自己实现的Java数据序列化与反序列化
序列化与反序列化，
String类型最大字节长度65535，也就是64k，大概能写21000个汉字，
byte\[\]类型最大字节长度是Integer.Max,理论支持2G大小，
单个数据包长度理论支持2G，请根据你的内存量力而行，
```
package com.itshidu.io;
import java.nio.charset.Charset;
import java.util.Arrays;
import com.itshidu.util.BitConverter;
/**
* 发送的请求数据
* 数据类型：String_255=0;String_65535=1;Int8=2;Int16=3;Int32=4;Int64=5;Float=6;Double=7;Boolean=8;Char=9;Byte[]=10;
* String类型数值最大65535字节（UTF8字符集，每个汉字3字节）
* @author Master.Xia
*/
public class NetMessage{
public static byte[] Concat(byte[]... bs) {
int len = 0,idx=0;
for(byte[] b:bs)len+=b.length;
byte[] buffer = new byte[len];
for(byte[] b:bs) {
System.arraycopy(b,0, buffer, idx, b.length);
idx+=b.length;
}
return buffer;
}
public int code; //0-255
public int subCode; //0-255
public Object[] data;
public byte[] GetBytes() {
byte[] buffer = new byte[]{(byte)(code-128),(byte)(subCode-128)};
buffer = Concat(buffer,new byte[] {(byte)data.length});
for(int i=0;i<data.length;i++) {
if(data[i] instanceof String) { //String
byte[] typeBytes = null;
byte[] lenBytes = null;
byte[] strBytes=((String)data[i]).getBytes(Charset.forName("UTF-8"));
if(strBytes.length<=255) {
typeBytes = new byte[]{(byte)0};
lenBytes=new byte[]{(byte)(strBytes.length-128)};
}else if(strBytes.length<=65535) {
typeBytes = new byte[]{(byte)1};
lenBytes=BitConverter.GetBytes((short)(strBytes.length-32768));
}else {
throw new RuntimeException("String Byte Length Out of Bounds:"+strBytes.length);
}
buffer = Concat(buffer,typeBytes,lenBytes,strBytes);
}else if(data[i] instanceof Byte) { //Int8
byte[] typeBytes = new byte[]{(byte)2};
byte[] dataBytes = new byte[]{(byte)data[i]};
buffer = Concat(buffer,typeBytes,dataBytes);
}else if(data[i] instanceof Short) { //Int16
byte[] typeBytes = new byte[]{(byte)3};
byte[] dataBytes=BitConverter.GetBytes((short)data[i]);
buffer = Concat(buffer,typeBytes,dataBytes);
}else if(data[i] instanceof Integer) { //Int32
byte[] typeBytes = new byte[]{(byte)4};
byte[] dataBytes=BitConverter.GetBytes((int)data[i]);
buffer = Concat(buffer,typeBytes,dataBytes);
}else if(data[i] instanceof Long) { //Int64
byte[] typeBytes = new byte[]{(byte)5};
byte[] dataBytes=BitConverter.GetBytes((long)data[i]);
buffer = Concat(buffer,typeBytes,dataBytes);
}else if(data[i] instanceof Float) { //Float
byte[] typeBytes = new byte[]{(byte)6};
byte[] dataBytes = BitConverter.GetBytes((float)data[i]);
buffer = Concat(buffer,typeBytes,dataBytes);
}else if(data[i] instanceof Double) { //Double
byte[] typeBytes = new byte[]{(byte)7};
byte[] dataBytes = BitConverter.GetBytes(Double.doubleToLongBits((double)data[i]));
buffer = Concat(buffer,typeBytes,dataBytes);
}else if(data[i] instanceof Boolean) { //Boolean
byte[] typeBytes = new byte[]{(byte)8};
byte[] dataBytes = new byte[]{(byte)(((boolean)data[i])? 1:0)};
buffer = Concat(buffer,typeBytes,dataBytes);
}else if(data[i] instanceof Character) {//Char
byte[] typeBytes = new byte[]{(byte)9};
byte[] dataBytes = new String(new char[] {(char)data[i]}).getBytes(Charset.forName("UTF-8"));
byte[] lenBytes = new byte[] { (byte)dataBytes.length };
buffer = Concat(buffer,typeBytes,lenBytes,dataBytes);
}else if(data[i] instanceof byte[]&##124;&##124;data[i] instanceof Byte[]) { //byte[]:&##124;Type:1byte&##124;DataLen:4byte&##124;Data&##124;
