diff --git a/src/java/com/whirlycott/cache/CacheDecorator.java b/src/java/com/whirlycott/cache/CacheDecorator.java index 33fa6ca..ec69e64 100644 --- a/src/java/com/whirlycott/cache/CacheDecorator.java +++ b/src/java/com/whirlycott/cache/CacheDecorator.java @@ -1,13 +1,13 @@ /* Copyright 2004 Philip Jacob Seth Fitzsimmons - + Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at - + http://www.apache.org/licenses/LICENSE-2.0 - + Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. @@ -34,7 +34,7 @@ * Owns the cache tuning thread and provides housekeeping facilities for * ManagedCache implementations. One CacheDecorator is created for each Cache * named in the whirlycache.xml configuration file. - * + * * @author Phil Jacob */ public class CacheDecorator implements Runnable, Cache { @@ -86,16 +86,16 @@ public class CacheDecorator implements Runnable, Cache { /** * Constructor for a CacheDecorator. - * + * * @param _managedCache * @param _configuration * @param policies */ public CacheDecorator(final ManagedCache _managedCache, final CacheConfiguration _configuration, final CacheMaintenancePolicy[] policies) { - name = _configuration.getName(); + this.name = _configuration.getName(); - if (null == name) { + if (null == this.name) { throw new IllegalArgumentException(Messages.getString("CacheDecorator.cache_config_cannot_be_null")); //$NON-NLS-1$ } @@ -111,24 +111,24 @@ public CacheDecorator(final ManagedCache _managedCache, final CacheConfiguration throw new IllegalArgumentException(Messages.getString("CacheDecorator.must_provide_single_policy")); //$NON-NLS-1$ } - policy = policies[0]; + this.policy = policies[0]; // Adaptive size plus the buffer (to prevent // ArrayIndexOutOfBoundsExceptions)s - adaptiveResults = new int[adaptiveMemorySize + adaptiveMemorySizeOverflow]; + this.adaptiveResults = new int[this.adaptiveMemorySize + this.adaptiveMemorySizeOverflow]; // This is the cache which we are managing. - managedCache = _managedCache; + this.managedCache = _managedCache; // Do some configuration. configure(_configuration); // Start up the management thread. - tunerThread = new Thread(this); - final Object[] args = { name }; - tunerThread.setName(Messages.getCompoundString("CacheDecorator.whirlycache_tuner", args)); //$NON-NLS-1$ - tunerThread.setDaemon(true); - tunerThread.start(); + this.tunerThread = new Thread(this); + final Object[] args = { this.name }; + this.tunerThread.setName(Messages.getCompoundString("CacheDecorator.whirlycache_tuner", args)); //$NON-NLS-1$ + this.tunerThread.setDaemon(true); + this.tunerThread.start(); } /** @@ -136,8 +136,8 @@ public CacheDecorator(final ManagedCache _managedCache, final CacheConfiguration */ public void clear() { log.info(Messages.getString("CacheDecorator.clearing_cache")); //$NON-NLS-1$ - managedCache.clear(); - Arrays.fill(adaptiveResults, 0); + this.managedCache.clear(); + Arrays.fill(this.adaptiveResults, 0); } /** @@ -155,20 +155,20 @@ protected void configure(final CacheConfiguration configuration) { * Looks at the last 'n' queries to determine whether the Cache should turn * on optimizations for a mostly-read environment (if the underlying * implementation of ManagedCache supports this). - * + * * @param _value * varies depending on whether this was a read, write, or * removal. */ protected void doAdaptiveAccounting(final int _value) { // We only care about the last 'n' adaptiveResults. - final int currentCounter = adaptiveResultCounter; - if (currentCounter >= adaptiveMemorySize) { - adaptiveResultCounter = 0; - adaptiveResults[0] = _value; + final int currentCounter = this.adaptiveResultCounter; + if (currentCounter >= this.adaptiveMemorySize) { + this.adaptiveResultCounter = 0; + this.adaptiveResults[0] = _value; } else { - adaptiveResults[currentCounter] = _value; - adaptiveResultCounter++; + this.adaptiveResults[currentCounter] = _value; + this.adaptiveResultCounter++; } } @@ -176,17 +176,17 @@ protected void doAdaptiveAccounting(final int _value) { * @return Returns the adaptiveMemorySize. */ protected int getAdaptiveMemorySize() { - return adaptiveMemorySize; + return this.adaptiveMemorySize; } /** * Calculates the adaptive hit rate for this