_any.go b/container/garray/garray_normal_any.go
index 616a59062..985c02fc7 100644
--- a/container/garray/garray_normal_any.go
+++ b/container/garray/garray_normal_any.go
@@ -30,7 +30,7 @@ type Array struct {
 }
 
 // New creates and returns an empty array.
-// The parameter <safe> is used to specify whether using array in concurrent-safety,
+// The parameter `safe` is used to specify whether using array in concurrent-safety,
 // which is false in default.
 func New(safe ...bool) *Array {
 	return NewArraySize(0, 0, safe...)
@@ -42,7 +42,7 @@ func NewArray(safe ...bool) *Array {
 }
 
 // NewArraySize create and returns an array with given size and cap.
-// The parameter <safe> is used to specify whether using array in concurrent-safety,
+// The parameter `safe` is used to specify whether using array in concurrent-safety,
 // which is false in default.
 func NewArraySize(size int, cap int, safe ...bool) *Array {
 	return &Array{
@@ -51,8 +51,8 @@ func NewArraySize(size int, cap int, safe ...bool) *Array {
 	}
 }
 
-// NewArrayRange creates and returns a array by a range from <start> to <end>
-// with step value <step>.
+// NewArrayRange creates and returns a array by a range from `start` to `end`
+// with step value `step`.
 func NewArrayRange(start, end, step int, safe ...bool) *Array {
 	if step == 0 {
 		panic(fmt.Sprintf(`invalid step value: %d`, step))
@@ -66,18 +66,20 @@ func NewArrayRange(start, end, step int, safe ...bool) *Array {
 	return NewArrayFrom(slice, safe...)
 }
 
+// NewFrom is alias of NewArrayFrom.
 // See NewArrayFrom.
 func NewFrom(array []interface{}, safe ...bool) *Array {
 	return NewArrayFrom(array, safe...)
 }
 
+// NewFromCopy is alias of NewArrayFromCopy.
 // See NewArrayFromCopy.
 func NewFromCopy(array []interface{}, safe ...bool) *Array {
 	return NewArrayFromCopy(array, safe...)
 }
 
-// NewArrayFrom creates and returns an array with given slice <array>.
-// The parameter <safe> is used to specify whether using array in concurrent-safety,
+// NewArrayFrom creates and returns an array with given slice `array`.
+// The parameter `safe` is used to specify whether using array in concurrent-safety,
 // which is false in default.
 func NewArrayFrom(array []interface{}, safe ...bool) *Array {
 	return &Array{
@@ -86,8 +88,8 @@ func NewArrayFrom(array []interface{}, safe ...bool) *Array {
 	}
 }
 
-// NewArrayFromCopy creates and returns an array from a copy of given slice <array>.
-// The parameter <safe> is used to specify whether using array in concurrent-safety,
+// NewArrayFromCopy creates and returns an array from a copy of given slice `array`.
+// The parameter `safe` is used to specify whether using array in concurrent-safety,
 // which is false in default.
 func NewArrayFromCopy(array []interface{}, safe ...bool) *Array {
 	newArray := make([]interface{}, len(array))
@@ -98,8 +100,15 @@ func NewArrayFromCopy(array []interface{}, safe ...bool) *Array {
 	}
 }
 
+// At returns the value by the specified index.
+// If the given `index` is out of range of the array, it returns `nil`.
+func (a *Array) At(index int) (value interface{}) {
+	value, _ = a.Get(index)
+	return
+}
+
 // Get returns the value by the specified index.
-// If the given <index> is out of range of the array, the <found> is false.
+// If the given `index` is out of range of the array, the `found` is false.
 func (a *Array) Get(index int) (value interface{}, found bool) {
 	a.mu.RLock()
 	defer a.mu.RUnlock()
@@ -120,7 +129,7 @@ func (a *Array) Set(index int, value interface{}) error {
 	return nil
 }
 
-// SetArray sets the underlying slice array with the given <array>.
+// SetArray sets the underlying slice array with the given `array`.
 func (a *Array) SetArray(array []interface{}) *Array {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -128,7 +137,7 @@ func (a *Array) SetArray(array []interface{}) *Array {
 	return a
 }
 
-// Replace replaces the array items by given <array> from the beginning of array.
+// Replace replaces the array items by given `array` from the beginning of array.
 func (a *Array) Replace(array []interface{}) *Array {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -152,7 +161,7 @@ func (a *Array) Sum() (sum int) {
 	return
 }
 
-// SortFunc sorts the array by custom function <less>.
+// SortFunc sorts the array by custom function `less`.
 func (a *Array) SortFunc(less func(v1, v2 interface{}) bool) *Array {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -162,7 +171,7 @@ func (a *Array) SortFunc(less func(v1, v2 interface{}) bool) *Array {
 	return a
 }
 
-// InsertBefore inserts the <value> to the front of <index>.
+// InsertBefore inserts the `value` to the front of `index`.
 func (a *Array) InsertBefore(index int, value interface{}) error {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -175,7 +184,7 @@ func (a *Array) InsertBefore(index int, value interface{}) error {
 	return nil
 }
 
-// InsertAfter inserts the <value> to the back of <index>.
+// InsertAfter inserts the `value` to the back of `index`.
 func (a *Array) InsertAfter(index int, value interface{}) error {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -189,7 +198,7 @@ func (a *Array) InsertAfter(index int, value interface{}) error {
 }
 
 // Remove removes an item by index.
-// If the given <index> is out of range of the array, the <found> is false.
+// If the given `index` is out of range of the array, the `found` is false.
 func (a *Array) Remove(index int) (value interface{}, found bool) {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -247,14 +256,14 @@ func (a *Array) PushRight(value ...interface{}) *Array {
 }
 
 // PopRand randomly pops and return an item out of array.
-// Note that if the array is empty, the <found> is false.
+// Note that if the array is empty, the `found` is false.
 func (a *Array) PopRand() (value interface{}, found bool) {
 	a.mu.Lock()
 	defer a.mu.Unlock()
 	return a.doRemoveWithoutLock(grand.Intn(len(a.array)))
 }
 
-// PopRands randomly pops and returns <size> items out of array.
+// PopRands randomly pops and returns `size` items out of array.
 func (a *Array) PopRands(size int) []interface{} {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -272,7 +281,7 @@ func (a *Array) PopRands(size int) []interface{} {
 }
 
 // PopLeft pops and returns an item from the beginning of array.
-// Note that if the array is empty, the <found> is false.
+// Note that if the array is empty, the `found` is false.
 func (a *Array) PopLeft() (value interface{}, found bool) {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -285,7 +294,7 @@ func (a *Array) PopLeft() (value interface{}, found bool) {
 }
 
 // PopRight pops and returns an item from the end of array.
-// Note that if the array is empty, the <found> is false.
+// Note that if the array is empty, the `found` is false.
 func (a *Array) PopRight() (value interface{}, found bool) {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -298,7 +307,7 @@ func (a *Array) PopRight() (value interface{}, found bool) {
 	return value, true
 }
 
-// PopLefts pops and returns <size> items from the beginning of array.
+// PopLefts pops and returns `size` items from the beginning of array.
 func (a *Array) PopLefts(size int) []interface{} {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -315,7 +324,7 @@ func (a *Array) PopLefts(size int) []interface{} {
 	return value
 }
 
-// PopRights pops and returns <size> items from the end of array.
+// PopRights pops and returns `size` items from the end of array.
 func (a *Array) PopRights(size int) []interface{} {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -337,8 +346,8 @@ func (a *Array) PopRights(size int) []interface{} {
 // Notice, if in concurrent-safe usage, it returns a copy of slice;
 // else a pointer to the underlying data.
 //
-// If <end> is negative, then the offset will start from the end of array.
-// If <end> is omitted, then the sequence will have everything from start up
+// If `end` is negative, then the offset will start from the end of array.
+// If `end` is omitted, then the sequence will have everything from start up
 // until the end of the array.
 func (a *Array) Range(start int, end ...int) []interface{} {
 	a.mu.RLock()
@@ -364,7 +373,7 @@ func (a *Array) Range(start int, end ...int) []interface{} {
 }
 
 // SubSlice returns a slice of elements from the array as specified
-// by the <offset> and <size> parameters.
+// by the `offset` and `size` parameters.
 // If in concurrent safe usage, it returns a copy of the slice; else a pointer.
 //
 // If offset is non-negative, the sequence will start at that offset in the array.
@@ -471,7 +480,7 @@ func (a *Array) Contains(value interface{}) bool {
 	return a.Search(value) != -1
 }
 
-// Search searches array by <value>, returns the index of <value>,
+// Search searches array by `value`, returns the index of `value`,
 // or returns -1 if not exists.
 func (a *Array) Search(value interface{}) int {
 	a.mu.RLock()
@@ -506,7 +515,7 @@ func (a *Array) Unique() *Array {
 	return a
 }
 
-// LockFunc locks writing by callback function <f>.
+// LockFunc locks writing by callback function `f`.
 func (a *Array) LockFunc(f func(array []interface{})) *Array {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -514,7 +523,7 @@ func (a *Array) LockFunc(f func(array []interface{})) *Array {
 	return a
 }
 
-// RLockFunc locks reading by callback function <f>.
+// RLockFunc locks reading by callback function `f`.
 func (a *Array) RLockFunc(f func(array []interface{})) *Array {
 	a.mu.RLock()
 	defer a.mu.RUnlock()
@@ -522,16 +531,16 @@ func (a *Array) RLockFunc(f func(array []interface{})) *Array {
 	return a
 }
 
-// Merge merges <array> into current array.
-// The parameter <array> can be any garray or slice type.
+// Merge merges `array` into current array.
+// The parameter `array` can be any garray or slice type.
 // The difference between Merge and Append is Append supports only specified slice type,
 // but Merge supports more parameter types.
 func (a *Array) Merge(array interface{}) *Array {
 	return a.Append(gconv.Interfaces(array)...)
 }
 
-// Fill fills an array with num entries of the value <value>,
-// keys starting at the <startIndex> parameter.
+// Fill fills an array with num entries of the value `value`,
+// keys starting at the `startIndex` parameter.
 func (a *Array) Fill(startIndex int, num int, value interface{}) error {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -549,7 +558,7 @@ func (a *Array) Fill(startIndex int, num int, value interface{}) error {
 }
 
 // Chunk splits an array into multiple arrays,
-// the size of each array is determined by <size>.
+// the size of each array is determined by `size`.
 // The last chunk may contain less than size elements.
 func (a *Array) Chunk(size int) [][]interface{} {
 	if size < 1 {
@@ -571,9 +580,9 @@ func (a *Array) Chunk(size int) [][]interface{} {
 	return n
 }
 
-// Pad pads array to the specified length with <value>.
+// Pad pads array to the specified length with `value`.
 // If size is positive then the array is padded on the right, or negative on the left.
-// If the absolute value of <size> is less than or equal to the length of the array
+// If the absolute value of `size` is less than or equal to the length of the array
 // then no padding takes place.
 func (a *Array) Pad(size int, val interface{}) *Array {
 	a.mu.Lock()
@@ -608,7 +617,7 @@ func (a *Array) Rand() (value interface{}, found bool) {
 	return a.array[grand.Intn(len(a.array))], true
 }
 
-// Rands randomly returns <size> items from array(no deleting).
+// Rands randomly returns `size` items from array(no deleting).
 func (a *Array) Rands(size int) []interface{} {
 	a.mu.RLock()
 	defer a.mu.RUnlock()
@@ -642,7 +651,7 @@ func (a *Array) Reverse() *Array {
 	return a
 }
 
-// Join joins array elements with a string <glue>.
+// Join joins array elements with a string `glue`.
 func (a *Array) Join(glue string) string {
 	a.mu.RLock()
 	defer a.mu.RUnlock()
@@ -675,8 +684,8 @@ func (a *Array) Iterator(f func(k int, v interface{}) bool) {
 	a.IteratorAsc(f)
 }
 
-// IteratorAsc iterates the array readonly in ascending order with given callback function <f>.
-// If <f> returns true, then it continues iterating; or false to stop.
+// IteratorAsc iterates the array readonly in ascending order with given callback function `f`.
+// If `f` returns true, then it continues iterating; or false to stop.
 func (a *Array) IteratorAsc(f func(k int, v interface{}) bool) {
 	a.mu.RLock()
 	defer a.mu.RUnlock()
@@ -687,8 +696,8 @@ func (a *Array) IteratorAsc(f func(k int, v interface{}) bool) {
 	}
 }
 
-// IteratorDesc iterates the array readonly in descending order with given callback function <f>.
-// If <f> returns true, then it continues iterating; or false to stop.
+// IteratorDesc iterates the array readonly in descending order with given callback function `f`.
+// If `f` returns true, then it continues iterating; or false to stop.
 func (a *Array) IteratorDesc(f func(k int, v interface{}) bool) {
 	a.mu.RLock()
 	defer a.mu.RUnlock()
@@ -784,7 +793,7 @@ func (a *Array) FilterEmpty() *Array {
 	return a
 }
 
-// Walk applies a user supplied function <f> to every item of array.
+// Walk applies a user supplied function `f` to every item of array.
 func (a *Array) Walk(f func(value interface{}) interface{}) *Array {
 	a.mu.Lock()
 	defer a.mu.Unlock()
diff --git a/container/garray/garray_normal_int.go b/container/garray/garray_normal_int.go
index 10dbe16fe..05a10f0fe 100644
--- a/container/garray/garray_normal_int.go
+++ b/container/garray/garray_normal_int.go
@@ -28,14 +28,14 @@ type IntArray struct {
 }
 
 // NewIntArray creates and returns an empty array.
-// The parameter <safe> is used to specify whether using array in concurrent-safety,
+// The parameter `safe` is used to specify whether using array in concurrent-safety,
 // which is false in default.
 func NewIntArray(safe ...bool) *IntArray {
 	return NewIntArraySize(0, 0, safe...)
 }
 
