[cp-patches] FYI: BasicTreeUI getPathForRow() can return null

[Mark Wielaard]

Hi,

While testing the jedit help system (looks pretty now!) I noticed that
BasicTreeUI uses getPathForRow() without checking whether the return
value is null. This patch adds the appropriate guards.

2006-12-03  Mark Wielaard  <[EMAIL PROTECTED]>

    * javax/swing/plaf/basic/BasicTreeUI.java (paint): Check whether
    path[k] is null.
    (isLastChild): Return false when path is null.

Committed,

Mark

Index: javax/swing/plaf/basic/BasicTreeUI.java
===================================================================
RCS file: /cvsroot/classpath/classpath/javax/swing/plaf/basic/BasicTreeUI.java,v
retrieving revision 1.154
diff -u -r1.154 BasicTreeUI.java
--- javax/swing/plaf/basic/BasicTreeUI.java	16 Aug 2006 19:28:49 -0000	1.154
+++ javax/swing/plaf/basic/BasicTreeUI.java	3 Dec 2006 16:04:38 -0000
@@ -1587,12 +1587,15 @@
         for (int i = startIndex; i <= endIndex; i++, k++)
           {
             path[k] = treeState.getPathForRow(i);
-            isLeaf[k] = treeModel.isLeaf(path[k].getLastPathComponent());
-            isExpanded[k] = tree.isExpanded(path[k]);
-            bounds[k] = getPathBounds(tree, path[k]);
+            if (path[k] != null)
+              {
+                isLeaf[k] = treeModel.isLeaf(path[k].getLastPathComponent());
+                isExpanded[k] = tree.isExpanded(path[k]);
+                bounds[k] = getPathBounds(tree, path[k]);
 
-            paintHorizontalPartOfLeg(g, clip, insets, bounds[k], path[k], i,
-                                     isExpanded[k], false, isLeaf[k]);
+                paintHorizontalPartOfLeg(g, clip, insets, bounds[k], path[k],
+                                         i, isExpanded[k], false, isLeaf[k]);
+              }
             if (isLastChild(path[k]))
               paintVerticalPartOfLeg(g, clip, insets, path[k]);
           }
@@ -1600,8 +1603,9 @@
         k = 0;
         for (int i = startIndex; i <= endIndex; i++, k++)
           {
-            paintRow(g, clip, insets, bounds[k], path[k], i, isExpanded[k],
-                     false, isLeaf[k]);
+            if (path[k] != null)
+              paintRow(g, clip, insets, bounds[k], path[k], i, isExpanded[k],
+                       false, isLeaf[k]);
           }
       }
   }
@@ -1611,7 +1615,9 @@
    */
   private boolean isLastChild(TreePath path)
   {
-    if (path instanceof GnuPath)
+    if (path == null)
+      return false;
+    else if (path instanceof GnuPath)
       {
         // Except the seldom case when the layout cache is changed, this
         // optimized code will be executed.