Refactor to avoid unecessary instanceof call

git-svn-id: https://svn.apache.org/repos/asf/jakarta/commons/proper/collections/trunk@131693 13f79535-47bb-0310-9956-ffa450edef68

src/java/org/apache/commons/collections/iterators/ObjectGraphIterator.java

@@ -70,7 +70,7 @@ import org.apache.commons.collections.Transformer;
  * more efficient (and convenient) than using nested for loops to extract a list.
  * 
  * @since Commons Collections 3.1
- * @version $Revision: 1.2 $ $Date: 2004/05/03 11:38:49 $
+ * @version $Revision: 1.3 $ $Date: 2004/05/03 11:50:30 $
  * 
  * @author Stephen Colebourne
  */
@@ -148,23 +148,38 @@ public class ObjectGraphIterator implements Iterator {
                 root = null;
             }
         } else {
-            findNext(currentIterator);
+            findNextByIterator(currentIterator);
         }
     }
 
     /**
-     * Finds the next object in the iteration.
+     * Finds the next object in the iteration given any start object.
      * 
      * @param value  the value to start from
      */
     protected void findNext(Object value) {
         if (value instanceof Iterator) {
-            if (value != currentIterator) {
+            // need to examine this iterator
+            findNextByIterator((Iterator) value);
+        } else {
+            // next value found
+            currentValue = value;
+            hasNext = true;
+        }
+    }
+    
+    /**
+     * Finds the next object in the iteration given an iterator.
+     * 
+     * @param iterator  the iterator to start from
+     */
+    protected void findNextByIterator(Iterator iterator) {
+        if (iterator != currentIterator) {
             // recurse a level
             if (currentIterator != null) {
                 stack.push(currentIterator);
             }
-                currentIterator = (Iterator) value;
+            currentIterator = iterator;
         }
         
         while (currentIterator.hasNext() && hasNext == false) {
@@ -181,16 +196,10 @@ public class ObjectGraphIterator implements Iterator {
         } else {
             // current iterator exhausted, go up a level
             currentIterator = (Iterator) stack.pop();
-                findNext(currentIterator);
-            }
-        } else {
-            // next value found
-            currentValue = value;
-            hasNext = true;
+            findNextByIterator(currentIterator);
         }
     }
 
-    
     //-----------------------------------------------------------------------
     /**
      * Checks whether there are any more elements in the iteration to obtain.