com.privatejgoodies.forms.util.FormUtils Maven / Gradle / Ivy
/*
* Copyright (c) 2002-2013 JGoodies Software GmbH. All Rights Reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* o Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* o Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* o Neither the name of JGoodies Software GmbH nor the names of
* its contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
* OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
* EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package com.privatejgoodies.forms.util;
import javax.swing.LookAndFeel;
import javax.swing.UIManager;
/**
* A library-internal class that consists only of static utility methods.
*
* Note: This class is not part of the public Forms API. It's intended for library
* implementation purposes only. The class's API may change at any time.
*
* @author Karsten Lentzsch
* @version $Revision: 1.14 $
*
* @since 1.2
*/
public final class FormUtils {
// Instance *************************************************************
private FormUtils() {
// Suppresses default constructor, prevents instantiation.
}
// API ********************************************************************
/**
* Lazily checks and answers whether the Aqua look&feel is active.
*
* @return {@code true} if the current look&feel is Aqua
*/
public static boolean isLafAqua() {
ensureValidCache();
if (cachedIsLafAqua == null) {
cachedIsLafAqua = Boolean.valueOf(computeIsLafAqua());
}
return cachedIsLafAqua.booleanValue();
}
// Caching and Lazily Computing the Laf State *****************************
/**
* Clears cached internal Forms state that is based on the Look&Feel, for example dialog
* base units.
*
* There's typically no need to call this method directly. It'll be invoked automatically, if
* the L&F has been changed via {@link UIManager#setLookAndFeel} and cached data is
* requested. It's been made public to allow cache invalidation for cases where the L&F is
* changed temporarily by replacing the UIDefaults, for example in a visual editor.
*
* @since 1.2.1
*/
public static void clearLookAndFeelBasedCaches() {
cachedIsLafAqua = null;
DefaultUnitConverter.getInstance().clearCache();
}
/**
* Holds the LookAndFeel that has been used to computed cached values. If the current L&F
* differs from this cached value, the caches must be cleared.
*/
private static LookAndFeel cachedLookAndFeel;
/**
* Holds the cached result of the Aqua l&f check. Is invalidated if a look&feel change
* has been detected in {@code #ensureValidCache}.
*/
private static Boolean cachedIsLafAqua;
/**
* Computes and answers whether an Aqua look&feel is active. This may be Apple's Aqua
* L&f, or a sub-L&f that uses the same ID, because it doesn't substantially change the
* look.
*
* @return true if the current look&feel is Aqua
*/
private static boolean computeIsLafAqua() {
return UIManager.getLookAndFeel().getID().equals("Aqua");
}
static void ensureValidCache() {
LookAndFeel currentLookAndFeel = UIManager.getLookAndFeel();
if (currentLookAndFeel != cachedLookAndFeel) {
clearLookAndFeelBasedCaches();
cachedLookAndFeel = currentLookAndFeel;
}
}
}