 // NewIntArraySize create and returns an array with given size and cap.
-// The parameter <safe> is used to specify whether using array in concurrent-safety,
+// The parameter `safe` is used to specify whether using array in concurrent-safety,
 // which is false in default.
 func NewIntArraySize(size int, cap int, safe ...bool) *IntArray {
 	return &IntArray{
@@ -44,8 +44,8 @@ func NewIntArraySize(size int, cap int, safe ...bool) *IntArray {
 	}
 }
 
-// NewIntArrayRange creates and returns a array by a range from <start> to <end>
-// with step value <step>.
+// NewIntArrayRange creates and returns a array by a range from `start` to `end`
+// with step value `step`.
 func NewIntArrayRange(start, end, step int, safe ...bool) *IntArray {
 	if step == 0 {
 		panic(fmt.Sprintf(`invalid step value: %d`, step))
@@ -59,8 +59,8 @@ func NewIntArrayRange(start, end, step int, safe ...bool) *IntArray {
 	return NewIntArrayFrom(slice, safe...)
 }
 
-// NewIntArrayFrom creates and returns an array with given slice <array>.
-// The parameter <safe> is used to specify whether using array in concurrent-safety,
+// NewIntArrayFrom creates and returns an array with given slice `array`.
+// The parameter `safe` is used to specify whether using array in concurrent-safety,
 // which is false in default.
 func NewIntArrayFrom(array []int, safe ...bool) *IntArray {
 	return &IntArray{
@@ -69,8 +69,8 @@ func NewIntArrayFrom(array []int, safe ...bool) *IntArray {
 	}
 }
 
-// NewIntArrayFromCopy creates and returns an array from a copy of given slice <array>.
-// The parameter <safe> is used to specify whether using array in concurrent-safety,
+// NewIntArrayFromCopy creates and returns an array from a copy of given slice `array`.
+// The parameter `safe` is used to specify whether using array in concurrent-safety,
 // which is false in default.
 func NewIntArrayFromCopy(array []int, safe ...bool) *IntArray {
 	newArray := make([]int, len(array))
@@ -81,8 +81,15 @@ func NewIntArrayFromCopy(array []int, safe ...bool) *IntArray {
 	}
 }
 
+// At returns the value by the specified index.
+// If the given `index` is out of range of the array, it returns `0`.
+func (a *IntArray) At(index int) (value int) {
+	value, _ = a.Get(index)
+	return
+}
+
 // Get returns the value by the specified index.
-// If the given <index> is out of range of the array, the <found> is false.
+// If the given `index` is out of range of the array, the `found` is false.
 func (a *IntArray) Get(index int) (value int, found bool) {
 	a.mu.RLock()
 	defer a.mu.RUnlock()
@@ -103,7 +110,7 @@ func (a *IntArray) Set(index int, value int) error {
 	return nil
 }
 
-// SetArray sets the underlying slice array with the given <array>.
+// SetArray sets the underlying slice array with the given `array`.
 func (a *IntArray) SetArray(array []int) *IntArray {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -111,7 +118,7 @@ func (a *IntArray) SetArray(array []int) *IntArray {
 	return a
 }
 
-// Replace replaces the array items by given <array> from the beginning of array.
+// Replace replaces the array items by given `array` from the beginning of array.
 func (a *IntArray) Replace(array []int) *IntArray {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -136,7 +143,7 @@ func (a *IntArray) Sum() (sum int) {
 }
 
 // Sort sorts the array in increasing order.
-// The parameter <reverse> controls whether sort in increasing order(default) or decreasing order.
+// The parameter `reverse` controls whether sort in increasing order(default) or decreasing order.
 func (a *IntArray) Sort(reverse ...bool) *IntArray {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -153,7 +160,7 @@ func (a *IntArray) Sort(reverse ...bool) *IntArray {
 	return a
 }
 
-// SortFunc sorts the array by custom function <less>.
+// SortFunc sorts the array by custom function `less`.
 func (a *IntArray) SortFunc(less func(v1, v2 int) bool) *IntArray {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -163,7 +170,7 @@ func (a *IntArray) SortFunc(less func(v1, v2 int) bool) *IntArray {
 	return a
 }
 
-// InsertBefore inserts the <value> to the front of <index>.
+// InsertBefore inserts the `value` to the front of `index`.
 func (a *IntArray) InsertBefore(index int, value int) error {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -176,7 +183,7 @@ func (a *IntArray) InsertBefore(index int, value int) error {
 	return nil
 }
 
-// InsertAfter inserts the <value> to the back of <index>.
+// InsertAfter inserts the `value` to the back of `index`.
 func (a *IntArray) InsertAfter(index int, value int) error {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -190,7 +197,7 @@ func (a *IntArray) InsertAfter(index int, value int) error {
 }
 
 // Remove removes an item by index.
-// If the given <index> is out of range of the array, the <found> is false.
+// If the given `index` is out of range of the array, the `found` is false.
 func (a *IntArray) Remove(index int) (value int, found bool) {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -248,7 +255,7 @@ func (a *IntArray) PushRight(value ...int) *IntArray {
 }
 
 // PopLeft pops and returns an item from the beginning of array.
-// Note that if the array is empty, the <found> is false.
+// Note that if the array is empty, the `found` is false.
 func (a *IntArray) PopLeft() (value int, found bool) {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -261,7 +268,7 @@ func (a *IntArray) PopLeft() (value int, found bool) {
 }
 
 // PopRight pops and returns an item from the end of array.
-// Note that if the array is empty, the <found> is false.
+// Note that if the array is empty, the `found` is false.
 func (a *IntArray) PopRight() (value int, found bool) {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -275,16 +282,16 @@ func (a *IntArray) PopRight() (value int, found bool) {
 }
 
 // PopRand randomly pops and return an item out of array.
-// Note that if the array is empty, the <found> is false.
+// Note that if the array is empty, the `found` is false.
 func (a *IntArray) PopRand() (value int, found bool) {
 	a.mu.Lock()
 	defer a.mu.Unlock()
 	return a.doRemoveWithoutLock(grand.Intn(len(a.array)))
 }
 
-// PopRands randomly pops and returns <size> items out of array.
-// If the given <size> is greater than size of the array, it returns all elements of the array.
-// Note that if given <size> <= 0 or the array is empty, it returns nil.
+// PopRands randomly pops and returns `size` items out of array.
+// If the given `size` is greater than size of the array, it returns all elements of the array.
+// Note that if given `size` <= 0 or the array is empty, it returns nil.
 func (a *IntArray) PopRands(size int) []int {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -301,9 +308,9 @@ func (a *IntArray) PopRands(size int) []int {
 	return array
 }
 
-// PopLefts pops and returns <size> items from the beginning of array.
-// If the given <size> is greater than size of the array, it returns all elements of the array.
-// Note that if given <size> <= 0 or the array is empty, it returns nil.
+// PopLefts pops and returns `size` items from the beginning of array.
+// If the given `size` is greater than size of the array, it returns all elements of the array.
+// Note that if given `size` <= 0 or the array is empty, it returns nil.
 func (a *IntArray) PopLefts(size int) []int {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -320,9 +327,9 @@ func (a *IntArray) PopLefts(size int) []int {
 	return value
 }
 
-// PopRights pops and returns <size> items from the end of array.
-// If the given <size> is greater than size of the array, it returns all elements of the array.
-// Note that if given <size> <= 0 or the array is empty, it returns nil.
+// PopRights pops and returns `size` items from the end of array.
+// If the given `size` is greater than size of the array, it returns all elements of the array.
+// Note that if given `size` <= 0 or the array is empty, it returns nil.
 func (a *IntArray) PopRights(size int) []int {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -344,8 +351,8 @@ func (a *IntArray) PopRights(size int) []int {
 // Notice, if in concurrent-safe usage, it returns a copy of slice;
 // else a pointer to the underlying data.
 //
-// If <end> is negative, then the offset will start from the end of array.
-// If <end> is omitted, then the sequence will have everything from start up
+// If `end` is negative, then the offset will start from the end of array.
+// If `end` is omitted, then the sequence will have everything from start up
 // until the end of the array.
 func (a *IntArray) Range(start int, end ...int) []int {
 	a.mu.RLock()
@@ -371,7 +378,7 @@ func (a *IntArray) Range(start int, end ...int) []int {
 }
 
 // SubSlice returns a slice of elements from the array as specified
-// by the <offset> and <size> parameters.
+// by the `offset` and `size` parameters.
 // If in concurrent safe usage, it returns a copy of the slice; else a pointer.
 //
 // If offset is non-negative, the sequence will start at that offset in the array.
@@ -487,7 +494,7 @@ func (a *IntArray) Contains(value int) bool {
 	return a.Search(value) != -1
 }
 
-// Search searches array by <value>, returns the index of <value>,
+// Search searches array by `value`, returns the index of `value`,
 // or returns -1 if not exists.
 func (a *IntArray) Search(value int) int {
 	a.mu.RLock()
@@ -522,7 +529,7 @@ func (a *IntArray) Unique() *IntArray {
 	return a
 }
 
-// LockFunc locks writing by callback function <f>.
+// LockFunc locks writing by callback function `f`.
 func (a *IntArray) LockFunc(f func(array []int)) *IntArray {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -530,7 +537,7 @@ func (a *IntArray) LockFunc(f func(array []int)) *IntArray {
 	return a
 }
 
-// RLockFunc locks reading by callback function <f>.
+// RLockFunc locks reading by callback function `f`.
 func (a *IntArray) RLockFunc(f func(array []int)) *IntArray {
 	a.mu.RLock()
 	defer a.mu.RUnlock()
@@ -538,16 +545,16 @@ func (a *IntArray) RLockFunc(f func(array []int)) *IntArray {
 	return a
 }
 
-// Merge merges <array> into current array.
-// The parameter <array> can be any garray or slice type.
+// Merge merges `array` into current array.
+// The parameter `array` can be any garray or slice type.
 // The difference between Merge and Append is Append supports only specified slice type,
 // but Merge supports more parameter types.
 func (a *IntArray) Merge(array interface{}) *IntArray {
 	return a.Append(gconv.Ints(array)...)
 }
 
-// Fill fills an array with num entries of the value <value>,
-// keys starting at the <startIndex> parameter.
+// Fill fills an array with num entries of the value `value`,
+// keys starting at the `startIndex` parameter.
 func (a *IntArray) Fill(startIndex int, num int, value int) error {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -565,7 +572,7 @@ func (a *IntArray) Fill(startIndex int, num int, value int) error {
 }
 
 // Chunk splits an array into multiple arrays,
-// the size of each array is determined by <size>.
+// the size of each array is determined by `size`.
 // The last chunk may contain less than size elements.
 func (a *IntArray) Chunk(size int) [][]int {
 	if size < 1 {
@@ -587,9 +594,9 @@ func (a *IntArray) Chunk(size int) [][]int {
 	return n
 }
 
-// Pad pads array to the specified length with <value>.
+// Pad pads array to the specified length with `value`.
 // If size is positive then the array is padded on the right, or negative on the left.
-// If the absolute value of <size> is less than or equal to the length of the array
+// If the absolute value of `size` is less than or equal to the length of the array
 // then no padding takes place.
 func (a *IntArray) Pad(size int, value int) *IntArray {
 	a.mu.Lock()
@@ -624,7 +631,7 @@ func (a *IntArray) Rand() (value int, found bool) {
 	return a.array[grand.Intn(len(a.array))], true
 }
 
-// Rands randomly returns <size> items from array(no deleting).
+// Rands randomly returns `size` items from array(no deleting).
 func (a *IntArray) Rands(size int) []int {
 	a.mu.RLock()
 	defer a.mu.RUnlock()
@@ -658,7 +665,7 @@ func (a *IntArray) Reverse() *IntArray {
 	return a
 }
 
-// Join joins array elements with a string <glue>.
+// Join joins array elements with a string `glue`.
 func (a *IntArray) Join(glue string) string {
 	a.mu.RLock()
 	defer a.mu.RUnlock()
@@ -691,8 +698,8 @@ func (a *IntArray) Iterator(f func(k int, v int) bool) {
 	a.IteratorAsc(f)
 }
 
-// IteratorAsc iterates the array readonly in ascending order with given callback function <f>.
-// If <f> returns true, then it continues iterating; or false to stop.
+// IteratorAsc iterates the array readonly in ascending order with given callback function `f`.
+// If `f` returns true, then it continues iterating; or false to stop.
 func (a *IntArray) IteratorAsc(f func(k int, v int) bool) {
 	a.mu.RLock()
 	defer a.mu.RUnlock()
@@ -703,8 +710,8 @@ func (a *IntArray) IteratorAsc(f func(k int, v int) bool) {
 	}
 }
 
-// IteratorDesc iterates the array readonly in descending order with given callback function <f>.
-// If <f> returns true, then it continues iterating; or false to stop.
+// IteratorDesc iterates the array readonly in descending order with given callback function `f`.
+// If `f` returns true, then it continues iterating; or false to stop.
 func (a *IntArray) IteratorDesc(f func(k int, v int) bool) {
 	a.mu.RLock()
 	defer a.mu.RUnlock()
@@ -768,7 +775,7 @@ func (a *IntArray) FilterEmpty() *IntArray {
 	return a
 }
 
-// Walk applies a user supplied function <f> to every item of array.
+// Walk applies a user supplied function `f` to every item of array.
 func (a *IntArray) Walk(f func(value int) int) *IntArray {
 	a.mu.Lock()
 	defer a.mu.Unlock()
diff --git a/container/garray/garray_normal_str.go b/container/garray/garray_normal_str.go
index 523a75123..f1754e80d 100644
--- a/container/garray/garray_normal_str.go
+++ b/container/garray/garray_normal_str.go
@@ -30,14 +30,14 @@ type StrArray struct {
 }
 
