/**
* The contents of this file are subject to the license and copyright
* detailed in the LICENSE and NOTICE files at the root of the source
* tree and available online at
*
* http://www.dspace.org/license/
*/
package org.dspace.services.caching;
import java.io.IOException;
import java.io.InputStream;
import java.io.Serializable;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
import net.sf.ehcache.CacheManager;
import net.sf.ehcache.Ehcache;
import net.sf.ehcache.Statistics;
import org.dspace.kernel.ServiceManager;
import org.dspace.kernel.mixins.ConfigChangeListener;
import org.dspace.kernel.mixins.InitializedService;
import org.dspace.kernel.mixins.ServiceChangeListener;
import org.dspace.kernel.mixins.ShutdownService;
import org.dspace.providers.CacheProvider;
import org.dspace.services.CachingService;
import org.dspace.services.ConfigurationService;
import org.dspace.services.RequestService;
import org.dspace.services.caching.model.EhcacheCache;
import org.dspace.services.caching.model.MapCache;
import org.dspace.services.model.*;
import org.dspace.services.model.CacheConfig.CacheScope;
import org.dspace.utils.servicemanager.ProviderHolder;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Required;
/**
* Implementation of the core caching service, which is available for
* anyone who is writing code for DSpace to use.
*
* @author Aaron Zeckoski (azeckoski @ gmail.com)
*/
public final class CachingServiceImpl implements CachingService, InitializedService, ShutdownService, ConfigChangeListener, ServiceChangeListener {
private static Logger log = LoggerFactory.getLogger(CachingServiceImpl.class);
/**
* This is the event key for a full cache reset.
*/
protected static final String EVENT_RESET = "caching.reset";
/**
* The default config location.
*/
protected static final String DEFAULT_CONFIG = "org/dspace/services/caching/ehcache-config.xml";
/**
* All the non-thread caches that we know about.
* Mostly used for tracking purposes.
*/
private Map<String, EhcacheCache> cacheRecord = new ConcurrentHashMap<String, EhcacheCache>();
/**
* All the request caches. This is bound to the thread.
* The initial value of this TL is set automatically when it is
* created.
*/
private Map<String, Map<String, MapCache>> requestCachesMap = new ConcurrentHashMap<String, Map<String, MapCache>>();
/**
* @return the current request map which is bound to the current thread
*/
protected Map<String, MapCache> getRequestCaches() {
if (requestService == null || requestService.getCurrentRequestId() == null ) {
return null;
}
Map<String, MapCache> requestCaches = requestCachesMap.get(requestService.getCurrentRequestId());
if (requestCaches == null) {
requestCaches = new HashMap<String, MapCache>();
requestCachesMap.put(requestService.getCurrentRequestId(), requestCaches);
}
return requestCaches;
}
/**
* Unbinds all request caches. Destroys the caches completely.
*/
public void unbindRequestCaches() {
if (requestService != null) {
requestCachesMap.remove(requestService.getCurrentRequestId());
}
}
private ConfigurationService configurationService;
@Autowired
@Required
public void setConfigurationService(ConfigurationService configurationService) {
this.configurationService = configurationService;
}
private RequestService requestService;
@Autowired
public void setRequestService(RequestService requestService) {
this.requestService = requestService;
}
private ServiceManager serviceManager;
@Autowired
@Required
public void setServiceManager(ServiceManager serviceManager) {
this.serviceManager = serviceManager;
}
/** The underlying cache manager; injected. */
protected net.sf.ehcache.CacheManager cacheManager;
@Autowired
@Required
public void setCacheManager(net.sf.ehcache.CacheManager cacheManager) {
this.cacheManager = cacheManager;
}
public net.sf.ehcache.CacheManager getCacheManager() {
return cacheManager;
}
private boolean useClustering = false;
private boolean useDiskStore = true;
private int maxElementsInMemory = 2000;
private int timeToLiveSecs = 3600;
private int timeToIdleSecs = 600;
/**
* Reloads the config settings from the configuration service.
