Changeset 15767 for greenstone3/trunk/src/java/org/greenstone/gsdl3/util/GSXML.java

Timestamp:

2008-05-28T16:22:47+12:00 (16 years ago)

Author:

ak19

Message:

Attempted fix for trac bug ticket #225 - NullPointerException. Possibly n is null at some time, so need to check for that before trying n.getFirstChild(). Null is returned, which the caller GSXML.getNodeByPath() and its caller GS2BrowseAction.classifierBrowse() already check for.

File:

• greenstone3/trunk/src/java/org/greenstone/gsdl3/util/GSXML.java (modified) (1 diff)

greenstone3/trunk/src/java/org/greenstone/gsdl3/util/GSXML.java

@@ -423 +423 @@
   /** returns the (first) child element with the given name */
   public static Node getChildByTagName(Node n, String name) {
-    
-    Node child = n.getFirstChild();
-    while (child!=null) {
-      if (child.getNodeName().equals(name)) {
-        return child;
-      }
-      child = child.getNextSibling();
-    }
-    return null; //not found
+      if(n != null) { // this line is an attempted solution to the NullPointerException mentioned 
+      // in trac bug ticket #225. If n is null can't do n.getFirstChild() below. As per bug #225: 
+      // GSXML.getNodeByPath() is called by GS2BrowseAction, which then calls this method.
+      // If n is null, null will be returned which GS2BrowseAction already checks for. It's here
+      // that the NullPointerException was thrown.
+ 
+      Node child = n.getFirstChild();
+      while (child!=null) {
+          if (child.getNodeName().equals(name)) {
+          return child;
+          }
+          child = child.getNextSibling();
+      }
+      }
+      return null; //not found
   }