 // NewStrArray creates and returns an empty array.
-// The parameter <safe> is used to specify whether using array in concurrent-safety,
+// The parameter `safe` is used to specify whether using array in concurrent-safety,
 // which is false in default.
 func NewStrArray(safe ...bool) *StrArray {
 	return NewStrArraySize(0, 0, safe...)
 }
 
 // NewStrArraySize create and returns an array with given size and cap.
-// The parameter <safe> is used to specify whether using array in concurrent-safety,
+// The parameter `safe` is used to specify whether using array in concurrent-safety,
 // which is false in default.
 func NewStrArraySize(size int, cap int, safe ...bool) *StrArray {
 	return &StrArray{
@@ -46,8 +46,8 @@ func NewStrArraySize(size int, cap int, safe ...bool) *StrArray {
 	}
 }
 
-// NewStrArrayFrom creates and returns an array with given slice <array>.
-// The parameter <safe> is used to specify whether using array in concurrent-safety,
+// NewStrArrayFrom creates and returns an array with given slice `array`.
+// The parameter `safe` is used to specify whether using array in concurrent-safety,
 // which is false in default.
 func NewStrArrayFrom(array []string, safe ...bool) *StrArray {
 	return &StrArray{
@@ -56,8 +56,8 @@ func NewStrArrayFrom(array []string, safe ...bool) *StrArray {
 	}
 }
 
-// NewStrArrayFromCopy creates and returns an array from a copy of given slice <array>.
-// The parameter <safe> is used to specify whether using array in concurrent-safety,
+// NewStrArrayFromCopy creates and returns an array from a copy of given slice `array`.
+// The parameter `safe` is used to specify whether using array in concurrent-safety,
 // which is false in default.
 func NewStrArrayFromCopy(array []string, safe ...bool) *StrArray {
 	newArray := make([]string, len(array))
@@ -68,8 +68,15 @@ func NewStrArrayFromCopy(array []string, safe ...bool) *StrArray {
 	}
 }
 
+// At returns the value by the specified index.
+// If the given `index` is out of range of the array, it returns an empty string.
+func (a *StrArray) At(index int) (value string) {
+	value, _ = a.Get(index)
+	return
+}
+
 // Get returns the value by the specified index.
-// If the given <index> is out of range of the array, the <found> is false.
+// If the given `index` is out of range of the array, the `found` is false.
 func (a *StrArray) Get(index int) (value string, found bool) {
 	a.mu.RLock()
 	defer a.mu.RUnlock()
@@ -90,7 +97,7 @@ func (a *StrArray) Set(index int, value string) error {
 	return nil
 }
 
-// SetArray sets the underlying slice array with the given <array>.
+// SetArray sets the underlying slice array with the given `array`.
 func (a *StrArray) SetArray(array []string) *StrArray {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -98,7 +105,7 @@ func (a *StrArray) SetArray(array []string) *StrArray {
 	return a
 }
 
-// Replace replaces the array items by given <array> from the beginning of array.
+// Replace replaces the array items by given `array` from the beginning of array.
 func (a *StrArray) Replace(array []string) *StrArray {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -123,7 +130,7 @@ func (a *StrArray) Sum() (sum int) {
 }
 
 // Sort sorts the array in increasing order.
-// The parameter <reverse> controls whether sort
+// The parameter `reverse` controls whether sort
 // in increasing order(default) or decreasing order
 func (a *StrArray) Sort(reverse ...bool) *StrArray {
 	a.mu.Lock()
@@ -141,7 +148,7 @@ func (a *StrArray) Sort(reverse ...bool) *StrArray {
 	return a
 }
 
-// SortFunc sorts the array by custom function <less>.
+// SortFunc sorts the array by custom function `less`.
 func (a *StrArray) SortFunc(less func(v1, v2 string) bool) *StrArray {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -151,7 +158,7 @@ func (a *StrArray) SortFunc(less func(v1, v2 string) bool) *StrArray {
 	return a
 }
 
-// InsertBefore inserts the <value> to the front of <index>.
+// InsertBefore inserts the `value` to the front of `index`.
 func (a *StrArray) InsertBefore(index int, value string) error {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -164,7 +171,7 @@ func (a *StrArray) InsertBefore(index int, value string) error {
 	return nil
 }
 
-// InsertAfter inserts the <value> to the back of <index>.
+// InsertAfter inserts the `value` to the back of `index`.
 func (a *StrArray) InsertAfter(index int, value string) error {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -178,7 +185,7 @@ func (a *StrArray) InsertAfter(index int, value string) error {
 }
 
 // Remove removes an item by index.
-// If the given <index> is out of range of the array, the <found> is false.
+// If the given `index` is out of range of the array, the `found` is false.
 func (a *StrArray) Remove(index int) (value string, found bool) {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -236,7 +243,7 @@ func (a *StrArray) PushRight(value ...string) *StrArray {
 }
 
 // PopLeft pops and returns an item from the beginning of array.
-// Note that if the array is empty, the <found> is false.
+// Note that if the array is empty, the `found` is false.
 func (a *StrArray) PopLeft() (value string, found bool) {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -249,7 +256,7 @@ func (a *StrArray) PopLeft() (value string, found bool) {
 }
 
 // PopRight pops and returns an item from the end of array.
-// Note that if the array is empty, the <found> is false.
+// Note that if the array is empty, the `found` is false.
 func (a *StrArray) PopRight() (value string, found bool) {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -263,16 +270,16 @@ func (a *StrArray) PopRight() (value string, found bool) {
 }
 
 // PopRand randomly pops and return an item out of array.
-// Note that if the array is empty, the <found> is false.
+// Note that if the array is empty, the `found` is false.
 func (a *StrArray) PopRand() (value string, found bool) {
 	a.mu.Lock()
 	defer a.mu.Unlock()
 	return a.doRemoveWithoutLock(grand.Intn(len(a.array)))
 }
 
-// PopRands randomly pops and returns <size> items out of array.
-// If the given <size> is greater than size of the array, it returns all elements of the array.
-// Note that if given <size> <= 0 or the array is empty, it returns nil.
+// PopRands randomly pops and returns `size` items out of array.
+// If the given `size` is greater than size of the array, it returns all elements of the array.
+// Note that if given `size` <= 0 or the array is empty, it returns nil.
 func (a *StrArray) PopRands(size int) []string {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -289,9 +296,9 @@ func (a *StrArray) PopRands(size int) []string {
 	return array
 }
 
-// PopLefts pops and returns <size> items from the beginning of array.
-// If the given <size> is greater than size of the array, it returns all elements of the array.
-// Note that if given <size> <= 0 or the array is empty, it returns nil.
+// PopLefts pops and returns `size` items from the beginning of array.
+// If the given `size` is greater than size of the array, it returns all elements of the array.
+// Note that if given `size` <= 0 or the array is empty, it returns nil.
 func (a *StrArray) PopLefts(size int) []string {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -308,9 +315,9 @@ func (a *StrArray) PopLefts(size int) []string {
 	return value
 }
 
-// PopRights pops and returns <size> items from the end of array.
-// If the given <size> is greater than size of the array, it returns all elements of the array.
-// Note that if given <size> <= 0 or the array is empty, it returns nil.
+// PopRights pops and returns `size` items from the end of array.
+// If the given `size` is greater than size of the array, it returns all elements of the array.
+// Note that if given `size` <= 0 or the array is empty, it returns nil.
 func (a *StrArray) PopRights(size int) []string {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -332,8 +339,8 @@ func (a *StrArray) PopRights(size int) []string {
 // Notice, if in concurrent-safe usage, it returns a copy of slice;
 // else a pointer to the underlying data.
 //
-// If <end> is negative, then the offset will start from the end of array.
-// If <end> is omitted, then the sequence will have everything from start up
+// If `end` is negative, then the offset will start from the end of array.
+// If `end` is omitted, then the sequence will have everything from start up
 // until the end of the array.
 func (a *StrArray) Range(start int, end ...int) []string {
 	a.mu.RLock()
@@ -359,7 +366,7 @@ func (a *StrArray) Range(start int, end ...int) []string {
 }
 
 // SubSlice returns a slice of elements from the array as specified
-// by the <offset> and <size> parameters.
+// by the `offset` and `size` parameters.
 // If in concurrent safe usage, it returns a copy of the slice; else a pointer.
 //
 // If offset is non-negative, the sequence will start at that offset in the array.
@@ -491,7 +498,7 @@ func (a *StrArray) ContainsI(value string) bool {
 	return false
 }
 
-// Search searches array by <value>, returns the index of <value>,
+// Search searches array by `value`, returns the index of `value`,
 // or returns -1 if not exists.
 func (a *StrArray) Search(value string) int {
 	a.mu.RLock()
@@ -526,7 +533,7 @@ func (a *StrArray) Unique() *StrArray {
 	return a
 }
 
-// LockFunc locks writing by callback function <f>.
+// LockFunc locks writing by callback function `f`.
 func (a *StrArray) LockFunc(f func(array []string)) *StrArray {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -534,7 +541,7 @@ func (a *StrArray) LockFunc(f func(array []string)) *StrArray {
 	return a
 }
 
-// RLockFunc locks reading by callback function <f>.
+// RLockFunc locks reading by callback function `f`.
 func (a *StrArray) RLockFunc(f func(array []string)) *StrArray {
 	a.mu.RLock()
 	defer a.mu.RUnlock()
@@ -542,16 +549,16 @@ func (a *StrArray) RLockFunc(f func(array []string)) *StrArray {
 	return a
 }
 
-// Merge merges <array> into current array.
-// The parameter <array> can be any garray or slice type.
+// Merge merges `array` into current array.
+// The parameter `array` can be any garray or slice type.
 // The difference between Merge and Append is Append supports only specified slice type,
 // but Merge supports more parameter types.
 func (a *StrArray) Merge(array interface{}) *StrArray {
 	return a.Append(gconv.Strings(array)...)
 }
 
-// Fill fills an array with num entries of the value <value>,
-// keys starting at the <startIndex> parameter.
+// Fill fills an array with num entries of the value `value`,
+// keys starting at the `startIndex` parameter.
 func (a *StrArray) Fill(startIndex int, num int, value string) error {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -569,7 +576,7 @@ func (a *StrArray) Fill(startIndex int, num int, value string) error {
 }
 
 // Chunk splits an array into multiple arrays,
-// the size of each array is determined by <size>.
+// the size of each array is determined by `size`.
 // The last chunk may contain less than size elements.
 func (a *StrArray) Chunk(size int) [][]string {
 	if size < 1 {
@@ -591,9 +598,9 @@ func (a *StrArray) Chunk(size int) [][]string {
 	return n
 }
 
-// Pad pads array to the specified length with <value>.
+// Pad pads array to the specified length with `value`.
 // If size is positive then the array is padded on the right, or negative on the left.
-// If the absolute value of <size> is less than or equal to the length of the array
+// If the absolute value of `size` is less than or equal to the length of the array
 // then no padding takes place.
 func (a *StrArray) Pad(size int, value string) *StrArray {
 	a.mu.Lock()
@@ -628,7 +635,7 @@ func (a *StrArray) Rand() (value string, found bool) {
 	return a.array[grand.Intn(len(a.array))], true
 }
 
-// Rands randomly returns <size> items from array(no deleting).
+// Rands randomly returns `size` items from array(no deleting).
 func (a *StrArray) Rands(size int) []string {
 	a.mu.RLock()
 	defer a.mu.RUnlock()
@@ -662,7 +669,7 @@ func (a *StrArray) Reverse() *StrArray {
 	return a
 }
 
-// Join joins array elements with a string <glue>.
+// Join joins array elements with a string `glue`.
 func (a *StrArray) Join(glue string) string {
 	a.mu.RLock()
 	defer a.mu.RUnlock()
@@ -695,8 +702,8 @@ func (a *StrArray) Iterator(f func(k int, v string) bool) {
 	a.IteratorAsc(f)
 }
 
-// IteratorAsc iterates the array readonly in ascending order with given callback function <f>.
-// If <f> returns true, then it continues iterating; or false to stop.
+// IteratorAsc iterates the array readonly in ascending order with given callback function `f`.
+// If `f` returns true, then it continues iterating; or false to stop.
 func (a *StrArray) IteratorAsc(f func(k int, v string) bool) {
 	a.mu.RLock()
 	defer a.mu.RUnlock()
@@ -707,8 +714,8 @@ func (a *StrArray) IteratorAsc(f func(k int, v string) bool) {
 	}
 }
 
-// IteratorDesc iterates the array readonly in descending order with given callback function <f>.
-// If <f> returns true, then it continues iterating; or false to stop.
+// IteratorDesc iterates the array readonly in descending order with given callback function `f`.
+// If `f` returns true, then it continues iterating; or false to stop.
 func (a *StrArray) IteratorDesc(f func(k int, v string) bool) {
 	a.mu.RLock()
 	defer a.mu.RUnlock()
@@ -783,7 +790,7 @@ func (a *StrArray) FilterEmpty() *StrArray {
 	return a
 }
 
-// Walk applies a user supplied function <f> to every item of array.
+// Walk applies a user supplied function `f` to every item of array.
 func (a *StrArray) Walk(f func(value string) string) *StrArray {
 	a.mu.Lock()
 	defer a.mu.Unlock()
diff --git a/container/garray/garray_sorted_any.go b/container/garray/garray_sorted_any.go
index 91d7fa073..cd14d6252 100644
--- a/container/garray/garray_sorted_any.go
+++ b/container/garray/garray_sorted_any.go
@@ -34,8 +34,8 @@ type SortedArray struct {
 }
 
