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Java socket：如何防止java.net.BindException

[英]Java socket : how to prevent java.net.BindException

原文 2012-10-08 19:01:48 1 3 java/ sockets/ serversocket

I have implemented a LAN game and test on same computer by : create a class, create a server and a client in different thread in this class and connect together. 我已经在同一台计算机上实现了局域网游戏和测试：创建一个类，在这个类的不同线程中创建一个服务器和一个客户端并连接在一起。

After I close two windows (client and server) and I do above step again : run java class, create a server and a client. 关闭两个窗口（客户端和服务器）后，我再次执行上述步骤：运行java类，创建服务器和客户端。 I always meet this error : java.net.BindException (because this port has been created before and hasn't closed yet). 我总是遇到这个错误： java.net.BindException （因为此端口之前已创建，尚未关闭）。

Every time I create server socket, in catch, I always put serverSocket.close() . 每次我创建服务器套接字时，在catch中，我总是把serverSocket.close() 。 but that error still met with me. 但这个错误仍然遇到了我。 Please give me some ideas to prevent this. 请给我一些想法以防止这种情况发生。

@ : and if we know one port has been created, can we close it, and make new ones ? @：如果我们知道已经创建了一个端口，我们可以关闭它并创建新端口吗？

Thanks :) 谢谢：）

3 个解决方案

您应该将serverSocket.close（）放在finally块中，并且可能需要等待几秒钟才能再次尝试绑定到该地址。

Anything put in a catch block isn't run unless an Exception is caught. 除非捕获异常，否则不会运行任何放入catch块的内容。 Instead, put the close() call in a finally block to ensure it is always run. 相反，将close()调用放在finally块中以确保它始终运行。

After calling close() on channel could be not enough. 在通道上调用close()之后可能还不行。 See explanation here: http://hea-www.harvard.edu/~fine/Tech/addrinuse.html The TCP connection could stay in CLOSE-WAIT or TIME-WAIT state. 请参阅此处的说明： http ： //hea-www.harvard.edu/~fine/Tech/addrinuse.html TCP连接可以保持CLOSE-WAIT或TIME-WAIT状态。 You can play with reusing the address (SO_REUSEADDR), but it didn't work for me. 您可以重复使用地址（SO_REUSEADDR），但它对我不起作用。 The best is to wait exactly the timeout which is set for CLOSE-WAIT or TIME-WAIT on network level. 最好是等待在网络级别上为CLOSE-WAIT或TIME-WAIT设置的超时。