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/*
 * Copyright (c) 2010, 2017, 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,
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package javafx.css;

import java.util.Collections;
import java.util.List;
import javafx.scene.Node;

/**
 * A CssMetaData instance provides information about the CSS style and
 * provides the hooks that allow CSS to set a property value.
 * It encapsulates the CSS property name, the type into which the CSS value
 * is converted, and the default value of the property.
 * 

* CssMetaData is the bridge between a value that can be represented * syntactically in a .css file, and a {@link StyleableProperty}. There is * a one-to-one correspondence between a CssMetaData and a StyleableProperty. * Typically, the CssMetaData of a Node will include the CssMetaData of its ancestors. * For example, the CssMetaData of a Rectangle includes the CssMetaData of Shape and also of Node. * During CSS processing, the CSS engine iterates over the Node's CssMetaData, * looks up the parsed value of each {@link javafx.css.CssMetaData#getProperty() property}, * converts the parsed value, and sets the value on the StyleableProperty. *

* The method {@link Node#getCssMetaData()} is called to obtain the * List<CssMetaData>. This method is called frequently and it is prudent * to return a static list rather than creating the list on each call. By * convention, node classes that have CssMetaData will implement a * static method {@code getClassCssMetaData()} and it is customary to have * {@code getCssMetaData()} simply return {@code getClassCssMetaData()}. The * purpose of {@code getClassCssMetaData()} is to allow sub-classes to easily * include the CssMetaData of some ancestor. *

The {@link javafx.css.StyleablePropertyFactory StyleablePropertyFactory} * greatly simplifies creating a StyleableProperty and its corresponding CssMetaData.

*

* This example is a typical implementation. *


 * private DoubleProperty gapProperty = new StyleableDoubleProperty(0) {
 *     {@literal @}Override
 *      public CssMetaData{@literal <}MyWidget,Number{@literal >} getCssMetaData() {
 *          return GAP_META_DATA;
 *      }
 *
 *      {@literal @}Override
 *      public Object getBean() {
 *          return MyWidget.this;
 *      }
 *
 *      {@literal @}Override
 *      public String getName() {
 *          return "gap";
 *      }
 * };
 *
 * private static final CssMetaData GAP_META_DATA =
 *     new CssMetaData{@literal <}MyWidget,Number{@literal >}("-my-gap", StyleConverter.getSizeConverter(), 0d) {
 *
 *        {@literal @}Override
 *        public boolean isSettable(MyWidget node) {
 *            return node.gapProperty == null || !node.gapProperty.isBound();
 *        }
 *
 *        {@literal @}Override
 *        public StyleableProperty{@literal <}Number{@literal >} getStyleableProperty(MyWidget node) {
 *            return (StyleableProperty{@literal <}Number{@literal >})node.gapProperty;
 *        }
 * };
 *
 * private static final List{@literal <}CssMetaData{@literal <}? extends Node, ?{@literal >}{@literal >} cssMetaDataList;
 * static {
 *     List{@literal <}CssMetaData{@literal <}? extends Node, ?{@literal >}{@literal >} temp =
 *         new ArrayList{@literal <}CssMetaData{@literal <}? extends Node, ?{@literal >}{@literal >}(Control.getClassCssMetaData());
 *     temp.add(GAP_META_DATA);
 *     cssMetaDataList = Collections.unmodifiableList(temp);
 * }
 *
 * public static List{@literal <}CssMetaData{@literal <}? extends Node, ?{@literal >}{@literal >} getClassCssMetaData() {
 *     return cssMetaDataList;
 * }
 *
 * {@literal @}Override
 * public List{@literal <}CssMetaData{@literal <}? extends Node, ?{@literal >}{@literal >} getCssMetaData() {
 *     return getClassCssMetaData();
 * }
 * 
* @param The type of Styleable * @param The type into which the parsed value is converted. * @since JavaFX 8.0 * @see javafx.css.StyleablePropertyFactory */ public abstract class CssMetaData { /** * Set the value of the corresponding property on the given Node. * @param styleable The Styleable on which the property value is being set * @param value The value to which the property is set * @param origin the origin * @deprecated This method is no longer called from CSS code. * Use {@link StyleableProperty#applyStyle(javafx.css.StyleOrigin, java.lang.Object)} */ @Deprecated(since="8") public void set(S styleable, V value, StyleOrigin origin) { final StyleableProperty styleableProperty = getStyleableProperty(styleable); final StyleOrigin currentOrigin = styleableProperty.getStyleOrigin(); final V currentValue = styleableProperty.getValue(); // RT-21185: Only apply the style if something has changed. if ((currentOrigin != origin) || (currentValue != null ? currentValue.equals(value) == false : value != null)) { styleableProperty.applyStyle(origin, value); } } /** * Check to see if the corresponding property on the given Node is * settable. This method is called before any styles are looked up for the * given property. It is abstract so that the code can check if the property * is settable without expanding the property. Generally, the property is * settable if it is not null or is not bound. * * @param styleable The Styleable on which the property value is being set * @return true if the property can be set. */ public abstract boolean isSettable(S styleable); /** * Return the corresponding {@link StyleableProperty} for the given Node. * Note that calling this method will cause the property to be expanded. * @param styleable The Styleable for which the property is returned * @return The StyleableProperty corresponding to this CssMetaData for the * given Styleable */ public abstract StyleableProperty getStyleableProperty(S styleable); private final String property; /** * @return the CSS property name */ public final String getProperty() { return property; } private final StyleConverter converter; /** * @return The CSS converter that handles conversion from a CSS value to a Java Object */ public final StyleConverter getConverter() { return converter; } private final V initialValue; /** * The initial value of a CssMetaData corresponds to the default * value of the StyleableProperty in code. * For example, the default value of Shape.fill is Color.BLACK and the * initialValue of Shape.StyleableProperties.FILL is also Color.BLACK. *