 // NewSortedArray creates and returns an empty sorted array.
-// The parameter <safe> is used to specify whether using array in concurrent-safety, which is false in default.
-// The parameter <comparator> used to compare values to sort in array,
+// The parameter `safe` is used to specify whether using array in concurrent-safety, which is false in default.
+// The parameter `comparator` used to compare values to sort in array,
 // if it returns value < 0, means v1 < v2; the v1 will be inserted before v2;
 // if it returns value = 0, means v1 = v2; the v1 will be replaced by v2;
 // if it returns value > 0, means v1 > v2; the v1 will be inserted after v2;
@@ -44,7 +44,7 @@ func NewSortedArray(comparator func(a, b interface{}) int, safe ...bool) *Sorted
 }
 
 // NewSortedArraySize create and returns an sorted array with given size and cap.
-// The parameter <safe> is used to specify whether using array in concurrent-safety,
+// The parameter `safe` is used to specify whether using array in concurrent-safety,
 // which is false in default.
 func NewSortedArraySize(cap int, comparator func(a, b interface{}) int, safe ...bool) *SortedArray {
 	return &SortedArray{
@@ -54,8 +54,8 @@ func NewSortedArraySize(cap int, comparator func(a, b interface{}) int, safe ...
 	}
 }
 
-// NewSortedArrayRange creates and returns a array by a range from <start> to <end>
-// with step value <step>.
+// NewSortedArrayRange creates and returns a array by a range from `start` to `end`
+// with step value `step`.
 func NewSortedArrayRange(start, end, step int, comparator func(a, b interface{}) int, safe ...bool) *SortedArray {
 	if step == 0 {
 		panic(fmt.Sprintf(`invalid step value: %d`, step))
@@ -69,8 +69,8 @@ func NewSortedArrayRange(start, end, step int, comparator func(a, b interface{})
 	return NewSortedArrayFrom(slice, comparator, safe...)
 }
 
-// NewSortedArrayFrom creates and returns an sorted array with given slice <array>.
-// The parameter <safe> is used to specify whether using array in concurrent-safety,
+// NewSortedArrayFrom creates and returns an sorted array with given slice `array`.
+// The parameter `safe` is used to specify whether using array in concurrent-safety,
 // which is false in default.
 func NewSortedArrayFrom(array []interface{}, comparator func(a, b interface{}) int, safe ...bool) *SortedArray {
 	a := NewSortedArraySize(0, comparator, safe...)
@@ -81,8 +81,8 @@ func NewSortedArrayFrom(array []interface{}, comparator func(a, b interface{}) i
 	return a
 }
 
-// NewSortedArrayFromCopy creates and returns an sorted array from a copy of given slice <array>.
-// The parameter <safe> is used to specify whether using array in concurrent-safety,
+// NewSortedArrayFromCopy creates and returns an sorted array from a copy of given slice `array`.
+// The parameter `safe` is used to specify whether using array in concurrent-safety,
 // which is false in default.
 func NewSortedArrayFromCopy(array []interface{}, comparator func(a, b interface{}) int, safe ...bool) *SortedArray {
 	newArray := make([]interface{}, len(array))
@@ -90,7 +90,14 @@ func NewSortedArrayFromCopy(array []interface{}, comparator func(a, b interface{
 	return NewSortedArrayFrom(newArray, comparator, safe...)
 }
 
-// SetArray sets the underlying slice array with the given <array>.
+// At returns the value by the specified index.
+// If the given `index` is out of range of the array, it returns `nil`.
+func (a *SortedArray) At(index int) (value interface{}) {
+	value, _ = a.Get(index)
+	return
+}
+
+// SetArray sets the underlying slice array with the given `array`.
 func (a *SortedArray) SetArray(array []interface{}) *SortedArray {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -113,7 +120,7 @@ func (a *SortedArray) SetComparator(comparator func(a, b interface{}) int) {
 }
 
 // Sort sorts the array in increasing order.
-// The parameter <reverse> controls whether sort
+// The parameter `reverse` controls whether sort
 // in increasing order(default) or decreasing order
 func (a *SortedArray) Sort() *SortedArray {
 	a.mu.Lock()
@@ -157,7 +164,7 @@ func (a *SortedArray) Append(values ...interface{}) *SortedArray {
 }
 
 // Get returns the value by the specified index.
-// If the given <index> is out of range of the array, the <found> is false.
+// If the given `index` is out of range of the array, the `found` is false.
 func (a *SortedArray) Get(index int) (value interface{}, found bool) {
 	a.mu.RLock()
 	defer a.mu.RUnlock()
@@ -168,7 +175,7 @@ func (a *SortedArray) Get(index int) (value interface{}, found bool) {
 }
 
 // Remove removes an item by index.
-// If the given <index> is out of range of the array, the <found> is false.
+// If the given `index` is out of range of the array, the `found` is false.
 func (a *SortedArray) Remove(index int) (value interface{}, found bool) {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -209,7 +216,7 @@ func (a *SortedArray) RemoveValue(value interface{}) bool {
 }
 
 // PopLeft pops and returns an item from the beginning of array.
-// Note that if the array is empty, the <found> is false.
+// Note that if the array is empty, the `found` is false.
 func (a *SortedArray) PopLeft() (value interface{}, found bool) {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -222,7 +229,7 @@ func (a *SortedArray) PopLeft() (value interface{}, found bool) {
 }
 
 // PopRight pops and returns an item from the end of array.
-// Note that if the array is empty, the <found> is false.
+// Note that if the array is empty, the `found` is false.
 func (a *SortedArray) PopRight() (value interface{}, found bool) {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -236,14 +243,14 @@ func (a *SortedArray) PopRight() (value interface{}, found bool) {
 }
 
 // PopRand randomly pops and return an item out of array.
-// Note that if the array is empty, the <found> is false.
+// Note that if the array is empty, the `found` is false.
 func (a *SortedArray) PopRand() (value interface{}, found bool) {
 	a.mu.Lock()
 	defer a.mu.Unlock()
 	return a.doRemoveWithoutLock(grand.Intn(len(a.array)))
 }
 
-// PopRands randomly pops and returns <size> items out of array.
+// PopRands randomly pops and returns `size` items out of array.
 func (a *SortedArray) PopRands(size int) []interface{} {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -260,7 +267,7 @@ func (a *SortedArray) PopRands(size int) []interface{} {
 	return array
 }
 
-// PopLefts pops and returns <size> items from the beginning of array.
+// PopLefts pops and returns `size` items from the beginning of array.
 func (a *SortedArray) PopLefts(size int) []interface{} {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -277,7 +284,7 @@ func (a *SortedArray) PopLefts(size int) []interface{} {
 	return value
 }
 
-// PopRights pops and returns <size> items from the end of array.
+// PopRights pops and returns `size` items from the end of array.
 func (a *SortedArray) PopRights(size int) []interface{} {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -299,8 +306,8 @@ func (a *SortedArray) PopRights(size int) []interface{} {
 // Notice, if in concurrent-safe usage, it returns a copy of slice;
 // else a pointer to the underlying data.
 //
-// If <end> is negative, then the offset will start from the end of array.
-// If <end> is omitted, then the sequence will have everything from start up
+// If `end` is negative, then the offset will start from the end of array.
+// If `end` is omitted, then the sequence will have everything from start up
 // until the end of the array.
 func (a *SortedArray) Range(start int, end ...int) []interface{} {
 	a.mu.RLock()
@@ -326,7 +333,7 @@ func (a *SortedArray) Range(start int, end ...int) []interface{} {
 }
 
 // SubSlice returns a slice of elements from the array as specified
-// by the <offset> and <size> parameters.
+// by the `offset` and `size` parameters.
 // If in concurrent safe usage, it returns a copy of the slice; else a pointer.
 //
 // If offset is non-negative, the sequence will start at that offset in the array.
@@ -419,7 +426,7 @@ func (a *SortedArray) Contains(value interface{}) bool {
 	return a.Search(value) != -1
 }
 
-// Search searches array by <value>, returns the index of <value>,
+// Search searches array by `value`, returns the index of `value`,
 // or returns -1 if not exists.
 func (a *SortedArray) Search(value interface{}) (index int) {
 	if i, r := a.binSearch(value, true); r == 0 {
@@ -430,9 +437,9 @@ func (a *SortedArray) Search(value interface{}) (index int) {
 
 // Binary search.
 // It returns the last compared index and the result.
-// If <result> equals to 0, it means the value at <index> is equals to <value>.
-// If <result> lesser than 0, it means the value at <index> is lesser than <value>.
-// If <result> greater than 0, it means the value at <index> is greater than <value>.
+// If `result` equals to 0, it means the value at `index` is equals to `value`.
+// If `result` lesser than 0, it means the value at `index` is lesser than `value`.
+// If `result` greater than 0, it means the value at `index` is greater than `value`.
 func (a *SortedArray) binSearch(value interface{}, lock bool) (index int, result int) {
 	if lock {
 		a.mu.RLock()
@@ -512,7 +519,7 @@ func (a *SortedArray) Clear() *SortedArray {
 	return a
 }
 
-// LockFunc locks writing by callback function <f>.
+// LockFunc locks writing by callback function `f`.
 func (a *SortedArray) LockFunc(f func(array []interface{})) *SortedArray {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -526,7 +533,7 @@ func (a *SortedArray) LockFunc(f func(array []interface{})) *SortedArray {
 	return a
 }
 
-// RLockFunc locks reading by callback function <f>.
+// RLockFunc locks reading by callback function `f`.
 func (a *SortedArray) RLockFunc(f func(array []interface{})) *SortedArray {
 	a.mu.RLock()
 	defer a.mu.RUnlock()
@@ -534,8 +541,8 @@ func (a *SortedArray) RLockFunc(f func(array []interface{})) *SortedArray {
 	return a
 }
 
-// Merge merges <array> into current array.
-// The parameter <array> can be any garray or slice type.
+// Merge merges `array` into current array.
+// The parameter `array` can be any garray or slice type.
 // The difference between Merge and Append is Append supports only specified slice type,
 // but Merge supports more parameter types.
 func (a *SortedArray) Merge(array interface{}) *SortedArray {
@@ -543,7 +550,7 @@ func (a *SortedArray) Merge(array interface{}) *SortedArray {
 }
 
 // Chunk splits an array into multiple arrays,
-// the size of each array is determined by <size>.
+// the size of each array is determined by `size`.
 // The last chunk may contain less than size elements.
 func (a *SortedArray) Chunk(size int) [][]interface{} {
 	if size < 1 {
@@ -575,7 +582,7 @@ func (a *SortedArray) Rand() (value interface{}, found bool) {
 	return a.array[grand.Intn(len(a.array))], true
 }
 
-// Rands randomly returns <size> items from array(no deleting).
+// Rands randomly returns `size` items from array(no deleting).
 func (a *SortedArray) Rands(size int) []interface{} {
 	a.mu.RLock()
 	defer a.mu.RUnlock()
@@ -589,7 +596,7 @@ func (a *SortedArray) Rands(size int) []interface{} {
 	return array
 }
 
-// Join joins array elements with a string <glue>.
+// Join joins array elements with a string `glue`.
 func (a *SortedArray) Join(glue string) string {
 	a.mu.RLock()
 	defer a.mu.RUnlock()
@@ -622,8 +629,8 @@ func (a *SortedArray) Iterator(f func(k int, v interface{}) bool) {
 	a.IteratorAsc(f)
 }
 
-// IteratorAsc iterates the array readonly in ascending order with given callback function <f>.
-// If <f> returns true, then it continues iterating; or false to stop.
+// IteratorAsc iterates the array readonly in ascending order with given callback function `f`.
+// If `f` returns true, then it continues iterating; or false to stop.
 func (a *SortedArray) IteratorAsc(f func(k int, v interface{}) bool) {
 	a.mu.RLock()
 	defer a.mu.RUnlock()
@@ -634,8 +641,8 @@ func (a *SortedArray) IteratorAsc(f func(k int, v interface{}) bool) {
 	}
 }
 
-// IteratorDesc iterates the array readonly in descending order with given callback function <f>.
-// If <f> returns true, then it continues iterating; or false to stop.
+// IteratorDesc iterates the array readonly in descending order with given callback function `f`.
+// If `f` returns true, then it continues iterating; or false to stop.
 func (a *SortedArray) IteratorDesc(f func(k int, v interface{}) bool) {
 	a.mu.RLock()
 	defer a.mu.RUnlock()
@@ -761,7 +768,7 @@ func (a *SortedArray) FilterEmpty() *SortedArray {
 	return a
 }
 
-// Walk applies a user supplied function <f> to every item of array.
+// Walk applies a user supplied function `f` to every item of array.
 func (a *SortedArray) Walk(f func(value interface{}) interface{}) *SortedArray {
 	a.mu.Lock()
 	defer a.mu.Unlock()
diff --git a/container/garray/garray_sorted_int.go b/container/garray/garray_sorted_int.go
index 6b96b2c3a..f250d989c 100644
--- a/container/garray/garray_sorted_int.go
+++ b/container/garray/garray_sorted_int.go
@@ -31,14 +31,14 @@ type SortedIntArray struct {
 }
 
 // NewSortedIntArray creates and returns an empty sorted array.
-// The parameter <safe> is used to specify whether using array in concurrent-safety,
+// The parameter `safe` is used to specify whether using array in concurrent-safety,
 // which is false in default.
 func NewSortedIntArray(safe ...bool) *SortedIntArray {
 	return NewSortedIntArraySize(0, safe...)
 }
 
 // NewSortedIntArrayComparator creates and returns an empty sorted array with specified comparator.
-// The parameter <safe> is used to specify whether using array in concurrent-safety which is false in default.
+// The parameter `safe` is used to specify whether using array in concurrent-safety which is false in default.
 func NewSortedIntArrayComparator(comparator func(a, b int) int, safe ...bool) *SortedIntArray {
 	array := NewSortedIntArray(safe...)
 	array.comparator = comparator
@@ -46,7 +46,7 @@ func NewSortedIntArrayComparator(comparator func(a, b int) int, safe ...bool) *S
 }
 
