Here you can find the source of available(final int port)
private static boolean available(final int port)
//package com.java2s; /*//from w ww . j a v a 2s .c o m * [y] hybris Platform * * Copyright (c) 2000-2014 hybris AG * All rights reserved. * * This software is the confidential and proprietary information of hybris * ("Confidential Information"). You shall not disclose such Confidential * Information and shall use it only in accordance with the terms of the * license agreement you entered into with hybris. * * */ import java.io.IOException; import java.net.ServerSocket; public class Main { private static boolean available(final int port) { ServerSocket serverSocket = null; try { serverSocket = new ServerSocket(port); serverSocket.setReuseAddress(true); return true; } catch (final IOException e) { // } finally { if (serverSocket != null) { try { serverSocket.close(); } catch (final IOException e) { /* should not be thrown */ } } } return false; } }