Spec-Zone .ru
спецификации, руководства, описания, API
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001/* 002 * Copyright (c) 2011, 2013, Oracle and/or its affiliates. All rights reserved. 003 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 004 * 005 * This code is free software; you can redistribute it and/or modify it 006 * under the terms of the GNU General Public License version 2 only, as 007 * published by the Free Software Foundation. Oracle designates this 008 * particular file as subject to the "Classpath" exception as provided 009 * by Oracle in the LICENSE file that accompanied this code. 010 * 011 * This code is distributed in the hope that it will be useful, but WITHOUT 012 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 013 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 014 * version 2 for more details (a copy is included in the LICENSE file that 015 * accompanied this code). 016 * 017 * You should have received a copy of the GNU General Public License version 018 * 2 along with this work; if not, write to the Free Software Foundation, 019 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 020 * 021 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 022 * or visit www.oracle.com if you need additional information or have any 023 * questions. 024 */ 025 026package javafx.beans.property; 027 028import javafx.beans.InvalidationListener; 029import javafx.beans.Observable; 030import javafx.beans.WeakInvalidationListener; 031import javafx.beans.binding.LongExpression; 032 033/** 034 * Super class for all readonly properties wrapping a {@code long}. 035 * 036 * @see javafx.beans.value.ObservableLongValue 037 * @see javafx.beans.binding.LongExpression 038 * @see ReadOnlyProperty 039 * 040 */ 041public abstract class ReadOnlyLongProperty extends LongExpression implements 042 ReadOnlyProperty<Number> { 043 044 /** 045 * The constructor of {@code ReadOnlyLongProperty}. 046 */ 047 public ReadOnlyLongProperty() { 048 } 049 050 /** 051 * Returns a string representation of this {@code ReadOnlyLongProperty} object. 052 * @return a string representation of this {@code ReadOnlyLongProperty} object. 053 */ 054 @Override 055 public String toString() { 056 final Object bean = getBean(); 057 final String name = getName(); 058 final StringBuilder result = new StringBuilder("ReadOnlyLongProperty ["); 059 if (bean != null) { 060 result.append("bean: ").append(bean).append(", "); 061 } 062 if ((name != null) && !name.equals("")) { 063 result.append("name: ").append(name).append(", "); 064 } 065 result.append("value: ").append(get()).append("]"); 066 return result.toString(); 067 } 068 069 /** 070 * Returns a {@code ReadOnlyLongProperty} that wraps a 071 * {@link javafx.beans.property.ReadOnlyProperty}. If the 072 * {@code ReadOnlyProperty} is already a {@code ReadOnlyLongProperty}, it 073 * will be returned. Otherwise a new 074 * {@code ReadOnlyLongProperty} is created that is bound to 075 * the {@code ReadOnlyProperty}. 076 * 077 * Note: null values will be interpreted as 0L 078 * 079 * @param property 080 * The source {@code ReadOnlyProperty} 081 * @return A {@code ReadOnlyLongProperty} that wraps the 082 * {@code ReadOnlyProperty} if necessary 083 * @throws NullPointerException 084 * if {@code value} is {@code null} 085 */ 086 public static <T extends Number> ReadOnlyLongProperty readOnlyLongProperty(final ReadOnlyProperty<T> property) { 087 if (property == null) { 088 throw new NullPointerException("Property cannot be null"); 089 } 090 091 return property instanceof ReadOnlyLongProperty ? (ReadOnlyLongProperty) property: 092 new ReadOnlyLongPropertyBase() { 093 private boolean valid = true; 094 private final InvalidationListener listener = new InvalidationListener() { 095 @Override 096 public void invalidated(Observable observable) { 097 if (valid) { 098 valid = false; 099 fireValueChangedEvent(); 100 } 101 } 102 }; 103 104 { 105 property.addListener(new WeakInvalidationListener(listener)); 106 } 107 108 @Override 109 public long get() { 110 valid = true; 111 final T value = property.getValue(); 112 return value == null ? 0L : value.longValue(); 113 } 114 115 @Override 116 public Object getBean() { 117 return null; // Virtual property, no bean 118 } 119 120 @Override 121 public String getName() { 122 return property.getName(); 123 } 124 }; 125 } 126 127 /** 128 * Creates a {@link javafx.beans.property.ReadOnlyObjectProperty} that holds the value 129 * of this {@code ReadOnlyLongProperty}. If the 130 * value of this {@code ReadOnlyLongProperty} changes, the value of the 131 * {@code ReadOnlyObjectProperty} will be updated automatically. 132 * 133 * @return the new {@code ReadOnlyObjectProperty} 134 */ 135 @Override 136 public ReadOnlyObjectProperty<Long> asObject() { 137 return new ReadOnlyObjectPropertyBase<Long>() { 138 139 private boolean valid = true; 140 private final InvalidationListener listener = new InvalidationListener() { 141 @Override 142 public void invalidated(Observable observable) { 143 if (valid) { 144 valid = false; 145 fireValueChangedEvent(); 146 } 147 } 148 }; 149 150 { 151 ReadOnlyLongProperty.this.addListener(new WeakInvalidationListener(listener)); 152 } 153 154 @Override 155 public Object getBean() { 156 return null; // Virtual property, does not exist on a bean 157 } 158 159 @Override 160 public String getName() { 161 return ReadOnlyLongProperty.this.getName(); 162 } 163 164 @Override 165 public Long get() { 166 valid = true; 167 return ReadOnlyLongProperty.this.getValue(); 168 } 169 }; 170 }; 171 172}