我正在用java编写一个网络服务器，我有一个小问题。让代码说话：
import java.io.IOException;
import java.net.ServerSocket;
/**
* Another flavor of the server module.
* According to GOD (also known as Joshua Bloch) this is the proper
* implementation of a singleton (Note: serialization).
*
* @author estol
*/
public enum EnumSingletonServer implements ServerInterface, Runnable
{
SERVER;
private ServerSocket serverSocket = null;
private boolean Listening = true;
@Override
public void bind() {
this.bind(DEFAULTPORT);
}
@Override
public void bind(int Port) {
try {
this.serverSocket = new ServerSocket(Port);
} catch (IOException ioe) {
System.err.printf("Cannot bind to port %d\nAdditional information:\n%s\nExiting\n", Port, ioe.getMessage());
System.exit(1);
}
}
/**
* Not that elegant, but does not work with flipping the switch, because
* the loop (in public void run()) is only running when there is an incoming connection(?).
*
*
* FIXME
*/
@Override
public void shutdown() {
// this.Listening = !this.Listening; // FIXME
System.exit(0);
}
/**
* Accepting connections on the port, we are bound to.
* The main loop of the server is a bit broken. Does not exit,
* if we flip the value of this.Listening, but exit on the next incoming
* connection. This is a problem.
*
* FIXME
*/
@Override
public void run() {
try {
System.out.printf("Listening on %d\n", this.serverSocket.getLocalPort());
Thread.currentThread().setName("ServerThread");
// FIXME
do {
new Thread(new ServerWorkerThreads(this.serverSocket.accept(), 3)).start();
} while (this.Listening);
this.serverSocket.close();
System.exit(0);
} catch (IOException ioe) {
System.err.printf("Cannot accept on, or close port %d\nAdditional information:\n%s\nExiting\n", this.serverSocket.getLocalPort(), ioe.getMessage());
System.exit(1);
}
}
}
现在，正如评论中所说，如果我否定/翻转/更改变量 this.Listening 的值，循环不会停止，而是在下一个连接时退出。
起初我没有在枚举器中实现服务器，我用一个类来实现，它在被序列化后未能成为单例，但它按照我的预期执行。我尝试了 while (condition) done，以及 do while(condition) 循环。
所有帮助将不胜感激。