 // NewSortedIntArraySize create and returns an sorted array with given size and cap.
-// The parameter <safe> is used to specify whether using array in concurrent-safety,
+// The parameter `safe` is used to specify whether using array in concurrent-safety,
 // which is false in default.
 func NewSortedIntArraySize(cap int, safe ...bool) *SortedIntArray {
 	return &SortedIntArray{
@@ -56,8 +56,8 @@ func NewSortedIntArraySize(cap int, safe ...bool) *SortedIntArray {
 	}
 }
 
-// NewSortedIntArrayRange creates and returns a array by a range from <start> to <end>
-// with step value <step>.
+// NewSortedIntArrayRange creates and returns a array by a range from `start` to `end`
+// with step value `step`.
 func NewSortedIntArrayRange(start, end, step int, safe ...bool) *SortedIntArray {
 	if step == 0 {
 		panic(fmt.Sprintf(`invalid step value: %d`, step))
@@ -71,8 +71,8 @@ func NewSortedIntArrayRange(start, end, step int, safe ...bool) *SortedIntArray
 	return NewSortedIntArrayFrom(slice, safe...)
 }
 
-// NewIntArrayFrom creates and returns an sorted array with given slice <array>.
-// The parameter <safe> is used to specify whether using array in concurrent-safety,
+// NewSortedIntArrayFrom creates and returns an sorted array with given slice `array`.
+// The parameter `safe` is used to specify whether using array in concurrent-safety,
 // which is false in default.
 func NewSortedIntArrayFrom(array []int, safe ...bool) *SortedIntArray {
 	a := NewSortedIntArraySize(0, safe...)
@@ -81,8 +81,8 @@ func NewSortedIntArrayFrom(array []int, safe ...bool) *SortedIntArray {
 	return a
 }
 
-// NewSortedIntArrayFromCopy creates and returns an sorted array from a copy of given slice <array>.
-// The parameter <safe> is used to specify whether using array in concurrent-safety,
+// NewSortedIntArrayFromCopy creates and returns an sorted array from a copy of given slice `array`.
+// The parameter `safe` is used to specify whether using array in concurrent-safety,
 // which is false in default.
 func NewSortedIntArrayFromCopy(array []int, safe ...bool) *SortedIntArray {
 	newArray := make([]int, len(array))
@@ -90,7 +90,14 @@ func NewSortedIntArrayFromCopy(array []int, safe ...bool) *SortedIntArray {
 	return NewSortedIntArrayFrom(newArray, safe...)
 }
 
-// SetArray sets the underlying slice array with the given <array>.
+// At returns the value by the specified index.
+// If the given `index` is out of range of the array, it returns `0`.
+func (a *SortedIntArray) At(index int) (value int) {
+	value, _ = a.Get(index)
+	return
+}
+
+// SetArray sets the underlying slice array with the given `array`.
 func (a *SortedIntArray) SetArray(array []int) *SortedIntArray {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -100,7 +107,7 @@ func (a *SortedIntArray) SetArray(array []int) *SortedIntArray {
 }
 
 // Sort sorts the array in increasing order.
-// The parameter <reverse> controls whether sort
+// The parameter `reverse` controls whether sort
 // in increasing order(default) or decreasing order.
 func (a *SortedIntArray) Sort() *SortedIntArray {
 	a.mu.Lock()
@@ -142,7 +149,7 @@ func (a *SortedIntArray) Append(values ...int) *SortedIntArray {
 }
 
 // Get returns the value by the specified index.
-// If the given <index> is out of range of the array, the <found> is false.
+// If the given `index` is out of range of the array, the `found` is false.
 func (a *SortedIntArray) Get(index int) (value int, found bool) {
 	a.mu.RLock()
 	defer a.mu.RUnlock()
@@ -153,7 +160,7 @@ func (a *SortedIntArray) Get(index int) (value int, found bool) {
 }
 
 // Remove removes an item by index.
-// If the given <index> is out of range of the array, the <found> is false.
+// If the given `index` is out of range of the array, the `found` is false.
 func (a *SortedIntArray) Remove(index int) (value int, found bool) {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -194,7 +201,7 @@ func (a *SortedIntArray) RemoveValue(value int) bool {
 }
 
 // PopLeft pops and returns an item from the beginning of array.
-// Note that if the array is empty, the <found> is false.
+// Note that if the array is empty, the `found` is false.
 func (a *SortedIntArray) PopLeft() (value int, found bool) {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -207,7 +214,7 @@ func (a *SortedIntArray) PopLeft() (value int, found bool) {
 }
 
 // PopRight pops and returns an item from the end of array.
-// Note that if the array is empty, the <found> is false.
+// Note that if the array is empty, the `found` is false.
 func (a *SortedIntArray) PopRight() (value int, found bool) {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -221,16 +228,16 @@ func (a *SortedIntArray) PopRight() (value int, found bool) {
 }
 
 // PopRand randomly pops and return an item out of array.
-// Note that if the array is empty, the <found> is false.
+// Note that if the array is empty, the `found` is false.
 func (a *SortedIntArray) PopRand() (value int, found bool) {
 	a.mu.Lock()
 	defer a.mu.Unlock()
 	return a.doRemoveWithoutLock(grand.Intn(len(a.array)))
 }
 
-// PopRands randomly pops and returns <size> items out of array.
-// If the given <size> is greater than size of the array, it returns all elements of the array.
-// Note that if given <size> <= 0 or the array is empty, it returns nil.
+// PopRands randomly pops and returns `size` items out of array.
+// If the given `size` is greater than size of the array, it returns all elements of the array.
+// Note that if given `size` <= 0 or the array is empty, it returns nil.
 func (a *SortedIntArray) PopRands(size int) []int {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -247,9 +254,9 @@ func (a *SortedIntArray) PopRands(size int) []int {
 	return array
 }
 
-// PopLefts pops and returns <size> items from the beginning of array.
-// If the given <size> is greater than size of the array, it returns all elements of the array.
-// Note that if given <size> <= 0 or the array is empty, it returns nil.
+// PopLefts pops and returns `size` items from the beginning of array.
+// If the given `size` is greater than size of the array, it returns all elements of the array.
+// Note that if given `size` <= 0 or the array is empty, it returns nil.
 func (a *SortedIntArray) PopLefts(size int) []int {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -266,9 +273,9 @@ func (a *SortedIntArray) PopLefts(size int) []int {
 	return value
 }
 
-// PopRights pops and returns <size> items from the end of array.
-// If the given <size> is greater than size of the array, it returns all elements of the array.
-// Note that if given <size> <= 0 or the array is empty, it returns nil.
+// PopRights pops and returns `size` items from the end of array.
+// If the given `size` is greater than size of the array, it returns all elements of the array.
+// Note that if given `size` <= 0 or the array is empty, it returns nil.
 func (a *SortedIntArray) PopRights(size int) []int {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -290,8 +297,8 @@ func (a *SortedIntArray) PopRights(size int) []int {
 // Notice, if in concurrent-safe usage, it returns a copy of slice;
 // else a pointer to the underlying data.
 //
-// If <end> is negative, then the offset will start from the end of array.
-// If <end> is omitted, then the sequence will have everything from start up
+// If `end` is negative, then the offset will start from the end of array.
+// If `end` is omitted, then the sequence will have everything from start up
 // until the end of the array.
 func (a *SortedIntArray) Range(start int, end ...int) []int {
 	a.mu.RLock()
@@ -317,7 +324,7 @@ func (a *SortedIntArray) Range(start int, end ...int) []int {
 }
 
 // SubSlice returns a slice of elements from the array as specified
-// by the <offset> and <size> parameters.
+// by the `offset` and `size` parameters.
 // If in concurrent safe usage, it returns a copy of the slice; else a pointer.
 //
 // If offset is non-negative, the sequence will start at that offset in the array.
@@ -416,7 +423,7 @@ func (a *SortedIntArray) Contains(value int) bool {
 	return a.Search(value) != -1
 }
 
-// Search searches array by <value>, returns the index of <value>,
+// Search searches array by `value`, returns the index of `value`,
 // or returns -1 if not exists.
 func (a *SortedIntArray) Search(value int) (index int) {
 	if i, r := a.binSearch(value, true); r == 0 {
@@ -427,9 +434,9 @@ func (a *SortedIntArray) Search(value int) (index int) {
 
 // Binary search.
 // It returns the last compared index and the result.
-// If <result> equals to 0, it means the value at <index> is equals to <value>.
-// If <result> lesser than 0, it means the value at <index> is lesser than <value>.
-// If <result> greater than 0, it means the value at <index> is greater than <value>.
+// If `result` equals to 0, it means the value at `index` is equals to `value`.
+// If `result` lesser than 0, it means the value at `index` is lesser than `value`.
+// If `result` greater than 0, it means the value at `index` is greater than `value`.
 func (a *SortedIntArray) binSearch(value int, lock bool) (index int, result int) {
 	if lock {
 		a.mu.RLock()
@@ -509,7 +516,7 @@ func (a *SortedIntArray) Clear() *SortedIntArray {
 	return a
 }
 
-// LockFunc locks writing by callback function <f>.
+// LockFunc locks writing by callback function `f`.
 func (a *SortedIntArray) LockFunc(f func(array []int)) *SortedIntArray {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -517,7 +524,7 @@ func (a *SortedIntArray) LockFunc(f func(array []int)) *SortedIntArray {
 	return a
 }
 
-// RLockFunc locks reading by callback function <f>.
+// RLockFunc locks reading by callback function `f`.
 func (a *SortedIntArray) RLockFunc(f func(array []int)) *SortedIntArray {
 	a.mu.RLock()
 	defer a.mu.RUnlock()
@@ -525,8 +532,8 @@ func (a *SortedIntArray) RLockFunc(f func(array []int)) *SortedIntArray {
 	return a
 }
 
-// Merge merges <array> into current array.
-// The parameter <array> can be any garray or slice type.
+// Merge merges `array` into current array.
+// The parameter `array` can be any garray or slice type.
 // The difference between Merge and Append is Append supports only specified slice type,
 // but Merge supports more parameter types.
 func (a *SortedIntArray) Merge(array interface{}) *SortedIntArray {
@@ -534,7 +541,7 @@ func (a *SortedIntArray) Merge(array interface{}) *SortedIntArray {
 }
 
 // Chunk splits an array into multiple arrays,
-// the size of each array is determined by <size>.
+// the size of each array is determined by `size`.
 // The last chunk may contain less than size elements.
 func (a *SortedIntArray) Chunk(size int) [][]int {
 	if size < 1 {
@@ -566,7 +573,7 @@ func (a *SortedIntArray) Rand() (value int, found bool) {
 	return a.array[grand.Intn(len(a.array))], true
 }
 
-// Rands randomly returns <size> items from array(no deleting).
+// Rands randomly returns `size` items from array(no deleting).
 func (a *SortedIntArray) Rands(size int) []int {
 	a.mu.RLock()
 	defer a.mu.RUnlock()
@@ -580,7 +587,7 @@ func (a *SortedIntArray) Rands(size int) []int {
 	return array
 }
 
-// Join joins array elements with a string <glue>.
+// Join joins array elements with a string `glue`.
 func (a *SortedIntArray) Join(glue string) string {
 	a.mu.RLock()
 	defer a.mu.RUnlock()
@@ -613,8 +620,8 @@ func (a *SortedIntArray) Iterator(f func(k int, v int) bool) {
 	a.IteratorAsc(f)
 }
 
-// IteratorAsc iterates the array readonly in ascending order with given callback function <f>.
-// If <f> returns true, then it continues iterating; or false to stop.
+// IteratorAsc iterates the array readonly in ascending order with given callback function `f`.
+// If `f` returns true, then it continues iterating; or false to stop.
 func (a *SortedIntArray) IteratorAsc(f func(k int, v int) bool) {
 	a.mu.RLock()
 	defer a.mu.RUnlock()
@@ -625,8 +632,8 @@ func (a *SortedIntArray) IteratorAsc(f func(k int, v int) bool) {
 	}
 }
 
-// IteratorDesc iterates the array readonly in descending order with given callback function <f>.
-// If <f> returns true, then it continues iterating; or false to stop.
+// IteratorDesc iterates the array readonly in descending order with given callback function `f`.
+// If `f` returns true, then it continues iterating; or false to stop.
 func (a *SortedIntArray) IteratorDesc(f func(k int, v int) bool) {
 	a.mu.RLock()
 	defer a.mu.RUnlock()
@@ -707,7 +714,7 @@ func (a *SortedIntArray) FilterEmpty() *SortedIntArray {
 	return a
 }
 
-// Walk applies a user supplied function <f> to every item of array.
+// Walk applies a user supplied function `f` to every item of array.
 func (a *SortedIntArray) Walk(f func(value int) int) *SortedIntArray {
 	a.mu.Lock()
 	defer a.mu.Unlock()
diff --git a/container/garray/garray_sorted_str.go b/container/garray/garray_sorted_str.go
index 7b8e23b1b..896030e65 100644
--- a/container/garray/garray_sorted_str.go
+++ b/container/garray/garray_sorted_str.go
@@ -32,14 +32,14 @@ type SortedStrArray struct {
 }
 
 // NewSortedStrArray creates and returns an empty sorted array.
-// The parameter <safe> is used to specify whether using array in concurrent-safety,
+// The parameter `safe` is used to specify whether using array in concurrent-safety,
 // which is false in default.
 func NewSortedStrArray(safe ...bool) *SortedStrArray {
 	return NewSortedStrArraySize(0, safe...)
 }
 