*/
protected void reloadConfig() {
useClustering = configurationService.getPropertyAsType(knownConfigNames[0], boolean.class);
useDiskStore = configurationService.getPropertyAsType(knownConfigNames[1], boolean.class);
maxElementsInMemory = configurationService.getPropertyAsType(knownConfigNames[2], int.class);
timeToLiveSecs = configurationService.getPropertyAsType(knownConfigNames[3], int.class);
timeToIdleSecs = configurationService.getPropertyAsType(knownConfigNames[4], int.class);
}
/**
* WARNING: Do not change the order of these! <br/>
* If you do, you have to fix the {@link #reloadConfig()} method -AZ
*/
private String[] knownConfigNames = {
"caching.use.clustering", // bool - whether to use clustering
"caching.default.use.disk.store", // whether to use the disk store
"caching.default.max.elements", // the maximum number of elements in memory, before they are evicted
"caching.default.time.to.live.secs", // the default amount of time to live for an element from its creation date
"caching.default.time.to.idle.secs", // the default amount of time to live for an element from its last accessed or modified date
};
/* (non-Javadoc)
* @see org.dspace.kernel.mixins.ConfigChangeListener#notifyForConfigNames()
*/
public String[] notifyForConfigNames() {
return knownConfigNames == null ? null : knownConfigNames.clone();
}
/* (non-Javadoc)
* @see org.dspace.kernel.mixins.ConfigChangeListener#configurationChanged(java.util.List, java.util.Map)
*/
public void configurationChanged(List<String> changedSettingNames, Map<String, String> changedSettings) {
reloadConfig();
}
/**
* This will make it easier to handle a provider which might go away
* because the classloader is gone.
*/
private ProviderHolder<CacheProvider> provider = new ProviderHolder<CacheProvider>();
public CacheProvider getCacheProvider() {
return provider.getProvider();
}
private void reloadProvider() {
boolean current = (getCacheProvider() != null);
CacheProvider cacheProvider = serviceManager.getServiceByName(CacheProvider.class.getName(), CacheProvider.class);
provider.setProvider(cacheProvider);
if (cacheProvider != null) {
log.info("Cache Provider loaded: " + cacheProvider.getClass().getName());
} else {
if (current) {
log.info("Cache Provider unloaded");
}
}
}
/* (non-Javadoc)
* @see org.dspace.kernel.mixins.ServiceChangeListener#notifyForTypes()
*/
public Class<?>[] notifyForTypes() {
return new Class<?>[] { CacheProvider.class };
}
/* (non-Javadoc)
* @see org.dspace.kernel.mixins.ServiceChangeListener#serviceRegistered(java.lang.String, java.lang.Object, java.util.List)
*/
public void serviceRegistered(String serviceName, Object service, List<Class<?>> implementedTypes) {
provider.setProvider((CacheProvider) service);
}
/* (non-Javadoc)
* @see org.dspace.kernel.mixins.ServiceChangeListener#serviceUnregistered(java.lang.String, java.lang.Object)
*/
public void serviceUnregistered(String serviceName, Object service) {
provider.setProvider(null);
}
/* (non-Javadoc)
* @see org.dspace.kernel.mixins.InitializedService#init()
*/
public void init() {
log.info("init()");
// get settings
reloadConfig();
// don't display the EhCache update notice in logs - it's meant for developers, not users
System.setProperty("net.sf.ehcache.skipUpdateCheck", "true");
// make sure we have a cache manager
if (cacheManager == null) {
// not injected so we need to create one
ClassLoader cl = Thread.currentThread().getContextClassLoader();
InputStream is = cl.getResourceAsStream(DEFAULT_CONFIG);
try {
if (is == null) {
