Java tutorial
/* * Copyright (c) 2011-2013 Flite, Inc * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN * THE SOFTWARE. */ package org.flite.cach3.aop; import net.spy.memcached.*; import org.aspectj.lang.*; import org.aspectj.lang.annotation.*; import org.flite.cach3.annotations.*; import org.flite.cach3.annotations.groups.InvalidateAssignCaches; import org.flite.cach3.api.*; import org.slf4j.*; import org.springframework.core.*; import org.springframework.core.annotation.*; import java.lang.reflect.*; import java.security.*; import java.util.*; @Aspect @Order(Ordered.HIGHEST_PRECEDENCE / 2) public class InvalidateAssignCacheAdvice extends CacheBase { private static final Logger LOG = LoggerFactory.getLogger(InvalidateAssignCacheAdvice.class); @Pointcut("@annotation(org.flite.cach3.annotations.InvalidateAssignCache)") public void invalidateAssign() { } @AfterReturning(pointcut = "invalidateAssign()", returning = "retVal") public Object cacheInvalidateAssign(final JoinPoint jp, final Object retVal) throws Throwable { try { doInvalidate(jp, retVal); } catch (Throwable ex) { if (LOG.isDebugEnabled()) { LOG.warn("Caching on " + jp.toShortString() + " aborted due to an error.", ex); } else { LOG.warn("Caching on " + jp.toShortString() + " aborted due to an error: " + ex.getMessage()); } } return retVal; } @Pointcut("@annotation(org.flite.cach3.annotations.groups.InvalidateAssignCaches)") public void invalidateAssigns() { } @AfterReturning(pointcut = "invalidateAssigns()", returning = "retVal") public Object cacheInvalidateAssigns(final JoinPoint jp, final Object retVal) throws Throwable { try { doInvalidate(jp, retVal); } catch (Throwable ex) { if (LOG.isDebugEnabled()) { LOG.warn("Caching on " + jp.toShortString() + " aborted due to an error.", ex); } else { LOG.warn("Caching on " + jp.toShortString() + " aborted due to an error: " + ex.getMessage()); } } return retVal; } private void doInvalidate(final JoinPoint jp, final Object retVal) throws Throwable { if (isCacheDisabled()) { LOG.debug("Caching is disabled."); return; } final MemcachedClientIF cache = getMemcachedClient(); final Method methodToCache = getMethodToCache(jp); List<InvalidateAssignCache> lAnnotations; if (methodToCache.getAnnotation(InvalidateAssignCache.class) != null) { lAnnotations = Arrays.asList(methodToCache.getAnnotation(InvalidateAssignCache.class)); } else { lAnnotations = Arrays.asList(methodToCache.getAnnotation(InvalidateAssignCaches.class).value()); } for (int i = 0; i < lAnnotations.size(); i++) { // This is injected caching. If anything goes wrong in the caching, LOG the crap outta it, // but do not let it surface up past the AOP injection itself. try { final AnnotationInfo info = getAnnotationInfo(lAnnotations.get(i), methodToCache.getName()); final String cacheKey = buildCacheKey(info.getAsString(AType.ASSIGN_KEY), info.getAsString(AType.NAMESPACE), info.getAsString(AType.KEY_PREFIX)); if (cacheKey == null || cacheKey.trim().length() == 0) { throw new InvalidParameterException("Unable to find a cache key"); } cache.delete(cacheKey); // Notify the observers that a cache interaction happened. final List<InvalidateAssignCacheListener> listeners = getPertinentListeners( InvalidateAssignCacheListener.class, info.getAsString(AType.NAMESPACE)); if (listeners != null && !listeners.isEmpty()) { for (final InvalidateAssignCacheListener listener : listeners) { try { listener.triggeredInvalidateAssignCache(info.getAsString(AType.NAMESPACE), info.getAsString(AType.ASSIGN_KEY), retVal, jp.getArgs()); } catch (Exception ex) { LOG.warn("Problem when triggering a listener.", ex); } } } } catch (Throwable ex) { if (LOG.isDebugEnabled()) { LOG.warn("Caching on " + jp.toShortString() + " aborted due to an error.", ex); } else { LOG.warn("Caching on " + jp.toShortString() + " aborted due to an error: " + ex.getMessage()); } } } } /*default*/ static AnnotationInfo getAnnotationInfo(final InvalidateAssignCache annotation, final String targetMethodName) { final AnnotationInfo result = new AnnotationInfo(); if (annotation == null) { throw new InvalidParameterException( String.format("No annotation of type [%s] found.", InvalidateAssignCache.class.getName())); } final String namespace = annotation.namespace(); if (AnnotationConstants.DEFAULT_STRING.equals(namespace) || namespace == null || namespace.length() < 1) { throw new InvalidParameterException( String.format("Namespace for annotation [%s] must be defined on [%s]", InvalidateAssignCache.class.getName(), targetMethodName)); } result.add(new AType.Namespace(namespace)); final String assignKey = annotation.assignedKey(); if (AnnotationConstants.DEFAULT_STRING.equals(assignKey) || assignKey == null || assignKey.length() < 1) { throw new InvalidParameterException( String.format("AssignedKey for annotation [%s] must be defined on [%s]", InvalidateAssignCache.class.getName(), targetMethodName)); } result.add(new AType.AssignKey(assignKey)); return result; } }