 // NewSortedStrArrayComparator creates and returns an empty sorted array with specified comparator.
-// The parameter <safe> is used to specify whether using array in concurrent-safety which is false in default.
+// The parameter `safe` is used to specify whether using array in concurrent-safety which is false in default.
 func NewSortedStrArrayComparator(comparator func(a, b string) int, safe ...bool) *SortedStrArray {
 	array := NewSortedStrArray(safe...)
 	array.comparator = comparator
@@ -47,7 +47,7 @@ func NewSortedStrArrayComparator(comparator func(a, b string) int, safe ...bool)
 }
 
 // NewSortedStrArraySize create and returns an sorted array with given size and cap.
-// The parameter <safe> is used to specify whether using array in concurrent-safety,
+// The parameter `safe` is used to specify whether using array in concurrent-safety,
 // which is false in default.
 func NewSortedStrArraySize(cap int, safe ...bool) *SortedStrArray {
 	return &SortedStrArray{
@@ -57,8 +57,8 @@ func NewSortedStrArraySize(cap int, safe ...bool) *SortedStrArray {
 	}
 }
 
-// NewSortedStrArrayFrom creates and returns an sorted array with given slice <array>.
-// The parameter <safe> is used to specify whether using array in concurrent-safety,
+// NewSortedStrArrayFrom creates and returns an sorted array with given slice `array`.
+// The parameter `safe` is used to specify whether using array in concurrent-safety,
 // which is false in default.
 func NewSortedStrArrayFrom(array []string, safe ...bool) *SortedStrArray {
 	a := NewSortedStrArraySize(0, safe...)
@@ -67,8 +67,8 @@ func NewSortedStrArrayFrom(array []string, safe ...bool) *SortedStrArray {
 	return a
 }
 
-// NewSortedStrArrayFromCopy creates and returns an sorted array from a copy of given slice <array>.
-// The parameter <safe> is used to specify whether using array in concurrent-safety,
+// NewSortedStrArrayFromCopy creates and returns an sorted array from a copy of given slice `array`.
+// The parameter `safe` is used to specify whether using array in concurrent-safety,
 // which is false in default.
 func NewSortedStrArrayFromCopy(array []string, safe ...bool) *SortedStrArray {
 	newArray := make([]string, len(array))
@@ -76,7 +76,7 @@ func NewSortedStrArrayFromCopy(array []string, safe ...bool) *SortedStrArray {
 	return NewSortedStrArrayFrom(newArray, safe...)
 }
 
-// SetArray sets the underlying slice array with the given <array>.
+// SetArray sets the underlying slice array with the given `array`.
 func (a *SortedStrArray) SetArray(array []string) *SortedStrArray {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -85,8 +85,15 @@ func (a *SortedStrArray) SetArray(array []string) *SortedStrArray {
 	return a
 }
 
+// At returns the value by the specified index.
+// If the given `index` is out of range of the array, it returns an empty string.
+func (a *SortedStrArray) At(index int) (value string) {
+	value, _ = a.Get(index)
+	return
+}
+
 // Sort sorts the array in increasing order.
-// The parameter <reverse> controls whether sort
+// The parameter `reverse` controls whether sort
 // in increasing order(default) or decreasing order.
 func (a *SortedStrArray) Sort() *SortedStrArray {
 	a.mu.Lock()
@@ -128,7 +135,7 @@ func (a *SortedStrArray) Append(values ...string) *SortedStrArray {
 }
 
 // Get returns the value by the specified index.
-// If the given <index> is out of range of the array, the <found> is false.
+// If the given `index` is out of range of the array, the `found` is false.
 func (a *SortedStrArray) Get(index int) (value string, found bool) {
 	a.mu.RLock()
 	defer a.mu.RUnlock()
@@ -139,7 +146,7 @@ func (a *SortedStrArray) Get(index int) (value string, found bool) {
 }
 
 // Remove removes an item by index.
-// If the given <index> is out of range of the array, the <found> is false.
+// If the given `index` is out of range of the array, the `found` is false.
 func (a *SortedStrArray) Remove(index int) (value string, found bool) {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -180,7 +187,7 @@ func (a *SortedStrArray) RemoveValue(value string) bool {
 }
 
 // PopLeft pops and returns an item from the beginning of array.
-// Note that if the array is empty, the <found> is false.
+// Note that if the array is empty, the `found` is false.
 func (a *SortedStrArray) PopLeft() (value string, found bool) {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -193,7 +200,7 @@ func (a *SortedStrArray) PopLeft() (value string, found bool) {
 }
 
 // PopRight pops and returns an item from the end of array.
-// Note that if the array is empty, the <found> is false.
+// Note that if the array is empty, the `found` is false.
 func (a *SortedStrArray) PopRight() (value string, found bool) {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -207,16 +214,16 @@ func (a *SortedStrArray) PopRight() (value string, found bool) {
 }
 
 // PopRand randomly pops and return an item out of array.
-// Note that if the array is empty, the <found> is false.
+// Note that if the array is empty, the `found` is false.
 func (a *SortedStrArray) PopRand() (value string, found bool) {
 	a.mu.Lock()
 	defer a.mu.Unlock()
 	return a.doRemoveWithoutLock(grand.Intn(len(a.array)))
 }
 
-// PopRands randomly pops and returns <size> items out of array.
-// If the given <size> is greater than size of the array, it returns all elements of the array.
-// Note that if given <size> <= 0 or the array is empty, it returns nil.
+// PopRands randomly pops and returns `size` items out of array.
+// If the given `size` is greater than size of the array, it returns all elements of the array.
+// Note that if given `size` <= 0 or the array is empty, it returns nil.
 func (a *SortedStrArray) PopRands(size int) []string {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -233,9 +240,9 @@ func (a *SortedStrArray) PopRands(size int) []string {
 	return array
 }
 
-// PopLefts pops and returns <size> items from the beginning of array.
-// If the given <size> is greater than size of the array, it returns all elements of the array.
-// Note that if given <size> <= 0 or the array is empty, it returns nil.
+// PopLefts pops and returns `size` items from the beginning of array.
+// If the given `size` is greater than size of the array, it returns all elements of the array.
+// Note that if given `size` <= 0 or the array is empty, it returns nil.
 func (a *SortedStrArray) PopLefts(size int) []string {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -252,9 +259,9 @@ func (a *SortedStrArray) PopLefts(size int) []string {
 	return value
 }
 
-// PopRights pops and returns <size> items from the end of array.
-// If the given <size> is greater than size of the array, it returns all elements of the array.
-// Note that if given <size> <= 0 or the array is empty, it returns nil.
+// PopRights pops and returns `size` items from the end of array.
+// If the given `size` is greater than size of the array, it returns all elements of the array.
+// Note that if given `size` <= 0 or the array is empty, it returns nil.
 func (a *SortedStrArray) PopRights(size int) []string {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -276,8 +283,8 @@ func (a *SortedStrArray) PopRights(size int) []string {
 // Notice, if in concurrent-safe usage, it returns a copy of slice;
 // else a pointer to the underlying data.
 //
-// If <end> is negative, then the offset will start from the end of array.
-// If <end> is omitted, then the sequence will have everything from start up
+// If `end` is negative, then the offset will start from the end of array.
+// If `end` is omitted, then the sequence will have everything from start up
 // until the end of the array.
 func (a *SortedStrArray) Range(start int, end ...int) []string {
 	a.mu.RLock()
@@ -303,7 +310,7 @@ func (a *SortedStrArray) Range(start int, end ...int) []string {
 }
 
 // SubSlice returns a slice of elements from the array as specified
-// by the <offset> and <size> parameters.
+// by the `offset` and `size` parameters.
 // If in concurrent safe usage, it returns a copy of the slice; else a pointer.
 //
 // If offset is non-negative, the sequence will start at that offset in the array.
@@ -418,7 +425,7 @@ func (a *SortedStrArray) ContainsI(value string) bool {
 	return false
 }
 
-// Search searches array by <value>, returns the index of <value>,
+// Search searches array by `value`, returns the index of `value`,
 // or returns -1 if not exists.
 func (a *SortedStrArray) Search(value string) (index int) {
 	if i, r := a.binSearch(value, true); r == 0 {
@@ -429,9 +436,9 @@ func (a *SortedStrArray) Search(value string) (index int) {
 
 // Binary search.
 // It returns the last compared index and the result.
-// If <result> equals to 0, it means the value at <index> is equals to <value>.
-// If <result> lesser than 0, it means the value at <index> is lesser than <value>.
-// If <result> greater than 0, it means the value at <index> is greater than <value>.
+// If `result` equals to 0, it means the value at `index` is equals to `value`.
+// If `result` lesser than 0, it means the value at `index` is lesser than `value`.
+// If `result` greater than 0, it means the value at `index` is greater than `value`.
 func (a *SortedStrArray) binSearch(value string, lock bool) (index int, result int) {
 	if lock {
 		a.mu.RLock()
@@ -511,7 +518,7 @@ func (a *SortedStrArray) Clear() *SortedStrArray {
 	return a
 }
 
-// LockFunc locks writing by callback function <f>.
+// LockFunc locks writing by callback function `f`.
 func (a *SortedStrArray) LockFunc(f func(array []string)) *SortedStrArray {
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -519,7 +526,7 @@ func (a *SortedStrArray) LockFunc(f func(array []string)) *SortedStrArray {
 	return a
 }
 
-// RLockFunc locks reading by callback function <f>.
+// RLockFunc locks reading by callback function `f`.
 func (a *SortedStrArray) RLockFunc(f func(array []string)) *SortedStrArray {
 	a.mu.RLock()
 	defer a.mu.RUnlock()
@@ -527,8 +534,8 @@ func (a *SortedStrArray) RLockFunc(f func(array []string)) *SortedStrArray {
 	return a
 }
 
-// Merge merges <array> into current array.
-// The parameter <array> can be any garray or slice type.
+// Merge merges `array` into current array.
+// The parameter `array` can be any garray or slice type.
 // The difference between Merge and Append is Append supports only specified slice type,
 // but Merge supports more parameter types.
 func (a *SortedStrArray) Merge(array interface{}) *SortedStrArray {
@@ -536,7 +543,7 @@ func (a *SortedStrArray) Merge(array interface{}) *SortedStrArray {
 }
 
 // Chunk splits an array into multiple arrays,
-// the size of each array is determined by <size>.
+// the size of each array is determined by `size`.
 // The last chunk may contain less than size elements.
 func (a *SortedStrArray) Chunk(size int) [][]string {
 	if size < 1 {
@@ -568,7 +575,7 @@ func (a *SortedStrArray) Rand() (value string, found bool) {
 	return a.array[grand.Intn(len(a.array))], true
 }
 
-// Rands randomly returns <size> items from array(no deleting).
+// Rands randomly returns `size` items from array(no deleting).
 func (a *SortedStrArray) Rands(size int) []string {
 	a.mu.RLock()
 	defer a.mu.RUnlock()
@@ -582,7 +589,7 @@ func (a *SortedStrArray) Rands(size int) []string {
 	return array
 }
 
-// Join joins array elements with a string <glue>.
+// Join joins array elements with a string `glue`.
 func (a *SortedStrArray) Join(glue string) string {
 	a.mu.RLock()
 	defer a.mu.RUnlock()
@@ -615,8 +622,8 @@ func (a *SortedStrArray) Iterator(f func(k int, v string) bool) {
 	a.IteratorAsc(f)
 }
 
-// IteratorAsc iterates the array readonly in ascending order with given callback function <f>.
-// If <f> returns true, then it continues iterating; or false to stop.
+// IteratorAsc iterates the array readonly in ascending order with given callback function `f`.
+// If `f` returns true, then it continues iterating; or false to stop.
 func (a *SortedStrArray) IteratorAsc(f func(k int, v string) bool) {
 	a.mu.RLock()
 	defer a.mu.RUnlock()
@@ -627,8 +634,8 @@ func (a *SortedStrArray) IteratorAsc(f func(k int, v string) bool) {
 	}
 }
 
-// IteratorDesc iterates the array readonly in descending order with given callback function <f>.
-// If <f> returns true, then it continues iterating; or false to stop.
+// IteratorDesc iterates the array readonly in descending order with given callback function `f`.
+// If `f` returns true, then it continues iterating; or false to stop.
 func (a *SortedStrArray) IteratorDesc(f func(k int, v string) bool) {
 	a.mu.RLock()
 	defer a.mu.RUnlock()
@@ -720,7 +727,7 @@ func (a *SortedStrArray) FilterEmpty() *SortedStrArray {
 	return a
 }
 
-// Walk applies a user supplied function <f> to every item of array.
+// Walk applies a user supplied function `f` to every item of array.
 func (a *SortedStrArray) Walk(f func(value string) string) *SortedStrArray {
 	a.mu.Lock()
 	defer a.mu.Unlock()
diff --git a/container/garray/garray_z_example_any_test.go b/container/garray/garray_z_example_any_test.go
index f79fe1adc..fccf99716 100644
--- a/container/garray/garray_z_example_any_test.go
+++ b/container/garray/garray_z_example_any_test.go
@@ -75,14 +75,14 @@ func ExampleNew() {
 func ExampleArray_Iterator() {
 	array := garray.NewArrayFrom(g.Slice{"a", "b", "c"})
 	// Iterator is alias of IteratorAsc, which iterates the array readonly in ascending order
-	//  with given callback function <f>.
-	// If <f> returns true, then it continues iterating; or false to stop.
+	//  with given callback function `f`.
+	// If `f` returns true, then it continues iterating; or false to stop.
 	array.Iterator(func(k int, v interface{}) bool {
 		fmt.Println(k, v)
 		return true
 	})
-	// IteratorDesc iterates the array readonly in descending order with given callback function <f>.
-	// If <f> returns true, then it continues iterating; or false to stop.
+	// IteratorDesc iterates the array readonly in descending order with given callback function `f`.
+	// If `f` returns true, then it continues iterating; or false to stop.
 	array.IteratorDesc(func(k int, v interface{}) bool {
 		fmt.Println(k, v)
 		return true
@@ -150,7 +150,7 @@ func ExampleArray_Chunk() {
 	array := garray.NewFrom(g.Slice{1, 2, 3, 4, 5, 6, 7, 8, 9})
 
