|
1
24 package org.riotfamily.cachius.spring;
25
26 import javax.servlet.http.HttpServletRequest  ;
27 import javax.servlet.http.HttpServletResponse ;
28
29 import org.apache.commons.logging.Log;
30 import org.apache.commons.logging.LogFactory;
31 import org.riotfamily.cachius.Cache;
32 import org.riotfamily.cachius.CacheItem;
33 import org.riotfamily.cachius.CachiusResponseWrapper;
34 import org.riotfamily.cachius.ItemUpdater;
35 import org.riotfamily.cachius.support.SessionUtils;
36 import org.riotfamily.common.web.view.ViewResolverHelper;
37 import org.springframework.beans.factory.DisposableBean;
38 import org.springframework.context.ApplicationContext;
39 import org.springframework.context.ApplicationContextAware;
40 import org.springframework.core.Ordered;
41 import org.springframework.web.servlet.HandlerAdapter;
42 import org.springframework.web.servlet.ModelAndView;
43 import org.springframework.web.servlet.View;
44 import org.springframework.web.servlet.mvc.LastModified;
45
46
62 public class CacheableControllerHandlerAdapter implements HandlerAdapter,
63 DisposableBean, ApplicationContextAware, Ordered {
64
65 private Log log = LogFactory.getLog(CacheableControllerHandlerAdapter.class);
66
67 private Cache cache;
68
69 private ViewResolverHelper viewResolverHelper;
70
71 private int order = 0;
72
73 private boolean enabled = true;
74
75 public CacheableControllerHandlerAdapter(Cache cache) {
76 this.cache = cache;
77 }
78
79
85 public void setEnabled(boolean enabled) {
86 this.enabled = enabled;
87 }
88
89
92 public int getOrder() {
93 return this.order;
94 }
95
96
99 public void setOrder(int order) {
100 this.order = order;
101 }
102
103 public void setApplicationContext(ApplicationContext context) {
104 viewResolverHelper = new ViewResolverHelper(context);
105 }
106
107
111 public void destroy() {
112 cache.persist();
113 }
114
115
119 public boolean supports(Object handler) {
120 return enabled && handler instanceof CacheableController;
121 }
122
123
129 public ModelAndView handle(HttpServletRequest request,
130 HttpServletResponse response, Object handler) throws Exception {
131
132 CacheableController controller = (CacheableController) handler;
133 String cacheKey = controller.getCacheKey(request);
134 CacheItem cacheItem = getCacheItem(cacheKey, request);
135 if (cacheItem == null) {
136 log.debug("No cacheItem - Response won't be cached");
137 return controller.handleRequest(request, response);
138 }
139
140 if (isUpToDate(cacheItem, controller, request)) {
141 cacheItem.writeTo(request, response);
142 return null;
143 }
144 else {
145 return handleRequestAndUpdateCacheItem(request, response,
146 controller, cacheItem);
147 }
148 }
149
150 protected ModelAndView handleRequestAndUpdateCacheItem(
151 HttpServletRequest request, HttpServletResponse response,
152 CacheableController controller, CacheItem cacheItem)
153 throws Exception {
154
155 ItemUpdater update = new ItemUpdater(cacheItem, request);
156 CachiusResponseWrapper wrapper = new CachiusResponseWrapper(
157 response, update);
158
159 ModelAndView mv = controller.handleRequest(request, wrapper);
160 if (mv == null) {
161 wrapper.flushBuffer();
162 update.updateCacheItem();
163 return null;
164 }
165 else {
166 View view = viewResolverHelper.resolveView(request, mv);
167 View cachingView = new CachingView(view, wrapper, update);
168 return new ModelAndView(cachingView, mv.getModel());
169 }
170 }
171
172 protected CacheItem getCacheItem(String cacheKey,
173 HttpServletRequest request) {
174
175 if (cacheKey == null) {
176 log.debug("Cache key is null - Response won't be cached.");
177 return null;
178 }
179
180 boolean encodedUrls = SessionUtils.urlsNeedEncoding(request);
181 if (encodedUrls) {
182 cacheKey += ";jsessionid";
183 }
184
185 log.debug("Getting cache item for key " + cacheKey);
186 CacheItem cacheItem = cache.getItem(cacheKey);
187 if (cacheItem == null) {
188 log.warn("Failed to create cache item");
189 }
190 else if (cacheItem.isNew() || !cacheItem.exists()) {
191 cacheItem.setFilterSessionId(encodedUrls);
192 }
193 return cacheItem;
194 }
195
196
207 protected boolean isUpToDate(CacheItem cacheItem,
208 CacheableController controller, HttpServletRequest request)
209 throws Exception {
210
211 if (cacheItem.isNew() || !cacheItem.exists()) {
214 log.debug("Item is new or has been invalidated");
215 return false;
216 }
217
218 long now = System.currentTimeMillis();
219 long ttl = controller.getTimeToLive();
220 if (ttl == CacheableController.CACHE_ETERNALLY) {
221 log.debug("Item is cached eternally");
222 return true;
223 }
224 if (cacheItem.getLastCheck() + ttl < now) {
225 long mtime = controller.getLastModified(request);
226 log.debug("Last modified: " + mtime);
227 cacheItem.setLastCheck(now);
228 if (mtime > cacheItem.getLastModified()) {
229 cacheItem.setLastModified(now);
233 return false;
234 }
235 }
236 else if (log.isDebugEnabled()) {
237 log.debug("Item not expired yet, will live for another " +
238 (ttl - (now - cacheItem.getLastCheck())) + " ms.");
239 }
240 return true;
241 }
242
243
246 public long getLastModified(HttpServletRequest request, Object handler) {
247 if (handler instanceof LastModified) {
248 CacheableController controller = (CacheableController) handler;
249 String cacheKey = controller.getCacheKey(request);
250 CacheItem cacheItem = getCacheItem(cacheKey, request);
251 if (cacheItem != null) {
252 if (!cacheItem.isNew()) {
253 long now = System.currentTimeMillis();
254 long ttl = controller.getTimeToLive();
255 if (ttl == CacheableController.CACHE_ETERNALLY
256 || cacheItem.getLastCheck() + ttl <= now) {
257
258 return cacheItem.getLastModified();
259 }
260 }
261 try {
262 return controller.getLastModified(request);
263 }
264 catch (Exception e) {
265 log.error("Error invoking the last-modified method", e);
266 }
267 }
268 }
269 return -1L;
270 }
271
272 } |
Popular Tags |
Java API By Example, From Geeks To Geeks.