Scoket通信

Scoket通信 1. socket介绍

socket编程是网络常用的编程，我们通过在网络中创建socket关键字来实现网络间的通信

2. 编码示例 服务端：

package cn.com.gs.demo;

import cn.com.gs.common.socket.BasicCommunicator;
import cn.com.gs.common.util.StringUtil;

import java.net.ServerSocket;
import java.net.Socket;


public class SocketServerTest {

    public static void main(String[] args) throws Exception {
        // 1. 创建套接字，绑定端口并监听
        ServerSocket server = new ServerSocket(9000);
        // 2. 阻塞，直到有客户端连接
        System.out.println("你不来，我不走，风里雨里一直等你...");
        Socket socket = server.accept();
        // 3. 接收客户端消息，并回复
        BasicCommunicator communicator = new BasicCommunicator(socket);

        // todo 整合实际业务，编写一个处理器，将请求转到实际业务层，并拿到业务层处理结果，响应给客户端
        // 参考NetSeal AppServer 的 SocketListener和SocketConnectionHandler
        byte[] recv = communicator.recv();
        System.out.println("服务端接收到的信息：" + StringUtil.getString(recv));

        String message = "Bye";
        communicator.send(StringUtil.getBytes(message));

        // 4. 关闭连接
        socket.close();

    }

}

客户端

package cn.com.gs.demo;

import cn.com.gs.common.socket.BasicCommunicator;
import cn.com.gs.common.util.StringUtil;

import java.net.Socket;


public class SocketClientTest {

    public static void main(String[] args) throws Exception {
        // 1. 创建套接字，指定服务端Ip、Port
        Socket socket = new Socket("127.0.0.1", 9000);
        // 2. 向服务端发送消息，并等待回复
        BasicCommunicator communicator = new BasicCommunicator(socket);
        String message = "我是client";
        communicator.send(StringUtil.getBytes(message));

        byte[] recv = communicator.recv();
        System.out.println(StringUtil.getString(recv));

        socket.close();
    }
}

公共收发类

package cn.com.gs.common.socket;

import cn.com.gs.common.define.Constants;
import cn.com.gs.common.util.HexUtil;

import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.net.Socket;


public class BasicCommunicator {
    protected long maxRequestLength = Constants.LENGTH_5MB;
    protected long maxResponseLength = Constants.LENGTH_5MB;

    protected int READ_BLOCK_LENGTH = 1024; // 按块读

    public Socket socket;
    protected DataOutputStream out;
    protected DataInputStream input;

    
    public BasicCommunicator(Socket s) {
        socket = s;
        try {
            out = new DataOutputStream(socket.getOutputStream());
            input = new DataInputStream(socket.getInputStream());
        } catch (Exception e) {
        }
    }

    
    public void send(byte[] data) throws Exception {
        byte[] bs = HexUtil.int2Byte(data.length);
        byte[] sData = new byte[bs.length + data.length];

        System.arraycopy(bs, 0, sData, 0, bs.length);
        System.arraycopy(data, 0, sData, bs.length, data.length);
        out.write(sData);
        out.flush();
    }

    
    public int recvLength() throws Exception {
        int len = input.readInt();
        if ((len <= 0) || (len > maxRequestLength))
            throw new Exception("recv length is over limit, len is " + len);

        return len;
    }

    public byte[] recv() throws Exception {
        // 收到的报文长度
        int len = recvLength();

        byte[] allData = new byte[len];
        byte[] data = null;
        int rlen = len;

        while (rlen > 0) {
            if (rlen > READ_BLOCK_LENGTH)
                data = new byte[READ_BLOCK_LENGTH];
            else
                data = new byte[rlen];

            int alen = input.read(data);
            System.arraycopy(data, 0, allData, len - rlen, alen);
            rlen -= alen;
        }

        return allData;
    }

    public void close() {
        try {
            if (socket != null) {
                socket.close();
            }
        } catch (Exception e) {
        }
    }

}