throw new IllegalStateException("Could not init the cache manager, no config file found as a resource in the classloader: " + DEFAULT_CONFIG);
}
cacheManager = new CacheManager(is);
} finally {
if (is != null) {
try {
is.close();
} catch (IOException e) {
log.debug("Error closing config stream", e);
}
}
}
}
// get all caches out of the cachemanager and load them into the cache list
List<Ehcache> ehcaches = getAllEhCaches(false);
for (Ehcache ehcache : ehcaches) {
EhcacheCache cache = new EhcacheCache(ehcache, null);
cacheRecord.put(cache.getName(), cache);
}
// load provider
reloadProvider();
if (requestService != null) {
requestService.registerRequestInterceptor(new CachingServiceRequestInterceptor());
}
log.info("Caching service initialized:\n" + getStatus(null));
}
/* (non-Javadoc)
* @see org.dspace.kernel.mixins.ShutdownService#shutdown()
*/
public void shutdown() {
log.info("destroy()");
// for some reason this causes lots of errors so not using it for now -AZ
//ehCacheManagementService.dispose();
try {
if (cacheRecord != null) {
cacheRecord.clear();
}
} catch (RuntimeException e) {
// whatever
}
try {
requestCachesMap.clear();
} catch (RuntimeException e) {
// whatever
}
try {
cacheManager.removalAll();
} catch (RuntimeException e) {
// whatever
}
try {
cacheManager.shutdown();
} catch (RuntimeException e) {
// whatever
}
}
/* (non-Javadoc)
* @see org.dspace.services.CachingService#destroyCache(java.lang.String)
*/
public void destroyCache(String cacheName) {
if (cacheName == null || "".equals(cacheName)) {
throw new IllegalArgumentException("cacheName cannot be null or empty string");
}
// handle provider first
if (getCacheProvider() != null) {
try {
getCacheProvider().destroyCache(cacheName);
} catch (Exception e) {
log.warn("Failure in provider ("+getCacheProvider()+"): " + e.getMessage());
}
}
EhcacheCache cache = cacheRecord.get(cacheName);
if (cache != null) {
cacheManager.removeCache(cacheName);
cacheRecord.remove(cacheName);
} else {
Map<String, MapCache> caches = getRequestCaches();
if (caches != null) {
caches.remove(cacheName);
}
}
}
/* (non-Javadoc)
* @see org.dspace.services.CachingService#getCache(java.lang.String, org.dspace.services.model.CacheConfig)
*/
public Cache getCache(String cacheName, CacheConfig cacheConfig) {
Cache cache = null;
if (cacheName == null || "".equals(cacheName)) {
throw new IllegalArgumentException("cacheName cannot be null or empty string");
}
if (cacheConfig != null && CacheScope.REQUEST.equals(cacheConfig.getCacheScope()) ) {
Map<String, MapCache> caches = getRequestCaches();
if (caches != null) {
cache = caches.get(cacheName);
}
if (cache == null) {
cache = instantiateMapCache(cacheName, cacheConfig);
}
} else {
// find the cache in the records if possible
cache = this.cacheRecord.get(cacheName);
// handle provider
if (cache == null && getCacheProvider() != null) {
try {
cache = getCacheProvider().getCache(cacheName, cacheConfig);
} catch (Exception e) {
log.warn("Failure in provider ("+getCacheProvider()+"): " + e.getMessage());
}
}
if (cache == null) {
cache = instantiateEhCache(cacheName, cacheConfig);
}
}
return cache;
}
/* (non-Javadoc)
* @see org.dspace.services.CachingService#getCaches()
*/
public List<Cache> getCaches() {
List<Cache> caches = new ArrayList<Cache>(this.cacheRecord.values());
if (getCacheProvider() != null) {
try {
caches.addAll( getCacheProvider().getCaches() );
} catch (Exception e) {
log.warn("Failure in provider ("+getCacheProvider()+"): " + e.getMessage());
}
}
// TODO implement reporting on request caches?
