[jbosscache-commits] JBoss Cache SVN: r6835 - in core/trunk/src/main/java/org/jboss/cache: util and 1 other directory.

[jbosscache-commits at lists.jboss.org]

Author: manik.surtani at jboss.com
Date: 2008-10-03 11:12:19 -0400 (Fri, 03 Oct 2008)
New Revision: 6835

Modified:
   core/trunk/src/main/java/org/jboss/cache/UnversionedNode.java
   core/trunk/src/main/java/org/jboss/cache/util/FastCopyHashMap.java
Log:
JBCACHE-1082:  Optimise nodes for single elements

Modified: core/trunk/src/main/java/org/jboss/cache/UnversionedNode.java
===================================================================
--- core/trunk/src/main/java/org/jboss/cache/UnversionedNode.java	2008-10-03 13:27:23 UTC (rev 6834)
+++ core/trunk/src/main/java/org/jboss/cache/UnversionedNode.java	2008-10-03 15:12:19 UTC (rev 6835)
@@ -33,6 +33,7 @@
 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.Map;
+import java.util.Map.Entry;
 import java.util.Set;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.ConcurrentMap;
@@ -49,13 +50,13 @@
    /**
     * Debug log.
     */
-   static Log log = LogFactory.getLog(UnversionedNode.class);
+   protected static Log log = LogFactory.getLog(UnversionedNode.class);
    protected static final boolean trace = log.isTraceEnabled();
 
    /**
     * Map of general data keys to values.
     */
-   protected FastCopyHashMap<K, V> data;
+   protected Map<K, V> data;
    protected NodeSPI<K, V> delegate;
    protected CacheSPI<K, V> cache;
 
@@ -137,10 +138,10 @@
    }
 
    // does not need to be synchronized since this will only be accessed by a single thread in MVCC thanks to the write lock.
-   private void initDataMap()
-   {
-      if (data == null) data = new FastCopyHashMap<K, V>();
-   }
+//   private void initDataMap()
+//   {
+//      if (data == null) data = new FastCopyHashMap<K, V>();
+//   }
 
    public CacheSPI<K, V> getCache()
    {
@@ -170,7 +171,19 @@
 
    public V put(K key, V value)
    {
-      if (data == null) initDataMap();
+      if (data == null)
+      {
+         // new singleton map!
+         data = Collections.singletonMap(key, value);
+         return null;
+      }
+      if (data.size() == 1 && data.containsKey(key))
+      {
+         V oldVal = data.get(key);
+         data = Collections.singletonMap(key, value);
+         return oldVal;
+      }
+      upgradeDataMap();
       return data.put(key, value);
    }
 
@@ -280,7 +293,19 @@
    public V remove(K key)
    {
       if (data == null) return null;
-      return data.remove(key);
+      V value;
+      if (data instanceof FastCopyHashMap)
+      {
+         value = data.remove(key);
+         downgradeDataMapIfNeeded();
+      }
+      else
+      {
+         // singleton maps cannot remove!
+         value = data.get(key);
+         data = null;
+      }
+      return value;
    }
 
    public void printDetails(StringBuilder sb, int indent)
@@ -388,7 +413,8 @@
 
    public void clear()
    {
-      if (data != null) data.clear();
+      data = null;
+//      if (data != null) data.clear();
    }
 
    @SuppressWarnings("unchecked")
@@ -428,11 +454,38 @@
    {
       if (data != null)
       {
-         if (this.data == null) initDataMap();
-         this.data.putAll(data);
+         if (this.data == null)
+            copyDataMap(data);
+         else
+         if (this.data.size() == 1 && data.size() == 1 && this.data.keySet().iterator().next().equals(data.keySet().iterator().next()))
+         {
+            // replace key!
+            Entry<? extends K, ? extends V> e = data.entrySet().iterator().next();
+            this.data = Collections.singletonMap(e.getKey(), e.getValue());
+         }
+         else
+         {
+            // size. Do we need to update the existing data map to a FCHM?
+            upgradeDataMap();
+            this.data.putAll(data);
+         }
       }
    }
 
+   protected final void upgradeDataMap()
+   {
+      if (data != null && !(data instanceof FastCopyHashMap)) data = new FastCopyHashMap<K, V>(data);
+   }
+
+   protected final void downgradeDataMapIfNeeded()
+   {
+      if (data.size() == 1 && data instanceof FastCopyHashMap)
+      {
+         Entry<K, V> e = data.entrySet().iterator().next();
+         data = Collections.singletonMap(e.getKey(), e.getValue());
+      }
+   }
+
    public void removeChildren()
    {
       children.clear();
@@ -556,7 +609,7 @@
    public InternalNode<K, V> copy()
    {
       UnversionedNode<K, V> n = new UnversionedNode<K, V>(fqn, cache, isFlagSet(LOCK_FOR_CHILD_INSERT_REMOVE));
-      if (data != null) n.data = (FastCopyHashMap<K, V>) data.clone();
+      n.data = copyDataMap(data);
       copyInternals(n);
       return n;
    }
@@ -573,7 +626,7 @@
    {
       if (data == null)
       {
-         data = state == null ? new FastCopyHashMap<K, V>() : new FastCopyHashMap<K, V>(state);
+         data = copyDataMap(state);
       }
       else
       {
@@ -582,6 +635,29 @@
       }
    }
 
+   protected final Map copyDataMap(Map<? extends K, ? extends V> toCopyFrom)
+   {
+      if (toCopyFrom != null && toCopyFrom.size() > 0)
+      {
+         Map map;
+         if (toCopyFrom instanceof FastCopyHashMap)
+         {
+            map = (FastCopyHashMap<K, V>) ((FastCopyHashMap<K, V>) toCopyFrom).clone();
+         }
+         else if (toCopyFrom.size() == 1)
+         {
+            Entry<? extends K, ? extends V> e = toCopyFrom.entrySet().iterator().next();
+            map = Collections.singletonMap(e.getKey(), e.getValue());
+         }
+         else
+         {
+            map = new FastCopyHashMap<K, V>(toCopyFrom);
+         }
+         return map;
+      }
+      return null;
+   }
+
    public Map getInternalState(boolean onlyInternalState)
    {
       if (onlyInternalState)

Modified: core/trunk/src/main/java/org/jboss/cache/util/FastCopyHashMap.java
===================================================================
--- core/trunk/src/main/java/org/jboss/cache/util/FastCopyHashMap.java	2008-10-03 13:27:23 UTC (rev 6834)
+++ core/trunk/src/main/java/org/jboss/cache/util/FastCopyHashMap.java	2008-10-03 15:12:19 UTC (rev 6835)
@@ -53,7 +53,7 @@
    /**
     * Same default as HashMap, must be a power of 2
     */
-   private static final int DEFAULT_CAPACITY = 16;
+   private static final int DEFAULT_CAPACITY = 8;
 
    /**
     * MAX_INT - 1