Here you can find the source of isSystemLookAndFeel()
public static boolean isSystemLookAndFeel()
//package com.java2s; /*/*from w ww . j a va 2 s. c o m*/ * Copyright 2012 jMethods, Inc. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ import javax.swing.UIManager; public class Main { public static boolean isSystemLookAndFeel() { String systemLookAndFeelClassName = UIManager.getSystemLookAndFeelClassName(); String currentLookAndFeelClassName = UIManager.getLookAndFeel().getClass().getName(); return systemLookAndFeelClassName.equals(currentLookAndFeelClassName); } }