今天自己实现了下TCP处理粘包的问题 TCP

用的是netty 的TCP服务框架 具体代码实现

package com.tongfang.forward.server.handler;

import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.io.PrintWriter;

import io.netty.buffer.ByteBuf;
import io.netty.channel.ChannelHandlerAdapter;
import io.netty.channel.ChannelHandlerContext;

public class MyTcpHandler  extends ChannelHandlerAdapter {
	
	
	static int count = 1;
	byte[] bigdata=new byte[0];
	public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
		 if (msg instanceof ByteBuf) {
			 ByteBuf data = (ByteBuf) msg;
			 int bytes = data.readableBytes();
			 byte[] temp = new byte[bytes];
			 data.readBytes(temp);
			 //将读取到的字节保存
			 bigdata = combineByteArray(bigdata,temp);
			 //如果不满足协议最少4个字节的话就不处理
			 if(bigdata.length< 4){
				 System.out.println("不满足协议要求最少4个字节");
				 return;
			 }
			 //我这边定义的协议头是4个字节
			 byte[] lengByte = new byte[4];
			 System.arraycopy(bigdata, 0, lengByte, 0, 4);
			 //获取内容长度
			 int length  = bytesToInt(lengByte);
			 System.out.println("协议长度为:"+length);
			 if(length > bigdata.length){
				 System.out.println("不满足协议长度要求要求");
				 return;
			 }
			 //判断获取到的数据能解析出来几个
			 int j = bigdata.length%(length+4)>0?bigdata.length/(length+4)-1:bigdata.length/(length+4);
			 for(int i= 0; i < j; i++){
				 byte[] head = new byte[4];
				 //获取长度
				 System.arraycopy(bigdata, 0, head, 0, 4);
				 int tempLength = bytesToInt(head);
				 byte[] temp2 = new byte[tempLength];
				 //获取内容
				 System.arraycopy(bigdata, 4, temp2, 0, tempLength);
				 String body = new String(temp2, "UTF-8"); 
				 export(body,count);
				 //去掉内容
				 bigdata = copyNewAry(bigdata,tempLength+4,bigdata.length-tempLength-4);
				 count++;
			 }
			 
		 }
	}
	
	
public void export(String str,int count){
		
		FileWriter fw = null;
		try {
			File f=new File("E:\\data"+count+".txt");
			
			if(!f.exists()){  
			    f.createNewFile();  
			 } 
			fw = new FileWriter(f, true);
			PrintWriter pw = new PrintWriter(fw);
			pw.println(str);
			pw.flush();
			fw.flush();
			pw.close();
			fw.close();
			System.out.println("写入完成···");
		} catch (IOException e) {
			e.printStackTrace();
		}
		
	}
	
	private  byte[] copyNewAry(byte[] array,int start,int length){
		byte[] newAry = new byte[length];
		System.arraycopy(array, start, newAry, 0, newAry.length);  
		return newAry;
	}
	
	
	
	
	
	private static byte[] combineByteArray(byte[] array1, byte[] array2) {  
        byte[] combined = new byte[array1.length + array2.length];  
        System.arraycopy(array1, 0, combined, 0, array1.length);  
        System.arraycopy(array2, 0, combined, array1.length, array2.length);  
        return combined;  
    }  
	
	public int bytesToInt(byte[] bArr) {    
        if(bArr.length!=4){    
            return -1;    
        }    
        return (int) ((((bArr[0] & 0xff) << 24)      
                   | ((bArr[1] & 0xff) << 16)      
                   | ((bArr[2] & 0xff) << 8)  
                   | ((bArr[3] & 0xff) << 0)));     
	}  
	
	public static void main(String[] args) {
		System.out.println(1024%252);
	}
}