[BATIK-1144] a text animation faults with null pointer exception, when scripting with java

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 1.8
• Component/s: Animation engine, Bridge, Scripting
• Environment: first noticed on windows 7, jdk 1.8
• Assignee: Unassigned
• Reporter: mitchell bass
• Created: 24/Mar/16 19:58
• Updated: 19/Sep/17 11:43

Description

when trying to dynamically animate a color change for a text element, got a null pointer exception in the SVGOMAnimationElement:beginElement() method because getSvgContext was returning null.

introspection with a debugger turned up the fact that in SVGTextElementBridge.handleDOMNodeInsertedEvent(MutationEvent evt) the setting of the svg context was not being done. this is called when the animation element is appended as a child to the text element.

SVGTextElementBridge extends AbstractGraphicsNodeBridge and in particular overrides handleDOMNodeInsertedEvent(MutationEvent evt) which would normally set the svg context.

as a local fix changing SVGTextElementBridge.handleDOMNodeInsertedEvent(MutationEvent evt) and how it handles an ELEMENT node from:

    public void handleDOMNodeInsertedEvent(MutationEvent evt) {
        Node childNode = (Node)evt.getTarget();

        //check the type of the node inserted before discard the layout
        //in the case of <title> or <desc> or <metadata>, the layout
        //is unchanged
        switch(childNode.getNodeType()) {
            case Node.TEXT_NODE:        // fall-through is intended
            case Node.CDATA_SECTION_NODE:
                laidoutText = null;
                break;
            case Node.ELEMENT_NODE: {
                Element childElement = (Element)childNode;
                if (isTextChild(childElement)) {
                    addContextToChild(ctx, childElement);
                    laidoutText = null;
                }
                break;
            }
        }
        if (laidoutText == null) {
            computeLaidoutText(ctx, e, getTextNode());
        }
    }

–
to fix, added else to isTextChild conditional, to:

    public void handleDOMNodeInsertedEvent(MutationEvent evt) {
        Node childNode = (Node)evt.getTarget();

        //check the type of the node inserted before discard the layout
        //in the case of <title> or <desc> or <metadata>, the layout
        //is unchanged
        switch(childNode.getNodeType()) {
            case Node.TEXT_NODE:        // fall-through is intended
            case Node.CDATA_SECTION_NODE:
                laidoutText = null;
                break;
            case Node.ELEMENT_NODE: {
                Element childElement = (Element)childNode;
                if (isTextChild(childElement)) {
                    addContextToChild(ctx, childElement);
                    laidoutText = null;
                }
               // ADDED ELSE so animation nodes get std treatment
                else {
                        super.handleDOMNodeInsertedEvent(evt);
                }
                break;
            }
        }
        if (laidoutText == null) {
            computeLaidoutText(ctx, e, getTextNode());
        }
    }

–

not clear that this is a complete fix or not.