Bug 11814 OpenExternalJavadoc action should not call findElement on JAR
This causes an exception: Java Model Exception: Java Model Status [Invalid path: C:/Java/IBM1.3/jre/lib/rt.jar.] at org.eclipse.jdt.internal.core.JavaProject.findElement(JavaProject.java:435) at org.eclipse.jdt.internal.ui.actions.OpenExternalJavadocAction.run(OpenExternalJavadocAction.java:102) at org.eclipse.ui.texteditor.RetargetTextEditorAction.run(RetargetTextEditorAction.java:103) at org.eclipse.jface.action.Action.runWithEvent(Action.java:473) at org.eclipse.jface.action.ActionContributionItem.handleWidgetSelection(ActionContributionItem.java:407) at org.eclipse.jface.action.ActionContributionItem.handleWidgetEvent(ActionContributionItem.java(Compiled Code)) at org.eclipse.jface.action.ActionContributionItem$ActionListener.handleEvent(ActionContributionItem.java(Compiled Code)) at org.eclipse.jface.action.ActionContributionItem$ActionListener.handleEvent(ActionContributionItem.java(Compiled Code)) at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java(Compiled Code)) at org.eclipse.swt.widgets.Widget.notifyListeners(Widget.java(Compiled Code)) at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java(Compiled Code)) at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java(Compiled Code)) at org.eclipse.ui.internal.Workbench.runEventLoop(Workbench.java(Compiled Code)) at org.eclipse.ui.internal.Workbench.run(Workbench.java:698) at org.eclipse.core.internal.boot.InternalBootLoader.run(InternalBootLoader.java:777) at org.eclipse.core.boot.BootLoader.run(BootLoader.java:319) at java.lang.reflect.Method.invoke(Native Method) at org.eclipse.core.launcher.Main.basicRun(Main.java:196) at org.eclipse.core.launcher.Main.run(Main.java:555) at org.eclipse.core.launcher.UIMain.main(UIMain.java:52) 4 org.eclipse.jdt.core 979 Invalid path: C:/Java/IBM1.3/jre/lib/rt.jar.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/wizards/buildpaths/SourceAttachmentBlock.java
DirectoryDialog dialog= new DirectoryDialog(getShell());
		dialog.setText(NewWizardMessages.getString("SourceAttachmentBlock.jdocdialog.text")); 
		dialog.setMessage(NewWizardMessages.getString("SourceAttachmentBlock.jdocdialog.message")); 
		dialog.setFilterPath(initPath);
		String res= dialog.open();
		if (res != null) {
			try {
				return (new File(res)).toURL();
			} catch (MalformedURLException e) {
				
				JavaPlugin.log(e);
			}
		}
		return null;		
		
	}
		
	private Shell getShell() {
		if (fSWTWidget != null) {
			return fSWTWidget.getShell();
		}
		return JavaPlugin.getActiveWorkbenchShell();			
	}
	
	/**
	 * Takes a path and replaces the beginning with a variable name
	 * (if the beginning matches with the variables value)
	 */
	private IPath modifyPath(IPath path, String varName) {
		if (varName == null || path == null) {