001 /*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements. See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License. You may obtain a copy of the License at
008 *
009 * http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017
018 package org.apache.commons.lang.mutable;
019
020 import java.io.Serializable;
021
022 import org.apache.commons.lang.BooleanUtils;
023
024 /**
025 * A mutable <code>boolean</code> wrapper.
026 *
027 * @see Boolean
028 * @since 2.2
029 * @author Apache Software Foundation
030 * @version $Id: MutableBoolean.java 905707 2010-02-02 16:59:59Z niallp $
031 */
032 public class MutableBoolean implements Mutable, Serializable, Comparable {
033
034 /**
035 * Required for serialization support.
036 *
037 * @see java.io.Serializable
038 */
039 private static final long serialVersionUID = -4830728138360036487L;
040
041 /** The mutable value. */
042 private boolean value;
043
044 /**
045 * Constructs a new MutableBoolean with the default value of false.
046 */
047 public MutableBoolean() {
048 super();
049 }
050
051 /**
052 * Constructs a new MutableBoolean with the specified value.
053 *
054 * @param value the initial value to store
055 */
056 public MutableBoolean(boolean value) {
057 super();
058 this.value = value;
059 }
060
061 /**
062 * Constructs a new MutableBoolean with the specified value.
063 *
064 * @param value the initial value to store, not null
065 * @throws NullPointerException if the object is null
066 */
067 public MutableBoolean(Boolean value) {
068 super();
069 this.value = value.booleanValue();
070 }
071
072 //-----------------------------------------------------------------------
073 /**
074 * Gets the value as a Boolean instance.
075 *
076 * @return the value as a Boolean, never null
077 */
078 public Object getValue() {
079 return BooleanUtils.toBooleanObject(this.value);
080 }
081
082 /**
083 * Sets the value.
084 *
085 * @param value the value to set
086 */
087 public void setValue(boolean value) {
088 this.value = value;
089 }
090
091 /**
092 * Sets the value from any Boolean instance.
093 *
094 * @param value the value to set, not null
095 * @throws NullPointerException if the object is null
096 */
097 public void setValue(Object value) {
098 setValue(((Boolean) value).booleanValue());
099 }
100
101 //-----------------------------------------------------------------------
102 /**
103 * Checks if the current value is <code>true</code>.
104 *
105 * @return <code>true</code> if the current value is <code>true</code>
106 * @since 2.5
107 */
108 public boolean isTrue() {
109 return value == true;
110 }
111
112 /**
113 * Checks if the current value is <code>false</code>.
114 *
115 * @return <code>true</code> if the current value is <code>false</code>
116 * @since 2.5
117 */
118 public boolean isFalse() {
119 return value == false;
120 }
121
122 //-----------------------------------------------------------------------
123 /**
124 * Returns the value of this MutableBoolean as a boolean.
125 *
126 * @return the boolean value represented by this object.
127 */
128 public boolean booleanValue() {
129 return value;
130 }
131
132 //-----------------------------------------------------------------------
133 /**
134 * Gets this mutable as an instance of Boolean.
135 *
136 * @return a Boolean instance containing the value from this mutable, never null
137 * @since 2.5
138 */
139 public Boolean toBoolean() {
140 return BooleanUtils.toBooleanObject(this.value);
141 }
142
143 //-----------------------------------------------------------------------
144 /**
145 * Compares this object to the specified object. The result is <code>true</code> if and only if the argument is
146 * not <code>null</code> and is an <code>MutableBoolean</code> object that contains the same
147 * <code>boolean</code> value as this object.
148 *
149 * @param obj the object to compare with, null returns false
150 * @return <code>true</code> if the objects are the same; <code>false</code> otherwise.
151 */
152 public boolean equals(Object obj) {
153 if (obj instanceof MutableBoolean) {
154 return value == ((MutableBoolean) obj).booleanValue();
155 }
156 return false;
157 }
158
159 /**
160 * Returns a suitable hash code for this mutable.
161 *
162 * @return the hash code returned by <code>Boolean.TRUE</code> or <code>Boolean.FALSE</code>
163 */
164 public int hashCode() {
165 return value ? Boolean.TRUE.hashCode() : Boolean.FALSE.hashCode();
166 }
167
168 //-----------------------------------------------------------------------
169 /**
170 * Compares this mutable to another in ascending order.
171 *
172 * @param obj the other mutable to compare to, not null
173 * @return negative if this is less, zero if equal, positive if greater
174 * where false is less than true
175 */
176 public int compareTo(Object obj) {
177 MutableBoolean other = (MutableBoolean) obj;
178 boolean anotherVal = other.value;
179 return value == anotherVal ? 0 : (value ? 1 : -1);
180 }
181
182 //-----------------------------------------------------------------------
183 /**
184 * Returns the String value of this mutable.
185 *
186 * @return the mutable value as a string
187 */
188 public String toString() {
189 return String.valueOf(value);
190 }
191
192 }