| /******************************************************************************* |
| * Copyright (c) 2010 IBM Corporation and others. |
| * All rights reserved. This program and the accompanying materials |
| * are made available under the terms of the Eclipse Public License v1.0 |
| * which accompanies this distribution, and is available at |
| * http://www.eclipse.org/legal/epl-v10.html |
| * |
| * Contributors: |
| * IBM Corporation - initial API and implementation |
| *******************************************************************************/ |
| package org.eclipse.wst.jsdt.debug.core.jsdi.connect; |
| |
| |
| import java.io.IOException; |
| import java.net.ServerSocket; |
| |
| import org.eclipse.wst.jsdt.debug.internal.core.JavaScriptDebugPlugin; |
| |
| /** |
| * Utility class to find a port to debug on. |
| * |
| * @since 1.0 |
| * @noinstantiate This class is not intended to be instantiated by clients. |
| */ |
| public final class SocketUtil { |
| |
| /** |
| * Constructor |
| * No instantiation |
| */ |
| private SocketUtil() {} |
| |
| /** |
| * Returns a free port number on localhost, or -1 if unable to find a free port. |
| * |
| * @return a free port number on localhost, or -1 if unable to find a free port |
| */ |
| public static int findFreePort() { |
| ServerSocket socket = null; |
| try { |
| socket = new ServerSocket(0); |
| return socket.getLocalPort(); |
| } |
| catch (IOException e) { |
| JavaScriptDebugPlugin.log(e); |
| } |
| finally { |
| if (socket != null) { |
| try { |
| socket.close(); |
| } |
| catch (IOException e) { |
| JavaScriptDebugPlugin.log(e); |
| } |
| } |
| } |
| return -1; |
| } |
| |
| /** |
| * Returns a free port number encoded as a string |
| * |
| * @return a free port number encoded as a string |
| */ |
| public static String findFreePortString() { |
| return Integer.toString(findFreePort()); |
| } |
| } |