Bug 219901 [Undo] new file creation subjec to Undo (file deleted without warning)
when creating a new file by right clicking on your project in the project explorer new->file this action is put on the undo/redo stack. Pressing Ctrl-Z to undo this action will thus delete your file. As this stack is separate from the stack in the editor , one can create a new file, work for a long time, then inadvertently press ctrl-z to undo a code change while having the focus on the project explorer and irrevocably lose their file. Redo will create a new EMPTY file; the work is gone, forever. This appears to only work for the "new file", not for "new->source file" etc. Although some may perceive this as a feature, it is hard to imagine a scenario where ctrl-z should permanently delete a file without warning.
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/wizards/newresource/BasicNewProjectResourceWizard.java
ArrayList preferredPerspIds = new ArrayList();
		addPerspectiveAndDescendants(preferredPerspIds, finalPerspId);
		String preferred = configElement.getAttribute(PREFERRED_PERSPECTIVES);
		if (preferred != null) {
			StringTokenizer tok = new StringTokenizer(preferred, " \t\n\r\f,"); 
			while (tok.hasMoreTokens()) {
				addPerspectiveAndDescendants(preferredPerspIds, tok.nextToken());
			}
		}
		IWorkbenchWindow window = PlatformUI.getWorkbench()
				.getActiveWorkbenchWindow();
		if (window != null) {
			IWorkbenchPage page = window.getActivePage();
			if (page != null) {
				IPerspectiveDescriptor currentPersp = page.getPerspective();
				
				
				if (currentPersp != null
						&& preferredPerspIds.contains(currentPersp.getId())) {
					return;
				}
			}
			
			if (!confirmPerspectiveSwitch(window, finalPersp)) {
				return;
			}
		}
		int workbenchPerspectiveSetting = WorkbenchPlugin.getDefault()
				.getPreferenceStore().getInt(