 	// Chunk splits an array into multiple arrays,
-	// the size of each array is determined by <size>.
+	// the size of each array is determined by `size`.
 	// The last chunk may contain less than size elements.
 	fmt.Println(array.Chunk(2))
 
diff --git a/os/glog/glog.go b/os/glog/glog.go
index 089f853f7..a465a5b43 100644
--- a/os/glog/glog.go
+++ b/os/glog/glog.go
@@ -30,7 +30,7 @@ func init() {
 	SetDebug(defaultDebug)
 }
 
-// Default returns the default logger.
+// DefaultLogger returns the default logger.
 func DefaultLogger() *Logger {
 	return logger
 }
diff --git a/os/glog/glog_api.go b/os/glog/glog_api.go
index 830d6f64f..243a7b993 100644
--- a/os/glog/glog_api.go
+++ b/os/glog/glog_api.go
@@ -18,6 +18,7 @@ func Printf(format string, v ...interface{}) {
 	logger.Printf(format, v...)
 }
 
+// Println is alias of Print.
 // See Print.
 func Println(v ...interface{}) {
 	logger.Println(v...)
diff --git a/os/glog/glog_config.go b/os/glog/glog_config.go
index c38454495..6e4402dee 100644
--- a/os/glog/glog_config.go
+++ b/os/glog/glog_config.go
@@ -148,3 +148,8 @@ func SetLevelPrefixes(prefixes map[int]string) {
 func GetLevelPrefix(level int) string {
 	return logger.GetLevelPrefix(level)
 }
+
+// SetHandlers sets the logging handlers for default logger.
+func SetHandlers(handlers ...Handler) {
+	logger.SetHandlers(handlers...)
+}
diff --git a/os/glog/glog_logger.go b/os/glog/glog_logger.go
index 59d3d4f88..7f4dcbc91 100644
--- a/os/glog/glog_logger.go
+++ b/os/glog/glog_logger.go
@@ -62,6 +62,7 @@ func New() *Logger {
 		init:   gtype.NewBool(),
 		config: DefaultConfig(),
 	}
+	logger.config.Handlers = []Handler{defaultHandler}
 	return logger
 }
 
@@ -94,7 +95,7 @@ func (l *Logger) getFilePath(now time.Time) string {
 }
 
 // print prints <s> to defined writer, logging file or passed <std>.
-func (l *Logger) print(std io.Writer, lead string, values ...interface{}) {
+func (l *Logger) print(ctx context.Context, level int, values ...interface{}) {
 	// Lazy initialize for rotation feature.
 	// It uses atomic reading operation to enhance the performance checking.
 	// It here uses CAP for performance and concurrent safety.
@@ -111,69 +112,70 @@ func (l *Logger) print(std io.Writer, lead string, values ...interface{}) {
 	}
 
 	var (
-		now    = time.Now()
-		buffer = bytes.NewBuffer(nil)
+		now   = time.Now()
+		input = &HandlerInput{
+			logger: l,
+			index:  -1,
+			Ctx:    ctx,
+			Time:   now,
+			Level:  level,
+		}
 	)
 	if l.config.HeaderPrint {
 		// Time.
 		timeFormat := ""
 		if l.config.Flags&F_TIME_DATE > 0 {
-			timeFormat += "2006-01-02 "
+			timeFormat += "2006-01-02"
 		}
 		if l.config.Flags&F_TIME_TIME > 0 {
-			timeFormat += "15:04:05 "
+			if timeFormat != "" {
+				timeFormat += " "
+			}
+			timeFormat += "15:04:05"
 		}
 		if l.config.Flags&F_TIME_MILLI > 0 {
-			timeFormat += "15:04:05.000 "
+			if timeFormat != "" {
+				timeFormat += " "
+			}
+			timeFormat += "15:04:05.000"
 		}
 		if len(timeFormat) > 0 {
-			buffer.WriteString(now.Format(timeFormat))
-		}
-		// Lead string.
-		if len(lead) > 0 {
-			buffer.WriteString(lead)
-			if len(values) > 0 {
-				buffer.WriteByte(' ')
-			}
+			input.TimeFormat = now.Format(timeFormat)
 		}
+
+		// Level string.
+		input.LevelFormat = l.getLevelPrefixWithBrackets(level)
+
 		// Caller path and Fn name.
 		if l.config.Flags&(F_FILE_LONG|F_FILE_SHORT|F_CALLER_FN) > 0 {
-			callerPath := ""
 			callerFnName, path, line := gdebug.CallerWithFilter(pathFilterKey, l.config.StSkip)
 			if l.config.Flags&F_CALLER_FN > 0 {
-				buffer.WriteString(fmt.Sprintf(`[%s] `, callerFnName))
+				input.CallerFunc = fmt.Sprintf(`[%s]`, callerFnName)
 			}
 			if l.config.Flags&F_FILE_LONG > 0 {
-				callerPath = fmt.Sprintf(`%s:%d: `, path, line)
+				input.CallerPath = fmt.Sprintf(`%s:%d:`, path, line)
 			}
 			if l.config.Flags&F_FILE_SHORT > 0 {
-				callerPath = fmt.Sprintf(`%s:%d: `, gfile.Basename(path), line)
+				input.CallerPath = fmt.Sprintf(`%s:%d:`, gfile.Basename(path), line)
 			}
-			buffer.WriteString(callerPath)
-
 		}
 		// Prefix.
 		if len(l.config.Prefix) > 0 {
-			buffer.WriteString(l.config.Prefix + " ")
+			input.Prefix = l.config.Prefix
 		}
 	}
 	// Convert value to string.
-	var (
-		tempStr  = ""
-		valueStr = ""
-	)
-
-	if l.ctx != nil {
+	if ctx != nil {
 		// Tracing values.
-		spanCtx := trace.SpanContextFromContext(l.ctx)
+		spanCtx := trace.SpanContextFromContext(ctx)
 		if traceId := spanCtx.TraceID(); traceId.IsValid() {
-			buffer.WriteString(fmt.Sprintf("{TraceID:%s} ", traceId.String()))
+			input.CtxStr = "{TraceID:" + traceId.String() + "}"
 		}
 		// Context values.
 		if len(l.config.CtxKeys) > 0 {
 			ctxStr := ""
 			for _, key := range l.config.CtxKeys {
-				if v := l.ctx.Value(key); v != nil {
+				if v := ctx.Value(key); v != nil {
 					if ctxStr != "" {
 						ctxStr += ", "
 					}
@@ -181,51 +183,52 @@ func (l *Logger) print(std io.Writer, lead string, values ...interface{}) {
 				}
 			}
 			if ctxStr != "" {
-				buffer.WriteString(fmt.Sprintf("{%s} ", ctxStr))
+				input.CtxStr += "{" + ctxStr + "}"
 			}
 		}
 	}
-
+	var tempStr string
 	for _, v := range values {
 		tempStr = gconv.String(v)
-		if len(valueStr) > 0 {
-			if valueStr[len(valueStr)-1] == '\n' {
+		if len(input.Content) > 0 {
+			if input.Content[len(input.Content)-1] == '\n' {
 				// Remove one blank line(\n\n).
 				if tempStr[0] == '\n' {
-					valueStr += tempStr[1:]
+					input.Content += tempStr[1:]
 				} else {
-					valueStr += tempStr
+					input.Content += tempStr
 				}
 			} else {
-				valueStr += " " + tempStr
+				input.Content += " " + tempStr
 			}
 		} else {
-			valueStr = tempStr
+			input.Content = tempStr
 		}
 	}
-	buffer.WriteString(valueStr + "\n")
 	if l.config.Flags&F_ASYNC > 0 {
+		input.IsAsync = true
 		err := asyncPool.Add(func() {
-			l.printToWriter(now, std, buffer)
+			input.Next()
 		})
 		if err != nil {
 			intlog.Error(err)
 		}
 	} else {
-		l.printToWriter(now, std, buffer)
+		input.Next()
 	}
 }
 
 // printToWriter writes buffer to writer.
-func (l *Logger) printToWriter(now time.Time, std io.Writer, buffer *bytes.Buffer) {
+func (l *Logger) printToWriter(ctx context.Context, input *HandlerInput) {
+	buffer := input.Buffer()
 	if l.config.Writer == nil {
 		// Output content to disk file.
 		if l.config.Path != "" {
-			l.printToFile(now, buffer)
+			l.printToFile(input.Time, buffer)
 		}
 		// Allow output to stdout?
 		if l.config.StdoutPrint {
-			if _, err := std.Write(buffer.Bytes()); err != nil {
+			if _, err := os.Stdout.Write(buffer.Bytes()); err != nil {
 				intlog.Error(err)
 			}
 		}
@@ -238,9 +241,9 @@ func (l *Logger) printToWriter(now time.Time, std io.Writer, buffer *bytes.Buffe
 }
 
 // printToFile outputs logging content to disk file.
-func (l *Logger) printToFile(now time.Time, buffer *bytes.Buffer) {
+func (l *Logger) printToFile(t time.Time, buffer *bytes.Buffer) {
 	var (
-		logFilePath   = l.getFilePath(now)
+		logFilePath   = l.getFilePath(t)
 		memoryLockKey = "glog.printToFile:" + logFilePath
 	)
 	gmlock.Lock(memoryLockKey)
@@ -249,7 +252,7 @@ func (l *Logger) printToFile(now time.Time, buffer *bytes.Buffer) {
 	// Rotation file size checks.
 	if l.config.RotateSize > 0 {
 		if gfile.Size(logFilePath) > l.config.RotateSize {
-			l.rotateFileBySize(now)
+			l.rotateFileBySize(t)
 		}
 	}
 	// Logging content outputting to disk file.
@@ -280,20 +283,29 @@ func (l *Logger) getFilePointer(path string) *gfpool.File {
 	return file
 }
 
+// getCtx returns the context which is set through chaining operations.
+// It returns an empty context if no context set previously.
+func (l *Logger) getCtx() context.Context {
+	if l.ctx != nil {
+		return l.ctx
+	}
+	return context.TODO()
+}
+
 // printStd prints content <s> without stack.
-func (l *Logger) printStd(lead string, value ...interface{}) {
-	l.print(os.Stdout, lead, value...)
+func (l *Logger) printStd(level int, value ...interface{}) {
+	l.print(l.getCtx(), level, value...)
 }
 
 // printStd prints content <s> with stack check.
-func (l *Logger) printErr(lead string, value ...interface{}) {
+func (l *Logger) printErr(level int, value ...interface{}) {
 	if l.config.StStatus == 1 {
 		if s := l.GetStack(); s != "" {
 			value = append(value, "\nStack:\n"+s)
 		}
 	}
 	// In matter of sequence, do not use stderr here, but use the same stdout.
-	l.print(os.Stdout, lead, value...)
+	l.print(l.getCtx(), level, value...)
 }
 
 // format formats <values> using fmt.Sprintf.
diff --git a/os/glog/glog_logger_api.go b/os/glog/glog_logger_api.go
index f7769630d..321da0752 100644
--- a/os/glog/glog_logger_api.go
+++ b/os/glog/glog_logger_api.go
@@ -14,13 +14,13 @@ import (
 // Print prints <v> with newline using fmt.Sprintln.
 // The parameter <v> can be multiple variables.
 func (l *Logger) Print(v ...interface{}) {
-	l.printStd("", v...)
+	l.printStd(LEVEL_NONE, v...)
 }
 
 // Printf prints <v> with format <format> using fmt.Sprintf.
 // The parameter <v> can be multiple variables.
 func (l *Logger) Printf(format string, v ...interface{}) {
-	l.printStd("", l.format(format, v...))
+	l.printStd(LEVEL_NONE, l.format(format, v...))
 }
 
 // Println is alias of Print.
@@ -31,53 +31,53 @@ func (l *Logger) Println(v ...interface{}) {
 
 // Fatal prints the logging content with [FATA] header and newline, then exit the current process.
 func (l *Logger) Fatal(v ...interface{}) {
-	l.printErr(l.getLevelPrefixWithBrackets(LEVEL_FATA), v...)
+	l.printErr(LEVEL_FATA, v...)
 	os.Exit(1)
 }
 
 // Fatalf prints the logging content with [FATA] header, custom format and newline, then exit the current process.
 func (l *Logger) Fatalf(format string, v ...interface{}) {
-	l.printErr(l.getLevelPrefixWithBrackets(LEVEL_FATA), l.format(format, v...))
+	l.printErr(LEVEL_FATA, l.format(format, v...))
 	os.Exit(1)
 }
 
 // Panic prints the logging content with [PANI] header and newline, then panics.
 func (l *Logger) Panic(v ...interface{}) {
-	l.printErr(l.getLevelPrefixWithBrackets(LEVEL_PANI), v...)
+	l.printErr(LEVEL_PANI, v...)
 	panic(fmt.Sprint(v...))
 }
 
 // Panicf prints the logging content with [PANI] header, custom format and newline, then panics.
 func (l *Logger) Panicf(format string, v ...interface{}) {
-	l.printErr(l.getLevelPrefixWithBrackets(LEVEL_PANI), l.format(format, v...))
+	l.printErr(LEVEL_PANI, l.format(format, v...))
 	panic(l.format(format, v...))
 }
 
 // Info prints the logging content with [INFO] header and newline.
 func (l *Logger) Info(v ...interface{}) {
 	if l.checkLevel(LEVEL_INFO) {
-		l.printStd(l.getLevelPrefixWithBrackets(LEVEL_INFO), v...)
+		l.printStd(LEVEL_INFO, v...)
 	}
 }
 
