Java 网络编程（五）TCP

客户端

　　1.连接服务器socket

　　2.发送消息

//客户端
public class TcpClientDemo01 {
    public static void main(String[] args) {
        Socket socket = null;
        OutputStream os = null;
        try {
            //1.要知道服务器的地址,端口号
            InetAddress serverIp = InetAddress.getByName("127.0.0.1");
            int port = 9999;
            //2.创建一个socket连接
            socket = new Socket(serverIp,port);
            //3.发送消息 IO流
            os = socket.getOutputStream();
            os.write("你好，欢迎您！".getBytes());
        } catch (Exception e) {
            e.printStackTrace();
        }finally {
            if (os!=null){
                try {
                    os.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            if (socket != null){
                try {
                    socket.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }

    }
}

服务器

　　1.建立服务端口ServerSocket

　　2.等待用户的连接accept

　　3.接受用户的消息

//服务端
public class TcpServerDemo01 {
    public static void main(String[] args) {
        ServerSocket serverSocket = null;
        Socket accept = null;
        InputStream is = null;
        ByteArrayOutputStream baos = null;
        try {
            //1.我得有一个地址
            serverSocket = new ServerSocket(9999);
            //2.等待客户端连接过来
            accept = serverSocket.accept();
            //3.读取客户端的消息
            is = accept.getInputStream();
            //管道流
            baos = new ByteArrayOutputStream();
            byte[] buffer = new byte[1024];
            int len;
            while((len = is.read(buffer)) != -1){
                baos.write(buffer,0,len);
            }
            System.out.println(baos.toString());
        } catch (IOException e) {
            e.printStackTrace();
        }finally {
            //关闭资源
            if(baos != null) {
                try {
                    baos.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            if (is != null) {
                try {
                    is.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            if (accept != null) {
                try {
                    accept.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            if (serverSocket != null) {
                try {
                    serverSocket.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }

    }
}

文件上传

客户端

public class TcpClientDemo02 {
    public static void main(String[] args) throws Exception{
        //1.创建一个Socket连接
        Socket socket = new Socket(InetAddress.getByName("127.0.0.1"), 9000);
        //2.创建一个输出流
        OutputStream os = socket.getOutputStream();
        //3.读取文件
        FileInputStream fis = new FileInputStream(new File("a.jpg"));
        //4.写出文件
        byte[] buffer = new byte[1024];
        int len;
        while((len=fis.read(buffer))!=-1){
            os.write(buffer,0,len);
        }
        //通知服务器我已经结束了
        socket.shutdownOutput();//我已经传输完了
        
        //确定服务器接收完毕才能够断开连接
        InputStream inputStream = socket.getInputStream();
        ByteArrayOutputStream baos = new ByteArrayOutputStream();
       byte[] buffer2 = new byte[1024];
       int len2;
       while((len2 = inputStream.read(buffer2)) != -1){
           baos.write(buffer2,0,len2);
       }

        System.out.println(baos.toString());

        //5.关闭资源
        baos.close();
       inputStream.close();
        fis.close();
        os.close();
        socket.close();
    }
}

　　服务端

public class TcpServerDemo02 {
    public static void main(String[] args) throws Exception{
        //1.创建服务
        ServerSocket serverSocket = new ServerSocket(9000);
        //2.监听客户端的连接
        Socket socket = serverSocket.accept();//阻塞式监听，会一直等待客户端连接
        //3.获取输入流
        InputStream is = socket.getInputStream();
        //4.文件输出
        FileOutputStream fos = new FileOutputStream(new File("receive.jpg"));
        byte[] buffer = new byte[1024];
        int len ;
        while ((len = is.read(buffer)) != -1){
            fos.write(buffer,0,len);
        }
        //通知客户端接收完毕
        OutputStream os = socket.getOutputStream();
        os.write("我接收完毕，你可以断开了".getBytes());

        //关闭资源
        fos.close();
        is.close();
        socket.close();
        serverSocket.close();
    }
}

Tomcat

服务端

　　·自定义S

　　·Tomcat服务器S

客户端

　　·自定义C

　　·浏览器B