Bug 241849 [Markers] Need a property tester to test the marker type of a MarkerEntry
Build ID: I20080617-2000 Steps To Reproduce: There is no property tester defined in org.eclipse.ui.ide for testing the marker type of a MarkerEntry in a marker view. Such a tester would be very useful for clients who are trying to add popup menu items to a marker view. I could define a property tester in my own plug-in for testing the marker type, but then I run in to plug-in activation issues. It would be better for the tester to be defined in a lower-level plug-in. More information: In 3.4, the marker views no longer support using object contributions to add to the popup menu. This means that existing object contributions need to be migrated to the command/handler infrastructure. However, with object contributions, it was possible to control visibility and enablement using the filters defined in IMarkerActionFilter. The command/handler infrastructure uses property testers to accomplish this sort of filtering instead; it would be nice for the platform to define property testers equivalent to these filters to make migration easier.
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/internal/ide/model/WorkbenchMarker.java
IMarkerActionFilter {
    /*
     *  (non-Javadoc)
     * @see org.eclipse.ui.model.IWorkbenchAdapter#getImageDescriptor(java.lang.Object)
     */
    public ImageDescriptor getImageDescriptor(Object o) {
        if (!(o instanceof IMarker)) {
			return null;
		}
        return IDEWorkbenchPlugin.getDefault().getMarkerImageProviderRegistry()
                .getImageDescriptor((IMarker) o);
    }
    /*
     *  (non-Javadoc)
     * @see org.eclipse.ui.model.IWorkbenchAdapter#getLabel(java.lang.Object)
     */
    public String getLabel(Object o) {
        IMarker marker = (IMarker) o;
        return marker.getAttribute(IMarker.MESSAGE, "");
    }
    /*
     *  (non-Javadoc)
     * @see org.eclipse.ui.model.IWorkbenchAdapter#getParent(java.lang.Object)