cache. - * + * * @return adaptive hit ratio. */ public float getAdaptiveRatio() { - final int copy[] = new int[adaptiveMemorySize]; - System.arraycopy(adaptiveResults, 0, copy, 0, adaptiveMemorySize); + final int copy[] = new int[this.adaptiveMemorySize]; + System.arraycopy(this.adaptiveResults, 0, copy, 0, this.adaptiveMemorySize); int positives = 0; for (final int element : copy) { if (element == 1) { @@ -195,57 +195,79 @@ public float getAdaptiveRatio() { } // log.info("Positives: " + positives + "; Total: " + // adaptiveMemorySize); - return new Float(positives).floatValue() / new Float(adaptiveMemorySize).floatValue(); + return new Float(positives).floatValue() / new Float(this.adaptiveMemorySize).floatValue(); } /** * Returns an efficiency report string for this cache. - * + * * @return efficiency report for this cache. */ public String getEfficiencyReport() { - final Object[] args = { new Integer(managedCache.size()), new Long(recordKeeper.getTotalOperations()), new Long(recordKeeper.getHits()), new Float(getAdaptiveRatio()), + final Object[] args = { new Integer(this.managedCache.size()), new Long(this.recordKeeper.getTotalOperations()), new Long(this.recordKeeper.getHits()), new Float(getAdaptiveRatio()), new Float(getTotalHitrate()) }; return Messages.getCompoundString("CacheDecorator.efficiency_report", args); //$NON-NLS-1$ } + /** + * @return The total number of hits + */ + public long getHits() { + return recordKeeper.getHits(); + } + + + /** + * @return The total number of misses + */ + public long getMisses() { + return recordKeeper.getMisses(); + } + + /** + * @return The total number of operations on the cache + */ + public long getTotalOperations() { + return this.recordKeeper.getTotalOperations(); + } + /** * Get the maximum size of the cache. - * + * * @return Returns the maxSize. */ protected int getMaxSize() { - return maxSize; + return this.maxSize; } /** * @return Returns the policy in use for managing this cache. */ protected CacheMaintenancePolicy getPolicy() { - return policy; + return this.policy; } /** * @return Returns the sleepTime. */ protected long getSleepTime() { - return sleepTime; + return this.sleepTime; } /** * Returns the total hitrate since this Cache was started. - * + * * @return Total hitrate. */ - protected float getTotalHitrate() { - return new Long(recordKeeper.getHits()).floatValue() / new Long(recordKeeper.getTotalOperations()).floatValue(); + public float getTotalHitrate() { + return Long.valueOf(this.recordKeeper.getHits()).floatValue() / Long.valueOf(this.recordKeeper.getTotalOperations()).floatValue(); } /* * (non-Javadoc) - * + * * @see com.whirlycott.cache.Cache#remove(com.whirlycott.cache.Cacheable) */ public Object remove(final Cacheable _key) { @@ -256,7 +278,7 @@ public Object remove(final Cacheable _key) { /** * Removes an Object from the Cache and returns the removed Object. - * + * * @param _key * key associated with object to remove. */ @@ -266,17 +288,17 @@ public Object remove(final Object _key) { /** * An internal remove operation. - * + * * @param _key * @return the object that was removed */ protected Object internalRemove(final Object _key) { if (Constants.BUILD_STATS_ENABLED) { - recordKeeper.incrementTotalOperations(); + this.recordKeeper.incrementTotalOperations(); } if (_key != null) { - final Item cachedItem = (Item) managedCache.remove(_key); + final Item cachedItem = (Item) this.managedCache.remove(_key); // The compiler will optimize this. if (Constants.BUILD_STATS_ENABLED) { @@ -291,7 +313,7 @@ protected Object internalRemove(final Object _key) { /* * (non-Javadoc) - * + * * @see com.whirlycott.cache.Cache#retrieve(com.whirlycott.cache.Cacheable) */ public Object retrieve(final Cacheable _key) { @@ -306,28 +328,34 @@ protected Object internalRetrieve(final Object _key) { doAdaptiveAccounting(1); // Increment the number of totalQuestions. - recordKeeper.incrementTotalOperations(); + this.recordKeeper.incrementTotalOperations(); } // Set up the return value - final Item cachedItem = (Item) managedCache.get(_key); + final Item cachedItem = (Item) this.managedCache.get(_key); if (cachedItem != null) { // Bump the numbers. if (Constants.BUILD_STATS_ENABLED) { - cachedItem.setUsed(recordKeeper.getTotalOperations()); + cachedItem.setUsed(this.recordKeeper.getTotalOperations()); cachedItem.incrementCount(); } // Increment the adaptive algorithm and the hitcounter. final Object retval = cachedItem.getItem(); - if (retval != null && Constants.BUILD_STATS_ENABLED) { - recordKeeper.incrementHits(); + if (Constants.BUILD_STATS_ENABLED) { + if (retval != null) { + this.recordKeeper.incrementHits(); + } else { + this.recordKeeper.incrementMisses(); + } } return retval; } else { - + if (Constants.BUILD_STATS_ENABLED) { + this.recordKeeper.incrementMisses(); + } // Found nothing inside the cache. return null; } @@ -349,14 +377,14 @@ public void run() { final Thread t = Thread.currentThread(); try { - while (tunerThread == t) { + while (this.tunerThread == t) { // updates the cache's notion of the "current time" if (Constants.ITEM_EXPIRATION_ENABLED) { - currentTime = System.currentTimeMillis(); + this.currentTime = System.currentTimeMillis(); } if (Constants.BUILD_STATS_ENABLED) { - recordKeeper.startTuneCycle(); + this.recordKeeper.startTuneCycle(); // Adapt to mostly read or mostly write. tuneCache(); @@ -369,19 +397,19 @@ public void run() { } // Perform tuning and maintenance. - policy.performMaintenance(); + this.policy.performMaintenance(); try { // Sleep for a bit - Thread.sleep(sleepTime); + Thread.sleep(this.sleepTime); } catch (final InterruptedException e) { log.info(Messages.getString("CacheDecorator.tuning_thread_interrupted")); //$NON-NLS-1$ } if (Constants.BUILD_STATS_ENABLED) { - if (sleepTime > 0L) { - recordKeeper.calculateQueriesPerSecond(sleepTime); + if (this.sleepTime > 0L) { + this.recordKeeper.calculateQueriesPerSecond(this.sleepTime); } logStatistics(); @@ -400,11 +428,11 @@ public void run() { /** * Log some cache usage data depending on some conditions. - * + * */ protected void logStatistics() { - if (sleepTime > 0L && log.isDebugEnabled()) { - final Object[] args = { new Long(recordKeeper.getQueriesPerSecond()) }; + if (this.sleepTime > 0L && log.isDebugEnabled()) { + final Object[] args = { new Long(this.recordKeeper.getQueriesPerSecond()) }; log.debug(Messages.getCompoundString("CacheDecorator.query_rate", args)); //$NON-NLS-1$ } @@ -424,12 +452,12 @@ protected void setAdaptiveMemorySize(final int adaptiveMemorySize) { /** * Specify the ManagedCache that this Decorator owns. - * + * * @param cache * The ManagedCache to set. */ protected void setManagedCache(final ManagedCache cache) { - managedCache = cache; + this.managedCache = cache; log.debug(Messages.getString("CacheDecorator.managing_cache_with_type") + cache.getClass()); //$NON-NLS-1$ } @@ -444,16 +472,16 @@ protected void setMaxSize(final int maxSize) { /** * Tells the underlying ManagedCache implementation to turn on optimizations * for a mostly-read environment (if supported). - * + * * @param _mostlyRead * whether most operations are expected to be reads. */ public void setMostlyRead(final boolean _mostlyRead) { if (Constants.BUILD_STATS_ENABLED) { - recordKeeper.incrementTotalOperations(); + this.recordKeeper.incrementTotalOperations(); } - managedCache.setMostlyRead(_mostlyRead); + this.managedCache.setMostlyRead(_mostlyRead); } /** @@ -467,34 +495,43 @@ protected void setSleepTime(final long sleepTime) { /** Shut down this cache. */ public void shutdown() { if (log.isDebugEnabled()) { - log.debug(Messages.getString("CacheDecorator.shutting_down_cache") + name); //$NON-NLS-1$ + log.debug(Messages.getString("CacheDecorator.shutting_down_cache") + this.name); //$NON-NLS-1$ } if (Constants.BUILD_STATS_ENABLED) { log.info(getEfficiencyReport()); - recordKeeper.reset(); + this.recordKeeper.reset(); } - final Thread tunerThreadToKill = tunerThread; - tunerThread = null; + final Thread tunerThreadToKill = this.tunerThread; + this.tunerThread = null; tunerThreadToKill.interrupt(); } /** * Returns the number of items in the Cache. - * + * * @return number of items in the cache. */ public int size() { if (Constants.BUILD_STATS_ENABLED) { - recordKeeper.incrementTotalOperations(); + this.recordKeeper.incrementTotalOperations(); } - return managedCache.size(); + return