SocketCloseDetection.java

import java.io.IOException;
import java.io.InputStream;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.concurrent.Semaphore;

public class SocketCloseDetection {
    public static void main(String[] args) throws IOException, InterruptedException {
        final ServerSocket serverSocket = new ServerSocket(6677);
        final Semaphore semaphore = new Semaphore(1);
        semaphore.acquire();
        new Thread(new Runnable() {
            @Override
            public void run() {
                try {
                    final Socket accept = serverSocket.accept();
                    semaphore.acquire();
                    System.out.println("closing server socket in 3 seconds...");
                    Thread.sleep(3000);
                    accept.close();
                    semaphore.release();
                } catch (IOException | InterruptedException e) {
                    throw new RuntimeException(e);
                }

            }
        }).start();
        Thread.sleep(100);

        System.out.println("client socket, wait until read...");
        final Socket socket = new Socket("localhost", serverSocket.getLocalPort());
        final InputStream inputStream = socket.getInputStream();
        semaphore.release();

        final int read = read(inputStream);
        socket.close(); // mark as closed

        System.out.println("inputStream.read=" + read);
        System.out.println("bound=" + socket.isBound());
        System.out.println("connected=" + socket.isConnected());
        System.out.println("closed=" + socket.isClosed());
        System.out.println("input shutdown=" + socket.isInputShutdown());
        System.out.println("output shutdown=" + socket.isOutputShutdown());

        Thread.sleep(5000);
    }

    public static int read(InputStream inputStream) throws IOException {
        try {
            return inputStream.read();
        } catch (Exception ignore) {
            ignore.printStackTrace();
            return -2;
        }
    }
}