* There may be exceptions to this, however. The initialValue may depend * on the state of the Node. A ScrollBar has a default orientation of * horizontal. If the ScrollBar is vertical, however, this method should * return Orientation.VERTICAL. Otherwise, a vertical ScrollBar would be * incorrectly set to a horizontal ScrollBar when the initial value is * applied. * @param styleable the styleable * @return The initial value of the property, possibly null */ public V getInitialValue(S styleable) { return initialValue; } private final List> subProperties; /** * The sub-properties refers to the constituent properties of this property, * if any. For example, "-fx-font-weight" is sub-property of "-fx-font". * @return the list of sub-properties */ public final List> getSubProperties() { return subProperties; } private final boolean inherits; /** * If true, the value of this property is the same as * the parent's computed value of this property. * @return false by default unless inherits is true * @see CSS Inheritance */ public final boolean isInherits() { return inherits; } /** * Construct a CssMetaData with the given parameters and no sub-properties. * @param property the CSS property * @param converter the StyleConverter used to convert the CSS parsed value to a Java object. * @param initialValue The initial or default value of the corresponding StyleableProperty * @param inherits true if this property uses CSS inheritance * @param subProperties the sub-properties of this property. For example, * the -fx-font property has the sub-properties -fx-font-family, * -fx-font-size, -fx-font-weight, and -fx-font-style. */ protected CssMetaData( final String property, final StyleConverter converter, final V initialValue, boolean inherits, final List> subProperties) { this.property = property; this.converter = converter; this.initialValue = initialValue; this.inherits = inherits; this.subProperties = subProperties != null ? Collections.unmodifiableList(subProperties) : null; if (this.property == null || this.converter == null) { throw new IllegalArgumentException("neither property nor converter can be null"); } } /** * Construct a CssMetaData with the given parameters and no sub-properties. * @param property the CSS property * @param converter the StyleConverter used to convert the CSS parsed value to a Java object. * @param initialValue The initial or default value of the corresponding StyleableProperty * @param inherits true if this property uses CSS inheritance */ protected CssMetaData( final String property, final StyleConverter converter, final V initialValue, boolean inherits) { this(property, converter, initialValue, inherits, null); } /** * Construct a CssMetaData with the given parameters, inherit set to * false and no sub-properties. * @param property the CSS property * @param converter the StyleConverter used to convert the CSS parsed value to a Java object. * @param initialValue The initial or default value of the corresponding StyleableProperty */ protected CssMetaData( final String property, final StyleConverter converter, final V initialValue) { this(property, converter, initialValue, false, null); } /** * Construct a CssMetaData with the given parameters, initialValue is * null, inherit is set to false, and no sub-properties. * @param property the CSS property * @param converter the StyleConverter used to convert the CSS parsed value to a Java object. */ protected CssMetaData( final String property, final StyleConverter converter) { this(property, converter, null, false, null); } /** * Two CssMetaData objects are considered to be equal if their {@link #getProperty() property} values are equal. * @return true if the obj is equaled, false otherwise */ @Override public boolean equals(Object obj) { if (obj == null) { return false; } if (getClass() != obj.getClass()) { return false; } final CssMetaData other = (CssMetaData) obj; if ((this.property == null) ? (other.property != null) : !this.property.equals(other.property)) { return false; } return true; } @Override public int hashCode() { int hash = 3; hash = 19 * hash + (this.property != null ? this.property.hashCode() : 0); return hash; } @Override public String toString() { return new StringBuilder("CSSProperty {") .append("property: ").append(property) .append(", converter: ").append(converter.toString()) .append(", initalValue: ").append(String.valueOf(initialValue)) .append(", inherits: ").append(inherits) .append(", subProperties: ").append( (subProperties != null) ? subProperties.toString() : "[]") .append("}").toString(); } }





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