Merged BRANCHES/DEV/mward/head_cachestats to HEAD:

89575: ACE-3327: Work In Progress. TX cache statistics.
   89642: ACE-3327: Exposes statistics through JMX. Adds hit ratio.
   89649: ACE-3327: Added "@since 5.0" to new classes.
   89691: ACE-3327: improved TransactionalCache stats tests.
   89743: ACE-3327: fixed lack of thread safety for InMemoryCacheStatistics.
   89752: ACE-3327: now possible to disable/enable tx cache statistics per-cache with properties.



git-svn-id: https://svn.alfresco.com/repos/alfresco-enterprise/alfresco/HEAD/root@89798 c4b6b30b-aa2e-2d43-bbcb-ca4b014f7261

source/java/org/alfresco/repo/cache/TransactionStats.java

@@ -0,0 +1,80 @@
+/*
+ * Copyright (C) 2005-2014 Alfresco Software Limited.
+ *
+ * This file is part of Alfresco
+ *
+ * Alfresco is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Alfresco 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.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with Alfresco. If not, see <http://www.gnu.org/licenses/>.
+ */
+package org.alfresco.repo.cache;
+
+import java.util.HashMap;
+import java.util.Map;
+
+import org.apache.commons.math3.stat.descriptive.SummaryStatistics;
+
+/**
+ * Only to be used within a single transaction/thread.
+ * 
+ * @since 5.0
+ * @author Matt Ward
+ */
+public class TransactionStats
+{
+    private Map<OpType, SummaryStatistics> timings = new HashMap<>();
+    
+    /**
+     * Cache operation type.
+     */
+    public enum OpType
+    {
+        GET_HIT,
+        GET_MISS,
+        PUT,
+        REMOVE,
+        CLEAR
+    }
+    
+    public long getCount(OpType op)
+    {
+        SummaryStatistics stats = getTimings(op);
+        return stats.getN();
+    }
+    
+    public SummaryStatistics getTimings(OpType op)
+    {
+        SummaryStatistics opTimings = timings.get(op);
+        if (opTimings == null)
+        {
+            opTimings = new SummaryStatistics();
+            timings.put(op, opTimings);
+        }
+        return opTimings;
+    }
+    
+    public void record(long start, long end, OpType op)
+    {   
+        if (end < start)
+        {
+            throw new IllegalArgumentException("End time [" + end + "] occurs before start time [" + start + "].");
+        }
+        double timeTaken = end - start;
+        addTiming(op, timeTaken);
+    }
+
+    private void addTiming(OpType op, double time)
+    {
+        SummaryStatistics opTimings = getTimings(op);
+        opTimings.addValue(time);
+    }
+}