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
} else {
			return JavaCore.getOptions();
		}	
	}
	
	protected Map getDefaultOptions() {
		return JavaCore.getDefaultOptions();
	}	
	
	public final boolean hasProjectSpecificOptions() {
		if (fProject != null) {
			Map settings= fProject.getOptions(false);
			String[] allKeys= getAllKeys();
			for (int i= 0; i < allKeys.length; i++) {
				if (settings.get(allKeys[i]) != null) {
					return true;
				}
			}
		}
		return false;
	}	
		
	protected final void setOptions(Map map) {
		if (fProject != null) {
			fProject.setOptions(map);
		} else {
			JavaCore.setOptions((Hashtable) map);
		}	
	}