ServerSocket类的常用方法
1.accept:侦听并接受此套接字的连接;此方法在连接传入之前一直阻塞。
2.setSoTimeout(timeout)方法的作用时设置超时时间,通过指定超时timeout值启用/禁用超时功能,以ms为单位。
必须在进入阻塞前调用这个方法,才能生效,一旦超时,程序会触发SocketTimeoutException异常;默认值是0即永远等待。
Server.java
package com.company.s7; import java.io.IOException; import java.net.ServerSocket; public class Server { public static void main(String[] args) { try { ServerSocket serverSocket=new ServerSocket(8000); System.out.println(serverSocket.getSoTimeout()); serverSocket.setSoTimeout(4000); System.out.println(serverSocket.getSoTimeout()); System.out.println(); System.out.println("begin "+System.currentTimeMillis()); serverSocket.accept(); System.out.println(" end "+System.currentTimeMillis()); }catch (IOException e){ e.printStackTrace(); } } }
Client.java
package com.company.s7; import java.io.IOException; import java.net.Socket; public class Client { public static void main(String[] args) { try { System.out.println("client begin "+System.currentTimeMillis()); Socket socket=new Socket("localhost",8000); System.out.println("client end "+System.currentTimeMillis()); }catch (IOException e){ e.printStackTrace(); System.out.println("catch "+System.currentTimeMillis()); } } }
backlog参数含义:
允许接受客户端连接请求的个数。
如果队列已满,则拒接该连接。
blacklog参数如果小于等于0,则使用默认值50;
Server.java
package com.company.s71; import javax.sound.midi.Soundbank; import java.io.IOException; import java.net.ServerSocket; import java.net.Socket; public class Server { public static void main(String[] args) throws IOException, InterruptedException { ServerSocket serverSocket=new ServerSocket(8088,3); //sleep(5000)的作用是不让ServerSocket调用accept()方法, //而是由客户端Socket先发奇10个连接请求 //然后在执行accept方法时只能接收3个连接 Thread.sleep(5000); System.out.println("accept1 begin"); Socket socket1=serverSocket.accept(); System.out.println("accept1 end"); System.out.println("accept2 begin"); Socket socket2=serverSocket.accept(); System.out.println("accept2 end"); System.out.println("accept3 begin"); Socket socket3=serverSocket.accept(); System.out.println("accept3 end"); System.out.println("accept4 begin"); Socket socket4=serverSocket.accept(); System.out.println("accept4 end"); System.out.println("accept5 begin"); Socket socket5=serverSocket.accept(); System.out.println("accept5 end"); socket1.close(); socket2.close(); socket3.close(); socket4.close(); socket5.close(); serverSocket.close(); } }
Client.java
package com.company.s71; import java.io.IOException; import java.net.Socket; public class Client { public static void main(String[] args) throws IOException { Socket socket1=new Socket("localhost",8088); Socket socket2=new Socket("localhost",8088); Socket socket3=new Socket("localhost",8088); Socket socket4=new Socket("localhost",8088); // Socket socket5=new Socket("localhost",8088); } }
先启动server.java,然后快速的启动client.java;
但是让我很奇怪的是服务端启动五秒之后,再启动客户端,反而能正确的执行;
如果由知道的人,请留言区告知,谢谢。