this.managedCache.size(); + } + + /** + * Returns the number of items in the Cache. + * + * @return number of items in the cache. + */ + public int getSize() { + return size(); } /* * (non-Javadoc) - * + * * @see com.whirlycott.cache.Cache#store(com.whirlycott.cache.Cacheable, * java.lang.Object) */ @@ -505,7 +542,7 @@ public void store(final Cacheable key, final Object value) { /* * (non-Javadoc) - * + * * @see com.whirlycott.cache.Cache#store(com.whirlycott.cache.Cacheable, * java.lang.Object, long) */ @@ -523,7 +560,7 @@ public void store(final Object _key, final Object _value) { /* * (non-Javadoc) - * + * * @see com.whirlycott.cache.Cache#store(java.lang.Object, java.lang.Object, * long) */ @@ -533,7 +570,7 @@ public void store(final Object _key, final Object _value, final long _expiresAft /** * All stores go through this. - * + * * @param _key * @param _value * @param _expiresAfter @@ -541,12 +578,12 @@ public void store(final Object _key, final Object _value, final long _expiresAft */ protected void internalStore(final Object _key, final Object _value, final long _expiresAfter) { if (Constants.BUILD_STATS_ENABLED) { - recordKeeper.incrementTotalOperations(); + this.recordKeeper.incrementTotalOperations(); } if (_key != null && _value != null) { - final Item cachedValue = new Item(_value, currentTime, _expiresAfter); - managedCache.put(_key, cachedValue); + final Item cachedValue = new Item(_value, this.currentTime, _expiresAfter); + this.managedCache.put(_key, cachedValue); if (Constants.BUILD_STATS_ENABLED) { doAdaptiveAccounting(0); @@ -561,10 +598,10 @@ protected void tuneCache() { final float adaptiveRatio = getAdaptiveRatio(); if (adaptiveRatio > 0.5F) { log.debug(Messages.getString("CacheDecorator.read_optimizations_on") + adaptiveRatio); //$NON-NLS-1$ - managedCache.setMostlyRead(true); + this.managedCache.setMostlyRead(true); } else { log.debug(Messages.getString("CacheDecorator.read_optimizations_off") + adaptiveRatio); //$NON-NLS-1$ - managedCache.setMostlyRead(false); + this.managedCache.setMostlyRead(false); } } @@ -573,15 +610,15 @@ protected void tuneCache() { */ protected void expireItems() { // Sort the entries in the cache. - final List entries = new LinkedList(new ConcurrentHashMap(managedCache).entrySet()); - CollectionUtils.filter(entries, new ExpirationTimePredicate(currentTime)); + final List entries = new LinkedList(new ConcurrentHashMap(this.managedCache).entrySet()); + CollectionUtils.filter(entries, new ExpirationTimePredicate(this.currentTime)); final Object[] args = { new Integer(entries.size()) }; log.debug(Messages.getCompoundString("CacheDecorator.expiration_count", args)); //$NON-NLS-1$ for (final Iterator i = entries.iterator(); i.hasNext();) { final Map.Entry entry = (Entry) i.next(); if (entry != null) { // log.trace("Removing: " + entry.getKey()); - managedCache.remove(entry.getKey()); + this.managedCache.remove(entry.getKey()); } } } diff --git a/src/java/com/whirlycott/cache/RecordKeeper.java b/src/java/com/whirlycott/cache/RecordKeeper.java index 06d0bc1..97265c8 100644 --- a/src/java/com/whirlycott/cache/RecordKeeper.java +++ b/src/java/com/whirlycott/cache/RecordKeeper.java @@ -33,10 +33,17 @@ public class RecordKeeper implements Serializable { /** The total number of cache hits. */ private volatile long hits; - + /** Lock used for the hits value. */ private final Object hitLock = new Object(); + /** The total number of cache misses. */ + private volatile long misses; + + /** Lock used for the misses value. */ + private final Object missLock = new Object(); + + /** The total number of cache questions. */ private volatile long totalOperations; @@ -55,13 +62,12 @@ public long getHits() { } /** - * @param hits - * The hits to set. + * @return Returns the number of cache misses. */ - public void setHits(final long hits) { - this.hits = hits; + public long getMisses() { + return misses; } - + /** * @return Returns the totalOperations. */ @@ -82,6 +88,13 @@ public void incrementHits() { hits++; } } + + /** Increment misses. */ + public void incrementMisses() { + synchronized (missLock) { + misses++; + } + } public void startTuneCycle() { totalOperationsStartTuneCycle = totalOperations;