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https://msgpack.org/ It's like JSON.but fast and small. 说明 msg-pack-info.pngMessagePack 是一个高效的二进制序列化格式。它让你像JSON一样可以在各种语言之间交换数据。但是它比JSON更快、更小。小的整数会被编码成一个字节，短的字符串仅仅只需要比它的长度多一字节的大小。 原有json长度：27 byte msgPack长度：18 byte 压缩原理官方说明 布尔bool 值可以用1byte表示 false: +--------+ | 0xc2 | +--------+ true: +--------+ | 0xc3 | +--------+ 无长度第一个字节特定标识 int 8 stores a 8-bit signed integer +--------+--------+ | 0xd0 |ZZZZZZZZ| +--------+--------+ int 16 stores a 16-bit big-endian signed integer +--------+--------+--------+ | 0xd1 |ZZZZZZZZ|ZZZZZZZZ| +--------+--------+--------+ int 32 stores a 32-bit big-endian signed integer +--------+--------+--------+--------+--------+ | 0xd2 |ZZZZZZZZ|ZZZZZZZZ|ZZZZZZZZ|ZZZZZZZZ| +--------+--------+--------+--------+--------+ int 64 stores a 64-bit big-endian signed integer +--------+--------+--------+--------+--------+--------+--------+--------+--------+ | 0xd3 |ZZZZZZZZ|ZZZZZZZZ|ZZZZZZZZ|ZZZZZZZZ|ZZZZZZZZ|ZZZZZZZZ|ZZZZZZZZ|ZZZZZZZZ| +--------+--------+--------+--------+--------+--------+--------+--------+--------+ 不定长主要是字符串、数组、二进制数据等 fixstr stores a byte array whose length is upto 31 bytes: +--------+========+ |101XXXXX| data | +--------+========+ str 8 stores a byte array whose length is upto (2^8)-1 bytes: +--------+--------+========+ | 0xd9 |YYYYYYYY| data | +--------+--------+========+ str 16 stores a byte array whose length is upto (2^16)-1 bytes: +--------+--------+--------+========+ | 0xda |ZZZZZZZZ|ZZZZZZZZ| data | +--------+--------+--------+========+ str 32 stores a byte array whose length is upto (2^32)-1 bytes: +--------+--------+--------+--------+--------+========+ | 0xdb |AAAAAAAA|AAAAAAAA|AAAAAAAA|AAAAAAAA| data | +--------+--------+--------+--------+--------+========+ 高级结构MAP结构 fixmap stores a map whose length is upto 15 elements +--------+~~~~~~~~~~~~~~~~~+ |1000XXXX| N*2 objects | +--------+~~~~~~~~~~~~~~~~~+ map 16 stores a map whose length is upto (2^16)-1 elements +--------+--------+--------+~~~~~~~~~~~~~~~~~+ | 0xde |YYYYYYYY|YYYYYYYY| N*2 objects | +--------+--------+--------+~~~~~~~~~~~~~~~~~+ map 32 stores a map whose length is upto (2^32)-1 elements +--------+--------+--------+--------+--------+~~~~~~~~~~~~~~~~~+ | 0xdf |ZZZZZZZZ|ZZZZZZZZ|ZZZZZZZZ|ZZZZZZZZ| N*2 objects | +--------+--------+--------+--------+--------+~~~~~~~~~~~~~~~~~+ where * XXXX is a 4-bit unsigned integer which represents N * YYYYYYYY_YYYYYYYY is a 16-bit big-endian unsigned integer which represents N * ZZZZZZZZ_ZZZZZZZZ_ZZZZZZZZ_ZZZZZZZZ is a 32-bit big-endian unsigned integer which represents N * N is the size of a map * odd elements in objects are keys of a map * the next element of a key is its associated value 使用导入包 repositories { mavenCentral() } dependencies { compile 'org.msgpack:msgpack-core:(version)' }数据打包 try { MessageBufferPacker packer = MessagePack.newDefaultBufferPacker(); packer .packInt(1) .packString("leo"); // pack arrays int[] arr = new int[] {3, 5, 1, 0, -1, 255}; packer.packArrayHeader(arr.length); for (int v : arr) { packer.packInt(v); } // pack map (key -> value) elements // the number of (key, value) pairs packer.packMapHeader(2); // Put "apple" -> 1 packer.packString("apple"); packer.packInt(1); // Put "banana" -> 2 packer.packString("banana"); packer.packInt(2); // pack binary data byte[] ba = new byte[] {1, 2, 3, 4}; packer.packBinaryHeader(ba.length); packer.writePayload(ba); packer.close(); } catch (IOException e) { }如何对上面的数据解包呢 MessageUnpacker unpacker = MessagePack.newDefaultUnpacker(packer.toMessageBuffer().array()); int id = unpacker.unpackInt(); String name = unpacker.unpackString(); System.out.print(id); System.out.print(name); int numPhones = unpacker.unpackArrayHeader(); String[] phones = new String[numPhones]; for (int i = 0; i < numPhones; ++i) { phones[i] = unpacker.unpackString(); } int maplen = unpacker.unpackMapHeader(); for (int j = 0; j < maplen; j++) { unpacker.unpackString(); unpacker.unpackInt(); } unpacker.close(); 打包POJO官方推荐使用 msgpack-jackson 导包 dependencies { compile 'org.msgpack:jackson-dataformat-msgpack:0.8.20' }实体类 public static class MyMessage implements Serializable { public String name; public double version; public MyMessage(String name, double version) { this.name = name; this.version = version; } public MyMessage(){} }按照官方文档写打包/解包代码 ObjectMapper objectMapper = new ObjectMapper(new MessagePackFactory()); MyMessage myMessage = new MyMessage("remer", 1111); byte[] bytes = objectMapper.writeValueAsBytes(myMessage); MyMessage deserialized = objectMapper.readValue(bytes, MyMessage.class); System.out.print(deserialized.name); 结论 MsgPack产生的数据更小，从而在数据传输过程中网络压力更小 MsgPack兼容性差，必须按照顺序保存字段 MsgPack是二进制序列化格式，兼容跨语言 参考msgpack Quick Start msgpack msgpack-jackson Java JSON Tutorial msgpack简介和使用 MsgPack是何方神圣 |
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