TestSocketAccept.java

import java.nio.channels.*;
import java.net.*;
import java.lang.management.*;
import com.sun.management.UnixOperatingSystemMXBean;
import java.net.BindException;

public class TestSocketAccept {
  public static void main(String[] args) throws Exception {

    OperatingSystemMXBean os = ManagementFactory.getOperatingSystemMXBean();
    UnixOperatingSystemMXBean nix = (UnixOperatingSystemMXBean)os;

    for (int offset=0; offset < 64000; offset++){
      ServerSocketChannel serverSocketChannel = ServerSocketChannel.open();
      serverSocketChannel.configureBlocking(false);
      try {
        serverSocketChannel.socket().bind(new InetSocketAddress("::1", 1080+offset));
        SocketChannel socketChannel = serverSocketChannel.accept();
      } catch (BindException e) {
        // skip
      }
      System.out.println("count: " + nix.getOpenFileDescriptorCount());
    }
  }
}