Java tutorial
/* * Copyright (c) 2010, 2016, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package javafx.scene.paint; import com.sun.javafx.beans.event.AbstractNotifyListener; import com.sun.javafx.tk.Toolkit; /** * Base class for a color or gradients used to fill shapes and backgrounds when * rendering the scene graph. * @since JavaFX 2.0 */ public abstract class Paint { static { Toolkit.setPaintAccessor(new Toolkit.PaintAccessor() { @Override public boolean isMutable(Paint paint) { return paint.acc_isMutable(); } @Override public Object getPlatformPaint(Paint paint) { return paint.acc_getPlatformPaint(); } @Override public void addListener(Paint paint, AbstractNotifyListener platformChangeListener) { paint.acc_addListener(platformChangeListener); } @Override public void removeListener(Paint paint, AbstractNotifyListener platformChangeListener) { paint.acc_removeListener(platformChangeListener); } }); } /** * Only allow classes in this package to subclass Paint */ Paint() { } boolean acc_isMutable() { return false; } abstract Object acc_getPlatformPaint(); void acc_addListener(AbstractNotifyListener platformChangeListener) { throw new UnsupportedOperationException("Not Supported."); } void acc_removeListener(AbstractNotifyListener platformChangeListener) { throw new UnsupportedOperationException("Not Supported."); } /** * Gets whether this Paint is completely opaque. An opaque paint is one that * has no alpha component in any of its colors. It may be possible for a Paint * to be opaque and yet return false, if it cannot be easily determined * whether the paint is actually opaque. For example, the ImagePattern may not * be able to cheaply determine its opacity. * * @return true if the Paint is opaque, false if it is not opaque or if * it cannot be determined. * @since JavaFX 8.0 */ public abstract boolean isOpaque(); /** * Creates a paint value from a string representation. Recognizes strings * representing {@code Color}, {@code RadialGradient} or {@code LinearGradient}. * String specifying LinearGradient must begin with linear-gradient keyword * and string specifying RadialGradient must begin with radial-gradient. * * @param value the string to convert * @throws NullPointerException if {@code value} is {@code null} * @throws IllegalArgumentException if {@code value} cannot be parsed * @return a {@code Color}, {@code RadialGradient} or {@code LinearGradient} * object holding the value represented by the string argument. * * @see Color#valueOf(String) * @see LinearGradient#valueOf(String) * @see RadialGradient#valueOf(String) * @since JavaFX 2.1 */ public static Paint valueOf(String value) { if (value == null) { throw new NullPointerException("paint must be specified"); } if (value.startsWith("linear-gradient(")) { return LinearGradient.valueOf(value); } else if (value.startsWith("radial-gradient(")) { return RadialGradient.valueOf(value); } else { return Color.valueOf(value); } } }