// caches.addAll(this.requestMap.values());
Collections.sort(caches, new NameComparator());
return caches;
}
/* (non-Javadoc)
* @see org.dspace.services.CachingService#getStatus(java.lang.String)
*/
public String getStatus(String cacheName) {
final StringBuilder sb = new StringBuilder();
if (cacheName == null || "".equals(cacheName)) {
// add in overall memory stats
sb.append("** Memory report\n");
sb.append(" freeMemory: ").append(Runtime.getRuntime().freeMemory());
sb.append("\n");
sb.append(" totalMemory: ").append(Runtime.getRuntime().totalMemory());
sb.append("\n");
sb.append(" maxMemory: ").append(Runtime.getRuntime().maxMemory());
sb.append("\n");
// caches summary report
List<Cache> allCaches = getCaches();
sb.append("\n** Full report of all known caches (").append(allCaches.size()).append("):\n");
for (Cache cache : allCaches) {
sb.append(" * ");
sb.append(cache.toString());
sb.append("\n");
if (cache instanceof EhcacheCache) {
Ehcache ehcache = ((EhcacheCache)cache).getCache();
sb.append(generateCacheStats(ehcache));
sb.append("\n");
}
}
} else {
// report for a single cache
sb.append("\n** Report for cache (").append(cacheName).append("):\n");
Cache cache = this.cacheRecord.get(cacheName);
if (cache == null) {
Map<String, MapCache> caches = getRequestCaches();
if (caches != null) {
cache = caches.get(cacheName);
}
}
if (cache == null) {
sb.append(" * Could not find cache by this name: ").append(cacheName);
} else {
sb.append(" * ");
sb.append(cache.toString());
sb.append("\n");
if (cache instanceof EhcacheCache) {
Ehcache ehcache = ((EhcacheCache)cache).getCache();
sb.append(generateCacheStats(ehcache));
sb.append("\n");
}
}
}
return sb.toString();
}
/* (non-Javadoc)
* @see org.dspace.services.CachingService#resetCaches()
*/
public void resetCaches() {
log.debug("resetCaches()");
List<Cache> allCaches = getCaches();
for (Cache cache : allCaches) {
cache.clear();
}
if (getCacheProvider() != null) {
try {
getCacheProvider().resetCaches();
} catch (Exception e) {
log.warn("Failure in provider ("+getCacheProvider()+"): " + e.getMessage());
}
}
System.runFinalization(); // force the JVM to try to clean up any remaining objects
// DO NOT CALL System.gc() here or I will have you shot -AZ
log.info("doReset(): Memory Recovery to: " + Runtime.getRuntime().freeMemory());
}
/**
* Return all caches from the CacheManager.
*
* @param sorted if true then sort by name
* @return the list of all known ehcaches
*/
protected List<Ehcache> getAllEhCaches(boolean sorted) {
log.debug("getAllCaches()");
final String[] cacheNames = cacheManager.getCacheNames();
if (sorted) {
Arrays.sort(cacheNames);
}
final List<Ehcache> caches = new ArrayList<Ehcache>(cacheNames.length);
for (String cacheName : cacheNames) {
caches.add(cacheManager.getEhcache(cacheName));
}
return caches;
}
/**
* Create an EhcacheCache (and the associated EhCache) using the
* supplied name (with default settings), or get the cache out of
* Spring or the current configured cache.
* <p>
* This expects that the cacheRecord has already been checked and
* will not check it again.
* <p>
* Will proceed in this order:
* <ol>
* <li>Attempt to load a bean with the name of the cache</li>
* <li>Attempt to load cache from caching system</li>
* <li>Create a new cache by this name</li>
* <li>Put the cache in the cache record</li>
* </ol>
*
* @param cacheName the name of the cache
* @param cacheConfig the config for this cache
* @return a cache instance
*/
protected EhcacheCache instantiateEhCache(String cacheName, CacheConfig cacheConfig) {
if (log.isDebugEnabled()) {
log.debug("instantiateEhCache(String " + cacheName + ")");
}
if (cacheName == null || "".equals(cacheName)) {
throw new IllegalArgumentException("String cacheName must not be null or empty!");
}
// try to locate a named cache in the service manager
Ehcache ehcache = serviceManager.getServiceByName(cacheName, Ehcache.class);
// try to locate the cache in the cacheManager by name
if (ehcache == null) {
// if this cache name is created or already in use then we just get it
if (!cacheManager.cacheExists(cacheName)) {
// did not find the cache
if (cacheConfig == null) {
cacheManager.addCache(cacheName); // create a new cache using ehcache defaults
} else {
if (useClustering) {
// TODO
throw new UnsupportedOperationException("Still need to do this");
} else {
cacheManager.addCache(cacheName); // create a new cache using ehcache defaults
}
}
log.info("Created new Cache (from default settings): " + cacheName);
}
ehcache = cacheManager.getEhcache(cacheName);
}
// wrap the ehcache in the cache impl
EhcacheCache cache = new EhcacheCache(ehcache, cacheConfig);
cacheRecord.put(cacheName, cache);
return cache;
}
/**
* Create a thread map cache using the supplied name with supplied
* settings.
