1. 例子1：客户端发送信息给服务端，服务端将数据显式在控制台上
    2. public class TCPtest1{
    3.     //客户端
    4.     @Test
    5.     public void client(){
    6.         Socket socket = null;
    7.         OutputStream os = null;
    8.         try {
    9.             //1.创建Socket对象，指明服务端的ip和端口号
    10.             InetAddress inet = InetAddress.getByName("127.0.0.1");
    11.             socket = new Socket(inet, 8899);
    12.             //2.获取一个输出流，用于输出数据
    13.             os = socket.getOutputStream();
    14.             os.write("你好我是客户端MM".getBytes());
    15.             //3.写出数据的操作
    16.             os.close();
    17.         } catch (IOException e) {
    18.             e.printStackTrace();
    19.         } finally {
    20.             //4.资源的关闭
    21.             if (os != null) {
    22.                 try {
    23.                     os.close();
    24.                 } catch (IOException e) {
    25.                     e.printStackTrace();
    26.                 }
    27.             }
    28.             if (socket != null){
    29.                 try {
    30.                     socket.close();
    31.                 } catch (IOException e) {
    32.                     e.printStackTrace();
    33.                 }
    34.             }
    35.         }
    36.     }
    37.     //服务端
    38.     @Test
    39.     public void server(){
    40.         ServerSocket ss = null;
    41.         Socket socket = null;
    42.         InputStream is = null;
    43.         ByteArrayOutputStream baos = null;
    44.         try {
    45.             //1.创建服务器端的SeverSocket，指明自己的端口号
    46.             ss = new ServerSocket(8899);
    47.             //2.调用accept()表明接收来自于客户端的socket
    48.             socket = ss.accept();
    49.             //3.读取输入流当中的数据
    50.             is = socket.getInputStream();
    51.             //不建议这样写，可能有乱码
    52. //        byte[] buffer = new byte[1024];
    53. //        int len;
    54. //        while ((len = is.read(buffer)) != -1){
    55. //            String str = new String(buffer, 0 ,len);
    56. //            System.out.println(str);
    57. //        }
    58.             baos = new ByteArrayOutputStream();
    59.             byte[] buffer = new byte[5];
    60.             int len;
    61.             while ((len = is.read(buffer)) != -1){
    62.                 baos.write(buffer,0,len);
    63.             }
    64.             System.out.println(baos.toString());
    65.         } catch (IOException e) {
    66.             e.printStackTrace();
    67.         } finally {
    68.             //5.关闭资源
    69.             if (is != null){
    70.                 try {
    71.                     is.close();
    72.                 } catch (IOException e) {
    73.                     e.printStackTrace();
    74.                 }
    75.             }
    76.             if (baos != null){
    77.                 try {
    78.                     baos.close();
    79.                 } catch (IOException e) {
    80.                     e.printStackTrace();
    81.                 }
    82.             }
    83.             if (socket != null){
    84.                 try {
    85.                     socket.close();
    86.                 } catch (IOException e) {
    87.                     e.printStackTrace();
    88.                 }
    89.             }
    90.             if (ss != null){
    91.                 try {
    92.                     ss.close();
    93.                 } catch (IOException e) {
    94.                     e.printStackTrace();
    95.                 }
    96.             }
    97.         }
    98.     }
    99. }