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/* * $Id: CacheFilter.java,v 1.4 2008/11/05 16:39:28 laddi Exp $ * Created on 7.1.2005 * * Copyright (C) 2005 Idega Software hf. All Rights Reserved. * * This software is the proprietary information of Idega hf. * Use is subject to license terms. */ package com.idega.servlet.filter; import java.io.IOException; import javax.servlet.FilterChain; import javax.servlet.FilterConfig; import javax.servlet.ServletContext; import javax.servlet.ServletException; import javax.servlet.ServletRequest; import javax.servlet.ServletResponse; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import net.sf.ehcache.Cache; import net.sf.ehcache.CacheException; import net.sf.ehcache.CacheManager; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import com.idega.core.accesscontrol.business.LoginBusinessBean; import com.idega.core.cache.filter.SimplePageCachingFilter; import com.idega.idegaweb.IWMainApplication; /** * <p> * Filter that can be enabled to generically cache of output from all .jsps or Servlets.<br> * The rule is that this filter when enabled caches output of all GET requests when the user * is not authenticated into the idegaWeb user system. * </p> * Last modified: $Date: 2008/11/05 16:39:28 $ by $Author: laddi $ * * @author <a href="mailto:tryggvi@idega.com">Tryggvi Larusson</a> * @version $Revision: 1.4 $ */ public class CacheFilter extends SimplePageCachingFilter { private static final Log log = LogFactory.getLog(CacheFilter.class.getName()); public static final int DEFAULT_CACHE_SIZE = 1000; public static final long DEFAULT_CACHE_TIME_SECONDS = 60 * 20; public static final long DEFAULT_CACHE_TIME_IDLE_SECONDS = 60 * 20; public static final String DEFAULT_CACHE_NAME = "CacheFilter"; public static boolean defaultEnabled = false; private static final String METHOD_GET = "GET"; public static final String PROPERTY_CACHE_FILTER_ENABLED = "CACHE_FILTER_ENABLED"; public static final String PROPERTY_CACHE_FILTER_SIZE = "CACHE_FILTER_SIZE"; public static final String PROPERTY_CACHE_FILTER_TTL = "CACHE_FILTER_TTL"; public static final String PROPERTY_CACHE_FILTER_IDLE_TTL = "CACHE_FILTER_IDLE_TTL"; private static boolean INITALIZED = false; /* * (non-Javadoc) * * @see net.sf.ehcache.constructs.web.filter.CachingFilter#doFilter(javax.servlet.http.HttpServletRequest, * javax.servlet.http.HttpServletResponse, javax.servlet.FilterChain) */ @Override public void doFilter(ServletRequest sRequest, ServletResponse sResponse, FilterChain chain) throws ServletException { HttpServletRequest request = (HttpServletRequest) sRequest; HttpServletResponse response = (HttpServletResponse) sResponse; if (cacheRequest(request, response)) { super.doFilter(sRequest, sResponse, chain); } else { try { chain.doFilter(sRequest, sResponse); } catch (IOException e) { throw new ServletException(e); } } } /** * Initialises blockingCache to use * * @throws CacheException The most likely cause is that a cache has not been * configured in ehcache's configuration file ehcache.xml for the filter name */ @Override public void doInit() throws CacheException { //overriding from superclass int cacheSize = DEFAULT_CACHE_SIZE; long cacheTTLSeconds = DEFAULT_CACHE_TIME_SECONDS; long cacheTTLIdleSeconds = DEFAULT_CACHE_TIME_IDLE_SECONDS; FilterConfig config = this.getFilterConfig(); ServletContext context = config.getServletContext(); IWMainApplication iwma = IWMainApplication.getIWMainApplication(context); try { String propEnabled = iwma.getSettings().getProperty(PROPERTY_CACHE_FILTER_ENABLED); defaultEnabled = Boolean.valueOf(propEnabled).booleanValue(); if (defaultEnabled) { log.info("CacheFilter is enabled"); } else { log.info("CacheFilter is disabled"); } } catch (Exception e) { } try { String propCacheSize = iwma.getSettings().getProperty(PROPERTY_CACHE_FILTER_SIZE); cacheSize = Integer.parseInt(propCacheSize); } catch (Exception e) { } try { String propTTL = iwma.getSettings().getProperty(PROPERTY_CACHE_FILTER_TTL); cacheTTLSeconds = Long.parseLong(propTTL); } catch (Exception e) { } try { String propIdleTTL = iwma.getSettings().getProperty(PROPERTY_CACHE_FILTER_IDLE_TTL); cacheTTLIdleSeconds = Long.parseLong(propIdleTTL); } catch (Exception e) { } final String cacheName = getCacheName(); CacheManager cm = CacheManager.create(); cm.removeCache(cacheName); Cache cache = new Cache(cacheName, cacheSize, true, false, cacheTTLSeconds, cacheTTLIdleSeconds); cm.addCache(cache); super.doInit(); INITALIZED = true; } protected void checkInitialization() { if (!INITALIZED) { try { synchronized (this) { if (!INITALIZED) { doInit(); } } } catch (CacheException e) { // TODO Auto-generated catch block e.printStackTrace(); } } } /** * <p> * Tells the CacheFilter to reload its settings. * </p> */ public static void reload() { INITALIZED = false; } /** * <p> * TODO tryggvil describe method cacheRequest * </p> * @param request * @param response * @return */ protected boolean cacheRequest(HttpServletRequest request, HttpServletResponse response) { checkInitialization(); if (defaultEnabled) { String method = request.getMethod(); if (method.equals(METHOD_GET)) { LoginBusinessBean loginBusiness = LoginBusinessBean.getLoginBusinessBean(request); if (loginBusiness.isLoggedOn(request)) { //Never cache for a logged on user: return false; } return true; } } return false; } /* * (non-Javadoc) * * @see net.sf.ehcache.constructs.web.filter.CachingFilter#getCacheName() */ @Override protected String getCacheName() { return DEFAULT_CACHE_NAME; } /* * (non-Javadoc) * * @see net.sf.ehcache.constructs.web.filter.CachingFilter#calculateKey(javax.servlet.http.HttpServletRequest) */ @Override protected String calculateKey(HttpServletRequest request) { return super.calculateKey(request); } }