Interrupting ServerSocket Accept() Method
In Java, the ServerSocket class provides the accept() method to wait for incoming client connection requests. This method blocks until a client connects, potentially indefinitely. When designing a multithreaded server application, it is sometimes necessary to interrupt this blocking operation in response to external events.
Consider the scenario described in the question, where an "Admin" thread needs to shut down the server (including client threads) and the main thread. The blocking accept() call in the main thread prevents the server from responding to shutdown requests from the Admin thread.
To resolve this, the Java community recommends using the close() method to interrupt the accept() call. Here's how:
From a separate thread (in this case, the Admin thread), call the close() method on the ServerSocket object. This will cause the accept() call in the main thread to throw a SocketException.
In the main thread, within the while(listening) loop, handle the SocketException thrown by accept() to gracefully shut down the server and complete the shutdown process.
Here is a code snippet to illustrate this approach:
<code class="java">ServerSocket serverSocket = new ServerSocket(port); while (listening) { try { Socket clientSocket = serverSocket.accept(); // Handle client connection } catch (SocketException e) { // Shutdown the server and other threads listening = false; // Notify client threads to disconnect } }</code>
By using the close() method to interrupt the blocking accept() call, you can respond to external events and gracefully shut down the server.
The above is the detailed content of Here are a few question-based titles that capture the essence of the article: * How to Interrupt a Blocking ServerSocket `accept()` Method in Java? * Gracefully Shutting Down a Java Server: Interrupt. For more information, please follow other related articles on the PHP Chinese website!