Here you can find the source of invert(JComponent c)
Makes a Swing component inverted by swapping its foreground and background colors.
public static void invert(JComponent c)
//package com.java2s; /* ==================================================================== Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements. See the NOTICE file distributed with this work for additional information regarding copyright ownership. The ASF licenses this file to You 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 /*from w w w .j a v a2s.c o m*/ 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.*; import java.awt.*; public class Main { /** * <p>Makes a Swing component inverted by swapping its foreground * and background colors. Hint: Depending on your needs it might * also be a good idea to call <tt>c.setOpaque(true)</tt>.</p> */ public static void invert(JComponent c) { Color invBackground = c.getForeground(); Color invForeground = c.getBackground(); c.setBackground(invBackground); c.setForeground(invForeground); } }