Java tutorial
/* * (C) Copyright 2014 Nuxeo SAS (http://nuxeo.com/) and contributors. * * All rights reserved. This program and the accompanying materials * are made available under the terms of the GNU Lesser General Public License * (LGPL) version 2.1 which accompanies this distribution, and is available at * http://www.gnu.org/licenses/lgpl-2.1.html * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * Contributors: * Maxime Hilaire * */ package org.nuxeo.ecm.core.cache; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.nuxeo.runtime.model.ContributionFragmentRegistry; /** * Registry to register cache * * @since 6.0 */ public final class CacheRegistry extends ContributionFragmentRegistry<CacheDescriptor> { private static final Log log = LogFactory.getLog(CacheRegistry.class); // map of cache protected final Map<String, CacheDescriptor> caches = new HashMap<String, CacheDescriptor>(); @Override public String getContributionId(CacheDescriptor contrib) { return contrib.name; } @Override public void contributionUpdated(String id, CacheDescriptor descriptor, CacheDescriptor newOrigContrib) { String name = descriptor.name; if (name == null) { throw new RuntimeException("The cache name must not be null!"); } if (descriptor.remove) { contributionRemoved(id, descriptor); return; } if (caches.containsKey(name)) { throw new IllegalStateException( String.format("Another cache has already been registered for the given name %s", name)); } caches.put(name, descriptor); log.info("cache registered: " + name); } @Override public boolean isSupportingMerge() { return false; } @Override public void contributionRemoved(String id, CacheDescriptor origContrib) { String name = origContrib.name; CacheDescriptor cache = caches.remove(name); if (cache == null) { throw new IllegalStateException("No such cache registered" + name); } try { cache.stop(); } catch (RuntimeException e) { log.error(String.format("Error while removing cache '%s'", name), e); } log.info("cache removed: " + name); } @Override public CacheDescriptor clone(CacheDescriptor orig) { return orig.clone(); } @Override public void merge(CacheDescriptor src, CacheDescriptor dst) { boolean remove = src.remove; // keep old remove info: if old contribution was removed, new one // should replace the old one completely if (remove) { dst.remove = remove; // don't bother merging return; } } public CacheAttributesChecker getCache(String name) { if (caches.containsKey(name)) { return caches.get(name).cacheChecker; } return null; } public List<CacheAttributesChecker> getCaches() { List<CacheAttributesChecker> res = new ArrayList<CacheAttributesChecker>(caches.size()); for (CacheDescriptor desc : caches.values()) { res.add(desc.cacheChecker); } return res; } public void start() { RuntimeException errors = new RuntimeException("Cannot start caches, check suppressed error"); for (CacheDescriptor desc : caches.values()) { try { desc.start(); } catch (RuntimeException cause) { errors.addSuppressed(cause); } } if (errors.getSuppressed().length > 0) { throw errors; } } public void stop() { RuntimeException errors = new RuntimeException("Cannot stop caches, check suppressed error"); for (CacheDescriptor desc : caches.values()) { try { desc.stop(); } catch (RuntimeException cause) { errors.addSuppressed(cause); } } if (errors.getSuppressed().length > 0) { throw errors; } } }