TCP字节流编程

客户端连接服务端具体过程 

package com.socket;
import java.io.IOException;
import java.net.ServerSocket;
import java.net.Socket;
public class SocketTCP01Server {
    public static void main(String[] args) throws IOException {
        //1.在本机的9999端口监听，要求：在本机的其他服务没有监听9999端口
        ServerSocket serverSocket = new ServerSocket(9999);
        System.out.println("服务器端，在9999端口监听，等待连接。。。");
        //2.当没有客户端连接9999端口，程序会阻塞，等待连接
        //如果有客户端连接，会返回一个socket对象
        Socket socket = serverSocket.accept();
        System.out.println("socket="+socket.getClass());

    }
}

服务端执行，控制台显示

客户端一旦执行，结果如下：

package com.socket;
import java.io.IOException;
import java.net.InetAddress;
import java.net.Socket;
public class SocketTCP01Client {
    public static void main(String[] args) throws IOException {
        //1.连接服务器端
        //连接本机的9999端口，如果连接成功，返回Socket对象
        Socket socket = new Socket(InetAddress.getLocalHost(), 9999);
        System.out.println("客户端返回socket="+socket.getClass());
        //2.连接上后，生成socket
        //3.输出流 将数据写入数据通道
    }
}

 接下来看具体实现

package com.socket;
import java.io.IOException;
import java.io.InputStream;
import java.net.ServerSocket;
import java.net.Socket;
public class SocketTCP01Server {
    public static void main(String[] args) throws IOException {
        //1.在本机的9999端口监听，要求：在本机的其他服务没有监听9999端口
        ServerSocket serverSocket = new ServerSocket(9999);
        System.out.println("服务端，在9999端口监听，等待连接。。。");
        //2.当没有客户端连接9999端口，程序会阻塞，等待连接
        //如果有客户端连接，会返回一个socket对象
        //ServerSocket 可以通过accept() 返回多个socket[多个客户端连接服务端的并发]
        Socket socket = serverSocket.accept();
        System.out.println("服务端socket=" + socket.getClass());
        //3.通过输入流 读取客户端写入到数据通道的数据
        InputStream inputStream = socket.getInputStream();
        //4.IO读取
        byte[] b = new byte[1024];
        int readLength = 0;
        while ((readLength = inputStream.read(b)) != -1) {
            //根据读取到的实际长度，显示内容
            System.out.println(new String(b, 0, readLength));
        }
        //5.关闭流和socket
        inputStream.close();
        socket.close();
        serverSocket.close();
    }
}

package com.socket;
import java.io.IOException;
import java.io.OutputStream;
import java.net.InetAddress;
import java.net.Socket;
public class SocketTCP01Client {
    public static void main(String[] args) throws IOException {
        //1.连接服务器端
        //连接本机的9999端口，如果连接成功，返回Socket对象
        Socket socket = new Socket(InetAddress.getLocalHost(), 9999);
        System.out.println("客户端返回socket="+socket.getClass());
        //2.连接上后，生成socket
        OutputStream outputStream = socket.getOutputStream();
        //3.输出流 将数据写入数据通道
        outputStream.write("hello,Server!".getBytes());
        //4.关闭流对象和socket
        outputStream.close();
        socket.close();
        System.out.println("客户端退出");
    }
}

 

对客户端连接服务端优化

package com.socket;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.ServerSocket;
import java.net.Socket;
public class SocketTCP02Server {
    public static void main(String[] args) throws IOException {
        //1.在本机的9999端口监听，要求：在本机的其他服务没有监听9999端口
        ServerSocket serverSocket = new ServerSocket(9999);
        System.out.println("服务端，在9999端口监听，等待连接。。。");
        //2.当没有客户端连接9999端口，程序会阻塞，等待连接
        //如果有客户端连接，会返回一个socket对象
        //ServerSocket 可以通过accept() 返回多个socket[多个客户端连接服务端的并发]
        Socket socket = serverSocket.accept();
        System.out.println("服务端socket=" + socket.getClass());
        //3.获取socket关联的输入流 读取客户端写入到数据通道的数据
        InputStream inputStream = socket.getInputStream();
        //4.IO读取
        byte[] b = new byte[1024];
        int readLength = 0;
        while ((readLength = inputStream.read(b)) != -1) {
            //根据读取到的实际长度，显示内容
            System.out.println(new String(b, 0, readLength));
        }
        //5.获取socket关联的输出流 将数据写入数据通道
        OutputStream outputStream = socket.getOutputStream();
        outputStream.write("hello,Client".getBytes());
        //设置结束标记
        socket.shutdownOutput();
        //6.关闭流和socket
        outputStream.close();
        inputStream.close();
        socket.close();
        serverSocket.close();
    }
}

package com.socket;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.InetAddress;
import java.net.Socket;
public class SocketTCP02Client {
    public static void main(String[] args) throws IOException {
        //1.连接服务器端
        //连接本机的9999端口，如果连接成功，返回Socket对象
        Socket socket = new Socket(InetAddress.getLocalHost(), 9999);
        System.out.println("客户端返回socket="+socket.getClass());
        //2.连接上后，生成socket
        OutputStream outputStream = socket.getOutputStream();
        //3.获取socket关联的输出流 将数据写入数据通道
        outputStream.write("hello,Server!".getBytes());
        //设置结束标记
        socket.shutdownOutput();
        //4.获取socket关联的输入流 读取服务端写入到数据通道的数据
        InputStream inputStream = socket.getInputStream();
        byte[] buf=new byte[1024];
        int readLength=0;
        while ((readLength=inputStream.read(buf))!=-1){
            System.out.println(new String(buf,0,readLength));
        }
        //5.关闭流对象和socket
        inputStream.close();
        outputStream.close();
        socket.close();
        System.out.println("客户端退出");
    }
}

 跟开头代码相比，增加了上面内容，必须牢记添加输出流写完数据后，需要添加socket.shutdownOutput();