Bug 31395 Child window of Preferences dialog centers between screens
On the Preferences->Java->Code Generation->Names tab, the Edit button opens a dialog that is split between multiple monitors, instead of centering on the main Preference window like the rest of its child windows do.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/preferences/OptionsConfigurationBlock.java
}		
	
	protected void controlChanged(Widget widget) {
		ControlData data= (ControlData) widget.getData();
		String newValue= null;
		if (widget instanceof Button) {
			newValue= data.getValue(((Button)widget).getSelection());			
		} else if (widget instanceof Combo) {
			newValue= data.getValue(((Combo)widget).getSelectionIndex());
		} else {
			return;
		}
		fWorkingValues.put(data.getKey(), newValue);
		
		validateSettings(data.getKey(), newValue);
	}
	
	protected void textChanged(Text textControl) {
		String key= (String) textControl.getData();
		String number= textControl.getText();
		fWorkingValues.put(key, number);
		validateSettings(key, number);
	}	
	protected boolean checkValue(String key, String value) {
		return value.equals(fWorkingValues.get(key));
	}
	
	/* (non-javadoc)
	 * Update fields and validate.
	 * @param changedKey Key that changed, or null, if all changed.