001    /**
002     * Copyright (c) 2000-2010 Liferay, Inc. All rights reserved.
003     *
004     * The contents of this file are subject to the terms of the Liferay Enterprise
005     * Subscription License ("License"). You may not use this file except in
006     * compliance with the License. You can obtain a copy of the License by
007     * contacting Liferay, Inc. See the License for the specific language governing
008     * permissions and limitations under the License, including but not limited to
009     * distribution rights of the Software.
010     *
011     *
012     *
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    }