Bug 69240 [reconciling] Editor shows "stale" compilation error
Eclipse has always has a small problem in that occaisionally it would show an error in the editor window (red-squiggly, with a marker) even though the error had been fixed and no longer appeared in the Tasks/Problem view. I usually just type "Space-Backspace" and save the file and it goes away. In 3.0, this is MUCH more frequent. I'm not 100% sure of the cause, but every time I've seen in it recently, file A will have a problem, and then I'll change file B to fix it. I'll pay more attention, and see if I can obtain any more details.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/text/JavaReconciler.java
private Control fControl;
		
		public ActivationListener(Control control) {
			fControl= control;
		}
		/*
		 * @see org.eclipse.swt.events.ShellListener#shellActivated(org.eclipse.swt.events.ShellEvent)
		 */
		public void shellActivated(ShellEvent e) {
			if (!fControl.isDisposed() && fControl.isVisible() && hasJavaModelChanged())
				JavaReconciler.this.forceReconciling();
		}
		
		/*
		 * @see org.eclipse.swt.events.ShellListener#shellDeactivated(org.eclipse.swt.events.ShellEvent)
		 */
		public void shellDeactivated(ShellEvent e) {
			setJavaModelChanged(false);
		}
	}
	
	/**
	 * Internal Java element changed listener
	 * 
	 * @since 3.0
	 */
	private class ElementChangedListener implements IElementChangedListener {