Avoid creating a new array when we notify our observers in SAFE_IN_ORDER

mode unless our list has grown since we last issued a notification.


git-svn-id: https://samskivert.googlecode.com/svn/trunk@1707 6335cc39-0255-0410-8fd6-9bcaacd3b74c

projects/samskivert/src/java/com/samskivert/util/ObserverList.java

@@ -181,11 +181,14 @@ public class ObserverList extends ArrayList
             // create a snapshot of the observer array at the time we
             // start the notification to ensure that modifications to the
             // array during notification don't hose us
-            Object[] obs = toArray();
-            int ocount = obs.length;
+            int ocount = size();
+            if (_snap == null || _snap.length < ocount) {
+                _snap = new Object[ocount];
+            }
+            Object[] obs = toArray(_snap);
             for (int ii = 0; ii < ocount; ii++) {
-                if (!checkedApply(obop, obs[ii])) {
-                    remove(obs[ii]);
+                if (!checkedApply(obop, _snap[ii])) {
+                    remove(_snap[ii]);
                 }
             }
 
@@ -224,6 +227,10 @@ public class ObserverList extends ArrayList
     /** Whether to allow observers to observe more than once simultaneously. */
     protected boolean _allowDups;
 
+    /** Used to avoid creating a new snapshot array every time we notify
+     * our observers if the size has not changed. */
+    protected Object[] _snap;
+
     /** Message reported for unsupported <code>add()</code> variants. */
     protected static final String UNSUPPORTED_ADD_MESSAGE =
         "Observers may only be added via ObserverList.add(Object).";