2018-01-18 12:02:56 +08:00
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package main
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import (
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2019-04-03 00:03:46 +08:00
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"fmt"
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2019-07-29 21:01:19 +08:00
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"github.com/gogf/gf/encoding/gbinary"
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2018-01-18 12:02:56 +08:00
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)
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func main() {
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2019-04-03 00:03:46 +08:00
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// Meta元数据文件数据结构：[键名哈希64(64bit,8byte) 键名长度(8bit,1byte) 键值长度(24bit,3byte) 数据文件偏移量(40bit,5byte)](变长)
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hash := 521369841259754125
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klen := 12
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vlen := 35535
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offset := 80000000
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2018-01-18 12:02:56 +08:00
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2019-04-03 00:03:46 +08:00
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// 编码
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bits := make([]gbinary.Bit, 0)
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bits = gbinary.EncodeBits(bits, hash, 64)
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bits = gbinary.EncodeBits(bits, klen, 8)
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bits = gbinary.EncodeBits(bits, vlen, 24)
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bits = gbinary.EncodeBits(bits, offset, 40)
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buffer := gbinary.EncodeBitsToBytes(bits)
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fmt.Println("meta length:", len(buffer))
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2018-01-18 12:02:56 +08:00
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2019-04-03 00:03:46 +08:00
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/* 文件存储及数据查询过程忽略，这里只展示元数据编码/解码示例 */
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2018-01-18 22:14:12 +08:00
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2019-04-03 00:03:46 +08:00
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// 解码
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metabits := gbinary.DecodeBytesToBits(buffer)
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fmt.Println("hash :", gbinary.DecodeBits(metabits[0:64]))
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fmt.Println("klen :", gbinary.DecodeBits(metabits[64:72]))
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fmt.Println("vlen :", gbinary.DecodeBits(metabits[72:96]))
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fmt.Println("offset:", gbinary.DecodeBits(metabits[96:136]))
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2018-01-18 12:02:56 +08:00
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}
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