Bug 37345 javaElementFilters extension point isn't robust against errors in the plugin.xml
1) create a javaElementFilters extension, but leave the markup in the plugin.xml incomplete 2) start-up the workbench -> the package explorer doesn't come up The reason is that the javaElementFilters extension point implementation fires an assertion when the xml isn't complete. This is not correct since this isn't a programming error. In addition, an error in the plugin.xml shouldn't never block the workbench from properly coming up.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/filters/FilterDescriptor.java
}
	
	
	
	/**
	 * Returns the filter's id.
	 * <p>
	 * This attribute is mandatory for custom filters.
	 * The ID for pattern filters is
	 * PATTERN_FILTER_ID_PREFIX plus the pattern itself.
	 * </p>
	 */
	public String getId() {
		if (isPatternFilter()) {
			String viewId= getViewId();
			if (viewId == null)
				return PATTERN_FILTER_ID_PREFIX + getPattern();
			else
				return viewId + PATTERN_FILTER_ID_PREFIX + getPattern();
		} else
			return fElement.getAttribute(ID_ATTRIBUTE);
	}
	
	/**
	 * Returns the filter's name.
	 * <p>
	 * If the name of a pattern filter is missing
	 * then the pattern is used as its name.
	 * </p>
	 */