网络编程TCP

/*
 * 
 * 客户端发送信息给服务端，接收后并打印在控制台上，同时发送已收到信息给客户端
 */

//客户端
class client1 implements Runnable {
	public void run() {
		Socket socket = null;
		OutputStream os = null;
		InputStream is = null;
		try {
			socket = new Socket(InetAddress.getByName("127.0.0.1"), 8989);
			os = socket.getOutputStream();
			os.write("我是客户端1！！".getBytes());
			// shutdownOutput()：执行此方法显示的告诉服务端发送完毕
			socket.shutdownOutput();
			is = socket.getInputStream();
			byte[] b = new byte[40];
			int len;
			while ((len = is.read(b)) != -1) {
				String str = new String(b, 0, len);
				System.out.println(str);
			}
		} catch (UnknownHostException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		} finally {
			if (is != null) {
				try {
					is.close();
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
			if (os != null) {
				try {
					os.close();
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
			if (socket != null) {
				try {
					socket.close();
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
		}

	}
}

//服务端
class server1 implements Runnable {
	public void run() {
		ServerSocket ss = null;
		Socket s = null;
		InputStream is = null;
		OutputStream os = null;
		try {
			ss = new ServerSocket(8989);
			s = ss.accept();
			is = s.getInputStream();
			byte[] b = new byte[40];
			int len;
			while ((len = is.read(b)) != -1) {
				String str = new String(b, 0, len);
				//服务端接收并打印
				System.out.println("客户端发来: " + str);
			}
			os = s.getOutputStream();
			os.write("我是服务端：我已收到!".getBytes());
		} catch (IOException e) {
			e.printStackTrace();
		} finally {
			if (os != null) {
				try {
					os.close();
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
			if (is != null) {
				try {
					is.close();
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
			if (s != null) {
				try {
					s.close();
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
			if (ss != null) {
				try {
					ss.close();
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
		}
	}
}

public class TestTCP2 {
	public static void main(String[] args) {
		new Thread(new server1()).start();
		new Thread(new client1()).start();
	}
}