content: /*
   * Created on Mar 30, 2008
   *
   * 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.
   *
   * Copyright @2008-2013 the original author or authors.
   */
  package org.fest.swing.core;
  
  import static org.fest.swing.awt.AWT.invokerOf;
  
  import java.awt.Component;
  import java.awt.Window;
  
  import javax.annotation.Nonnull;
  import javax.annotation.Nullable;
  import javax.swing.MenuElement;
  
  import org.fest.swing.annotation.RunsInCurrentThread;
  import org.fest.swing.hierarchy.ComponentHierarchy;
  import org.fest.swing.hierarchy.ExistingHierarchy;
  
  /**
   * Looks up an AWT or Swing {@code Component}'s {@code Window} ancestor.
   *
   * @author Yvonne Wang
   */
  public final class WindowAncestorFinder {
    private static ComponentHierarchy hierarchy = new ExistingHierarchy();
  
    /**
     * <p>
     * Similar to {@code javax.swing.SwingUtilities#getWindowAncestor(Component)}, but returns the AWT or Swing
     * {@code Component} itself if it is a {@code Window}, or the invoker's {@code Window} if on a pop-up.
     * </p>
     *
     * <p>
     * <b>Note:</b> This method is accessed in the current executing thread. Such thread may or may not be the event
     * dispatch thread (EDT.) Client code must call this method from the EDT.
     * </p>
     *
     * @param c the {@code Component} to get the {@code Window} ancestor of.
     * @return the {@code Window} ancestor of the given {@code Component}, the {@code Component} itself if it is a
     *         {@code Window}, or the invoker's {@code Window} if on a pop-up.
     */
    @RunsInCurrentThread
    public static @Nullable Window windowAncestorOf(@Nonnull Component c) {
      return findWindowAncestor(c);
    }
  
    @RunsInCurrentThread
    private static @Nullable Window findWindowAncestor(@Nullable Component c) {
      if (c == null) {
        return null;
      }
      if (c instanceof Window) {
        return (Window) c;
      }
      if (c instanceof MenuElement) {
        Component invoker = invokerOf(c);
        if (invoker != null) {
          return windowAncestorOf(invoker);
        }
      }
      return findWindowAncestor(hierarchy.parentOf(c));
    }
  
    private WindowAncestorFinder() {}
  }
  