001    /**
002     * Copyright (c) 2000-2013 Liferay, Inc. All rights reserved.
003     *
004     * This library is free software; you can redistribute it and/or modify it under
005     * the terms of the GNU Lesser General Public License as published by the Free
006     * Software Foundation; either version 2.1 of the License, or (at your option)
007     * any later version.
008     *
009     * This library is distributed in the hope that it will be useful, but WITHOUT
010     * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
011     * FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
012     * details.
013     */
014    
015    package com.liferay.portal.kernel.servlet;
016    
017    import com.liferay.portal.kernel.util.ServerDetector;
018    
019    import javax.servlet.jsp.JspFactory;
020    
021    /**
022     * @author Shuyang Zhou
023     */
024    public class JspFactorySwapper {
025    
026            public static void swap() {
027                    if (!ServerDetector.isTomcat()) {
028                            return;
029                    }
030    
031                    JspFactory jspFactory = JspFactory.getDefaultFactory();
032    
033                    if (jspFactory instanceof JspFactoryWrapper) {
034                            return;
035                    }
036    
037                    synchronized (JspFactorySwapper.class) {
038                            if (_jspFactoryWrapper == null) {
039                                    _jspFactoryWrapper = new JspFactoryWrapper(jspFactory);
040                            }
041    
042                            JspFactory.setDefaultFactory(_jspFactoryWrapper);
043                    }
044            }
045    
046            private static JspFactoryWrapper _jspFactoryWrapper;
047    
048    }