 // Infof prints the logging content with [INFO] header, custom format and newline.
 func (l *Logger) Infof(format string, v ...interface{}) {
 	if l.checkLevel(LEVEL_INFO) {
-		l.printStd(l.getLevelPrefixWithBrackets(LEVEL_INFO), l.format(format, v...))
+		l.printStd(LEVEL_INFO, l.format(format, v...))
 	}
 }
 
 // Debug prints the logging content with [DEBU] header and newline.
 func (l *Logger) Debug(v ...interface{}) {
 	if l.checkLevel(LEVEL_DEBU) {
-		l.printStd(l.getLevelPrefixWithBrackets(LEVEL_DEBU), v...)
+		l.printStd(LEVEL_DEBU, v...)
 	}
 }
 
 // Debugf prints the logging content with [DEBU] header, custom format and newline.
 func (l *Logger) Debugf(format string, v ...interface{}) {
 	if l.checkLevel(LEVEL_DEBU) {
-		l.printStd(l.getLevelPrefixWithBrackets(LEVEL_DEBU), l.format(format, v...))
+		l.printStd(LEVEL_DEBU, l.format(format, v...))
 	}
 }
 
@@ -85,7 +85,7 @@ func (l *Logger) Debugf(format string, v ...interface{}) {
 // It also prints caller stack info if stack feature is enabled.
 func (l *Logger) Notice(v ...interface{}) {
 	if l.checkLevel(LEVEL_NOTI) {
-		l.printStd(l.getLevelPrefixWithBrackets(LEVEL_NOTI), v...)
+		l.printStd(LEVEL_NOTI, v...)
 	}
 }
 
@@ -93,7 +93,7 @@ func (l *Logger) Notice(v ...interface{}) {
 // It also prints caller stack info if stack feature is enabled.
 func (l *Logger) Noticef(format string, v ...interface{}) {
 	if l.checkLevel(LEVEL_NOTI) {
-		l.printStd(l.getLevelPrefixWithBrackets(LEVEL_NOTI), l.format(format, v...))
+		l.printStd(LEVEL_NOTI, l.format(format, v...))
 	}
 }
 
@@ -101,7 +101,7 @@ func (l *Logger) Noticef(format string, v ...interface{}) {
 // It also prints caller stack info if stack feature is enabled.
 func (l *Logger) Warning(v ...interface{}) {
 	if l.checkLevel(LEVEL_WARN) {
-		l.printStd(l.getLevelPrefixWithBrackets(LEVEL_WARN), v...)
+		l.printStd(LEVEL_WARN, v...)
 	}
 }
 
@@ -109,7 +109,7 @@ func (l *Logger) Warning(v ...interface{}) {
 // It also prints caller stack info if stack feature is enabled.
 func (l *Logger) Warningf(format string, v ...interface{}) {
 	if l.checkLevel(LEVEL_WARN) {
-		l.printStd(l.getLevelPrefixWithBrackets(LEVEL_WARN), l.format(format, v...))
+		l.printStd(LEVEL_WARN, l.format(format, v...))
 	}
 }
 
@@ -117,7 +117,7 @@ func (l *Logger) Warningf(format string, v ...interface{}) {
 // It also prints caller stack info if stack feature is enabled.
 func (l *Logger) Error(v ...interface{}) {
 	if l.checkLevel(LEVEL_ERRO) {
-		l.printErr(l.getLevelPrefixWithBrackets(LEVEL_ERRO), v...)
+		l.printErr(LEVEL_ERRO, v...)
 	}
 }
 
@@ -125,7 +125,7 @@ func (l *Logger) Error(v ...interface{}) {
 // It also prints caller stack info if stack feature is enabled.
 func (l *Logger) Errorf(format string, v ...interface{}) {
 	if l.checkLevel(LEVEL_ERRO) {
-		l.printErr(l.getLevelPrefixWithBrackets(LEVEL_ERRO), l.format(format, v...))
+		l.printErr(LEVEL_ERRO, l.format(format, v...))
 	}
 }
 
@@ -133,7 +133,7 @@ func (l *Logger) Errorf(format string, v ...interface{}) {
 // It also prints caller stack info if stack feature is enabled.
 func (l *Logger) Critical(v ...interface{}) {
 	if l.checkLevel(LEVEL_CRIT) {
-		l.printErr(l.getLevelPrefixWithBrackets(LEVEL_CRIT), v...)
+		l.printErr(LEVEL_CRIT, v...)
 	}
 }
 
@@ -141,7 +141,7 @@ func (l *Logger) Critical(v ...interface{}) {
 // It also prints caller stack info if stack feature is enabled.
 func (l *Logger) Criticalf(format string, v ...interface{}) {
 	if l.checkLevel(LEVEL_CRIT) {
-		l.printErr(l.getLevelPrefixWithBrackets(LEVEL_CRIT), l.format(format, v...))
+		l.printErr(LEVEL_CRIT, l.format(format, v...))
 	}
 }
 
diff --git a/os/glog/glog_logger_config.go b/os/glog/glog_logger_config.go
index f28e6862a..6b00a6afd 100644
--- a/os/glog/glog_logger_config.go
+++ b/os/glog/glog_logger_config.go
@@ -22,6 +22,7 @@ import (
 
 // Config is the configuration object for logger.
 type Config struct {
+	Handlers             []Handler      `json:"-"`                    // Logger handlers which implement feature similar as middleware.
 	Writer               io.Writer      `json:"-"`                    // Customized io.Writer.
 	Flags                int            `json:"flags"`                // Extra flags for logging output features.
 	Path                 string         `json:"path"`                 // Logging directory path.
@@ -246,3 +247,8 @@ func (l *Logger) SetHeaderPrint(enabled bool) {
 func (l *Logger) SetPrefix(prefix string) {
 	l.config.Prefix = prefix
 }
+
+// SetHandlers sets the logging handlers for current logger.
+func (l *Logger) SetHandlers(handlers ...Handler) {
+	l.config.Handlers = append(handlers, defaultHandler)
+}
diff --git a/os/glog/glog_logger_handler.go b/os/glog/glog_logger_handler.go
new file mode 100644
index 000000000..1991cd547
--- /dev/null
+++ b/os/glog/glog_logger_handler.go
@@ -0,0 +1,78 @@
+// Copyright GoFrame Author(https://goframe.org). All Rights Reserved.
+//
+// This Source Code Form is subject to the terms of the MIT License.
+// If a copy of the MIT was not distributed with this file,
+// You can obtain one at https://github.com/gogf/gf.
+
+package glog
+
+import (
+	"bytes"
+	"context"
+	"time"
+)
+
+type Handler func(ctx context.Context, input *HandlerInput)
+
+type HandlerInput struct {
+	logger      *Logger
+	index       int
+	Ctx         context.Context
+	Time        time.Time
+	TimeFormat  string
+	Level       int
+	LevelFormat string
+	CallerFunc  string
+	CallerPath  string
+	CtxStr      string
+	Prefix      string
+	Content     string
+	IsAsync     bool
+}
+
+// defaultHandler is the default handler for logger.
+func defaultHandler(ctx context.Context, input *HandlerInput) {
+	input.logger.printToWriter(ctx, input)
+}
+
+func (i *HandlerInput) addStringToBuffer(buffer *bytes.Buffer, s string) {
+	if buffer.Len() > 0 {
+		buffer.WriteByte(' ')
+	}
+	buffer.WriteString(s)
+}
+
+func (i *HandlerInput) Buffer() *bytes.Buffer {
+	buffer := bytes.NewBuffer(nil)
+	buffer.WriteString(i.TimeFormat)
+	if i.LevelFormat != "" {
+		i.addStringToBuffer(buffer, i.LevelFormat)
+	}
+	if i.CallerFunc != "" {
+		i.addStringToBuffer(buffer, i.CallerFunc)
+	}
+	if i.CallerPath != "" {
+		i.addStringToBuffer(buffer, i.CallerPath)
+	}
+	if i.Prefix != "" {
+		i.addStringToBuffer(buffer, i.Prefix)
+	}
+	if i.CtxStr != "" {
+		i.addStringToBuffer(buffer, i.CtxStr)
+	}
+	if i.Content != "" {
+		i.addStringToBuffer(buffer, i.Content)
+	}
+	return buffer
+}
+
+func (i *HandlerInput) String() string {
+	return i.Buffer().String()
+}
+
+func (i *HandlerInput) Next() {
+	if len(i.logger.config.Handlers)-1 > i.index {
+		i.index++
+		i.logger.config.Handlers[i.index](i.Ctx, i)
+	}
+}
diff --git a/os/glog/glog_logger_level.go b/os/glog/glog_logger_level.go
index f9b5c28ed..a756bc6f8 100644
--- a/os/glog/glog_logger_level.go
+++ b/os/glog/glog_logger_level.go
@@ -18,6 +18,7 @@ const (
 	LEVEL_ALL  = LEVEL_DEBU | LEVEL_INFO | LEVEL_NOTI | LEVEL_WARN | LEVEL_ERRO | LEVEL_CRIT
 	LEVEL_DEV  = LEVEL_ALL
 	LEVEL_PROD = LEVEL_WARN | LEVEL_ERRO | LEVEL_CRIT
+	LEVEL_NONE = 0
 	LEVEL_DEBU = 1 << iota // 8
 	LEVEL_INFO             // 16
 	LEVEL_NOTI             // 32
diff --git a/os/glog/glog_z_unit_handler_test.go b/os/glog/glog_z_unit_handler_test.go
new file mode 100644
index 000000000..70acc0f5c
--- /dev/null
+++ b/os/glog/glog_z_unit_handler_test.go
@@ -0,0 +1,80 @@
+// Copyright GoFrame Author(https://goframe.org). All Rights Reserved.
+//
+// This Source Code Form is subject to the terms of the MIT License.
+// If a copy of the MIT was not distributed with this file,
+// You can obtain one at https://github.com/gogf/gf.
+
+package glog_test
+
+import (
+	"bytes"
+	"context"
+	"github.com/gogf/gf/container/garray"
+	"github.com/gogf/gf/os/glog"
+	"github.com/gogf/gf/test/gtest"
+	"github.com/gogf/gf/text/gstr"
+	"testing"
+)
+
+var arrayForHandlerTest1 = garray.NewStrArray()
+
+func customHandler1(ctx context.Context, input *glog.HandlerInput) {
+	arrayForHandlerTest1.Append(input.String())
+	input.Next()
+}
+
+func TestLogger_SetHandlers1(t *testing.T) {
+	gtest.C(t, func(t *gtest.T) {
+		w := bytes.NewBuffer(nil)
+		l := glog.NewWithWriter(w)
+		l.SetHandlers(customHandler1)
+		l.SetCtxKeys("Trace-Id", "Span-Id", "Test")
+		ctx := context.WithValue(context.Background(), "Trace-Id", "1234567890")
+		ctx = context.WithValue(ctx, "Span-Id", "abcdefg")
+
+		l.Ctx(ctx).Print(1, 2, 3)
+		t.Assert(gstr.Count(w.String(), "Trace-Id"), 1)
+		t.Assert(gstr.Count(w.String(), "1234567890"), 1)
+		t.Assert(gstr.Count(w.String(), "Span-Id"), 1)
+		t.Assert(gstr.Count(w.String(), "abcdefg"), 1)
+		t.Assert(gstr.Count(w.String(), "1 2 3"), 1)
+
+		t.Assert(arrayForHandlerTest1.Len(), 1)
+		t.Assert(gstr.Count(arrayForHandlerTest1.At(0), "Trace-Id"), 1)
+		t.Assert(gstr.Count(arrayForHandlerTest1.At(0), "1234567890"), 1)
+		t.Assert(gstr.Count(arrayForHandlerTest1.At(0), "Span-Id"), 1)
+		t.Assert(gstr.Count(arrayForHandlerTest1.At(0), "abcdefg"), 1)
+		t.Assert(gstr.Count(arrayForHandlerTest1.At(0), "1 2 3"), 1)
+	})
+}
+
+var arrayForHandlerTest2 = garray.NewStrArray()
+
+func customHandler2(ctx context.Context, input *glog.HandlerInput) {
+	arrayForHandlerTest2.Append(input.String())
+}
+
+func TestLogger_SetHandlers2(t *testing.T) {
+	gtest.C(t, func(t *gtest.T) {
+		w := bytes.NewBuffer(nil)
+		l := glog.NewWithWriter(w)
+		l.SetHandlers(customHandler2)
+		l.SetCtxKeys("Trace-Id", "Span-Id", "Test")
+		ctx := context.WithValue(context.Background(), "Trace-Id", "1234567890")
+		ctx = context.WithValue(ctx, "Span-Id", "abcdefg")
+
+		l.Ctx(ctx).Print(1, 2, 3)
+		t.Assert(gstr.Count(w.String(), "Trace-Id"), 0)
+		t.Assert(gstr.Count(w.String(), "1234567890"), 0)
+		t.Assert(gstr.Count(w.String(), "Span-Id"), 0)
+		t.Assert(gstr.Count(w.String(), "abcdefg"), 0)
+		t.Assert(gstr.Count(w.String(), "1 2 3"), 0)
+
+		t.Assert(arrayForHandlerTest2.Len(), 1)
+		t.Assert(gstr.Count(arrayForHandlerTest2.At(0), "Trace-Id"), 1)
+		t.Assert(gstr.Count(arrayForHandlerTest2.At(0), "1234567890"), 1)
+		t.Assert(gstr.Count(arrayForHandlerTest2.At(0), "Span-Id"), 1)
+		t.Assert(gstr.Count(arrayForHandlerTest2.At(0), "abcdefg"), 1)
+		t.Assert(gstr.Count(arrayForHandlerTest2.At(0), "1 2 3"), 1)
+	})
+}