* <p>
* This expects that the cacheRecord has already been checked and
* will not check it again. It also places the cache into the
* request map.
*
* @param cacheName the name of the cache
* @param cacheConfig the config for this cache
* @return a cache instance
*/
protected MapCache instantiateMapCache(String cacheName, CacheConfig cacheConfig) {
if (log.isDebugEnabled()) {
log.debug("instantiateMapCache(String " + cacheName + ")");
}
if (cacheName == null || "".equals(cacheName)) {
throw new IllegalArgumentException("String cacheName must not be null or empty!");
}
// check for existing cache
MapCache cache = null;
CacheScope scope = CacheScope.REQUEST;
if (cacheConfig != null) {
scope = cacheConfig.getCacheScope();
}
Map<String, MapCache> caches = getRequestCaches();
if (caches != null) {
if (CacheScope.REQUEST.equals(scope)) {
cache = caches.get(cacheName);
}
if (cache == null) {
cache = new MapCache(cacheName, cacheConfig);
// place cache into the right TL
if (CacheScope.REQUEST.equals(scope)) {
caches.put(cacheName, cache);
}
}
}
return cache;
}
/**
* Generate some stats for this cache.
* Note that this is not cheap so do not use it very often.
*
* @param cache an Ehcache
* @return the stats of this cache as a string
*/
protected static String generateCacheStats(Ehcache cache) {
StringBuilder sb = new StringBuilder();
sb.append(cache.getName()).append(":");
// this will make this costly but it is important to get accurate settings
cache.setStatisticsAccuracy(Statistics.STATISTICS_ACCURACY_GUARANTEED);
Statistics stats = cache.getStatistics();
final long memSize = cache.getMemoryStoreSize();
final long diskSize = cache.getDiskStoreSize();
final long size = memSize + diskSize;
final long hits = stats.getCacheHits();
final long misses = stats.getCacheMisses();
final String hitPercentage = ((hits+misses) > 0) ? ((100l * hits) / (hits + misses)) + "%" : "N/A";
final String missPercentage = ((hits+misses) > 0) ? ((100l * misses) / (hits + misses)) + "%" : "N/A";
sb.append(" Size: ").append(size).append(" [memory:").append(memSize).append(", disk:").append(diskSize).append("]");
sb.append(", Hits: ").append(hits).append(" [memory:").append(stats.getInMemoryHits()).append(", disk:").append(stats.getOnDiskHits()).append("] (").append(hitPercentage).append(")");
sb.append(", Misses: ").append(misses).append(" (").append(missPercentage).append(")");
return sb.toString();
}
/**
* Compare two Cache objects by name.
*/
public static final class NameComparator implements Comparator<Cache>, Serializable {
public static final long serialVersionUID = 1l;
public int compare(Cache o1, Cache o2) {
return o1.getName().compareTo(o2.getName());
}
}
private class CachingServiceRequestInterceptor implements RequestInterceptor {
public void onStart(String requestId, Session session) {
if (requestId != null) {
Map<String, MapCache> requestCaches = requestCachesMap.get(requestId);
if (requestCaches == null) {
requestCaches = new HashMap<String, MapCache>();
requestCachesMap.put(requestId, requestCaches);
}
}
}
public void onEnd(String requestId, Session session, boolean succeeded, Exception failure) {
if (requestId != null) {
requestCachesMap.remove(requestId);
}
}
public int getOrder() {
return 1;
}
}
}