Bugzilla 50988: Fixed a NullPointerException in case a fo:character was removed due to white-space handling.

Thanks to Matthias Reischenbacher.

git-svn-id: https://svn.apache.org/repos/asf/xmlgraphics/fop/trunk@1088242 13f79535-47bb-0310-9956-ffa450edef68

src/java/org/apache/fop/fo/FObjMixed.java

@@ -50,6 +50,7 @@ public abstract class FObjMixed extends FObj {
     }
 
     /** {@inheritDoc} */
+    @Override
     protected void characters(char[] data, int start, int length,
                                  PropertyList pList,
                                  Locator locator) throws FOPException {
@@ -64,6 +65,7 @@ public abstract class FObjMixed extends FObj {
     }
 
     /** {@inheritDoc} */
+    @Override
     protected void endOfNode() throws FOPException {
 
         super.endOfNode();
@@ -150,6 +152,7 @@ public abstract class FObjMixed extends FObj {
     }
 
     /** {@inheritDoc} */
+    @Override
     protected void addChildNode(FONode child) throws FOPException {
 
         flushText();
@@ -169,6 +172,17 @@ public abstract class FObjMixed extends FObj {
     }
 
     /** {@inheritDoc} */
+    @Override
+    public void removeChild(FONode child) {
+        super.removeChild(child);
+        if (child == this.currentTextNode) {
+            // reset to following sibling
+            this.currentTextNode = child.siblings != null ? child.siblings[1] : null;
+        }
+    }
+
+    /** {@inheritDoc} */
+    @Override
     public void finalizeNode() throws FOPException {
 
         flushText();
@@ -183,6 +197,7 @@ public abstract class FObjMixed extends FObj {
      *
      * @return iterator for this object
      */
+    @Override
     public CharIterator charIterator() {
         return new RecursiveCharIterator(this);
     }

test/layoutengine/standard-testcases/block_white-space_bug50988.xml

@@ -0,0 +1,43 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+  Licensed to the Apache Software Foundation (ASF) under one or more
+  contributor license agreements.  See the NOTICE file distributed with
+  this work for additional information regarding copyright ownership.
+  The ASF licenses this file to You under the Apache License, Version 2.0
+  (the "License"); you may not use this file except in compliance with
+  the License.  You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License.
+-->
+<!-- $Id$ -->
+<testcase>
+  <info>
+    <p>
+      This test checks for a potential NullPointerException due to white-space removal.
+      See also: https://issues.apache.org/bugzilla/show_bug.cgi?id=50988
+    </p>
+  </info>
+  <fo>
+    <fo:root xmlns:fo="http://www.w3.org/1999/XSL/Format">
+      <fo:layout-master-set>
+        <fo:simple-page-master master-name="even" page-height="210mm" page-width="148mm">
+          <fo:region-body margin="20mm"/>
+        </fo:simple-page-master>
+      </fo:layout-master-set>
+      <fo:page-sequence master-reference="even">
+        <fo:flow flow-name="xsl-region-body">
+          <fo:block><fo:character character=" " hyphenate="false"/></fo:block>
+          <fo:block><fo:character character=" " hyphenate="false"/><fo:character character="A" hyphenate="false"/></fo:block>
+        </fo:flow>
+      </fo:page-sequence>
+    </fo:root>
+  </fo>
+  <!-- Default checks only; should just not throw a NPE -->
+  <checks />
+</testcase>