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
* @see IWorkbenchPreferenceConstants#NO_NEW_PERSPECTIVE
	 */
	public static void updatePerspective(IConfigurationElement configElement) {
		
		
		if (configElement == null) {
			return;
		}
		
		String perspSetting = PrefUtil.getAPIPreferenceStore().getString(
				IDE.Preferences.PROJECT_OPEN_NEW_PERSPECTIVE);
		String promptSetting = IDEWorkbenchPlugin.getDefault()
				.getPreferenceStore().getString(
						IDEInternalPreferences.PROJECT_SWITCH_PERSP_MODE);
		
		if (!(promptSetting.equals(MessageDialogWithToggle.PROMPT))
				&& perspSetting
						.equals(IWorkbenchPreferenceConstants.NO_NEW_PERSPECTIVE)) {
			return;
		}
		
		String finalPerspId = configElement.getAttribute(FINAL_PERSPECTIVE);
		if (finalPerspId == null) {
			return;
		}
		
		IPerspectiveRegistry reg = PlatformUI.getWorkbench()
				.getPerspectiveRegistry();