byte[] typeBytes = new byte[]{(byte)10};
byte[] dataBytes = null;
if(data[i] instanceof Byte[]){
Byte[] bs1 = (Byte[])data[i];
dataBytes = new byte[bs1.length];
for(int m=0;m<bs1.length;m++){
dataBytes[m]=(byte)bs1[m];
}
}else {
dataBytes = (byte[])data[i];
}
byte[] lenBytes=BitConverter.GetBytes(dataBytes.length);
buffer = Concat(buffer,typeBytes,lenBytes,dataBytes);
}
}
return buffer;
}
public NetMessage(byte[] bytes){
this.code = bytes[0]+128;
this.subCode = bytes[1]+128;
int count = BitConverter.ByteToInt(bytes[2]);
int index = 3;
this.data = new Object[count];
for(int i=0;i<count;i++) {
int argType = BitConverter.ByteToInt(bytes[index++]);
if(argType==0) { //String_255
int len = BitConverter.ByteToInt((byte)(128+bytes[index++]));
data[i] = new String(bytes,index,len,Charset.forName("UTF-8"));
index += len;
}else if(argType==1) { //String_65535
int len = BitConverter.ToInt16(bytes, index)+32768;
index += 2;
data[i] = new String(bytes,index,len,Charset.forName("UTF-8"));
index += len;
}else if(argType==2) { //Byte
data[i] = BitConverter.ByteToInt(bytes[index++]);
}else if(argType==3) { //Short
data[i] = BitConverter.ToInt16(bytes, index);
index += 2;
}else if(argType==4) { //Int
data[i] = BitConverter.ToInt32(bytes, index);
index += 4;
}else if(argType==5) { //Long
data[i] = BitConverter.ToInt64(bytes, index);
index += 8;
}else if(argType==6) { //Float
data[i] = BitConverter.ToFloat(bytes, index);
index += 4;
}else if(argType==7) { //Double
data[i] = Double.longBitsToDouble(BitConverter.ToInt64(bytes, index));
index+=8;
}else if(argType==8) { //Boolean
data[i]=(bytes[index++]==0x00)? false:true;
}else if(argType==9) { //Char
Charset charset = Charset.forName("UTF-8");
int len = BitConverter.ByteToInt(bytes[index++]);
data[i] = new String(bytes,index,len,charset).toCharArray()[0];
index += len;
}else if(argType==10) { //Byte[]
int len6 = BitConverter.ToInt32(bytes, index);
index += 4;
data[i] = new byte[len6];
System.arraycopy(bytes, index, data[i], 0, len6);
index += len6;
}else {
System.out.println("无法识别的类型码："+argType);
}
}
}
public byte[] pack() {
byte[] dataBytes = this.GetBytes();
byte[] lenBytes = BitConverter.GetBytes(dataBytes.length);
return Concat(lenBytes,dataBytes);
}
public NetMessage(byte[] bytes,int offset,int length) {
this(Arrays.copyOfRange(bytes, offset, offset+length));
}
public NetMessage(int reqCode,int subCode,Object...objects) {
this.code = reqCode;
this.subCode = subCode;
this.data = objects;
}
public NetMessage(int reqCode,int subCode) {
this.code = reqCode;
this.subCode = subCode;
}
public NetMessage(int reqCode) {
this.code = reqCode;
}
public static void main(String[] args) {
NetMessage a = new NetMessage(
(byte)0,(byte)200,(byte)100,(short)1000,(int)10000,(long)100000,1.414f,3.141592654,true,false,'@','哈'
,"HelloWorld".getBytes()
,"中华人民共和国万岁".getBytes()
,123
);
byte[] bs = a.GetBytes();
NetMessage b = new NetMessage(bs);
System.out.println("ReqCode:"+b.code);
System.out.println("SubCode:"+b.subCode);
for(Object o : b.data) {
System.out.println(o);
}
System.out.println(new String((byte[])b.data[b.data.length-2]));
}
}
```
网络传输的基础就是字节，所以无论什么语言，只要按照此处的规则进行对应，都可以相互转化。