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.lang3.mutable;
019    
020    import java.io.Serializable;
021    
022    /**
023     * A mutable <code>boolean</code> wrapper.
024     * 
025     * @see Boolean
026     * @since 2.2
027     * @author Apache Software Foundation
028     * @version $Id: MutableBoolean.java 916081 2010-02-25 01:28:13Z niallp $
029     */
030    public class MutableBoolean implements Mutable<Boolean>, Serializable, Comparable<MutableBoolean> {
031    
032        /**
033         * Required for serialization support.
034         * 
035         * @see java.io.Serializable
036         */
037        private static final long serialVersionUID = -4830728138360036487L;
038    
039        /** The mutable value. */
040        private boolean value;
041    
042        /**
043         * Constructs a new MutableBoolean with the default value of false.
044         */
045        public MutableBoolean() {
046            super();
047        }
048    
049        /**
050         * Constructs a new MutableBoolean with the specified value.
051         * 
052         * @param value  the initial value to store
053         */
054        public MutableBoolean(boolean value) {
055            super();
056            this.value = value;
057        }
058    
059        /**
060         * Constructs a new MutableBoolean with the specified value.
061         * 
062         * @param value  the initial value to store, not null
063         * @throws NullPointerException if the object is null
064         */
065        public MutableBoolean(Boolean value) {
066            super();
067            this.value = value.booleanValue();
068        }
069    
070        //-----------------------------------------------------------------------
071        /**
072         * Gets the value as a Boolean instance.
073         * 
074         * @return the value as a Boolean, never null
075         */
076        public Boolean getValue() {
077            return Boolean.valueOf(this.value);
078        }
079    
080        /**
081         * Sets the value.
082         * 
083         * @param value  the value to set
084         */
085        public void setValue(boolean value) {
086            this.value = value;
087        }
088    
089        /**
090         * Sets the value from any Boolean instance.
091         * 
092         * @param value  the value to set, not null
093         * @throws NullPointerException if the object is null
094         */
095        public void setValue(Boolean value) {
096            this.value = value.booleanValue();
097        }
098    
099        //-----------------------------------------------------------------------
100        /**
101         * Checks if the current value is <code>true</code>.
102         * 
103         * @return <code>true</code> if the current value is <code>true</code>
104         * @since 2.5
105         */
106        public boolean isTrue() {
107            return value == true;
108        }
109    
110        /**
111         * Checks if the current value is <code>false</code>.
112         * 
113         * @return <code>true</code> if the current value is <code>false</code>
114         * @since 2.5
115         */
116        public boolean isFalse() {
117            return value == false;
118        }
119    
120        //-----------------------------------------------------------------------
121        /**
122         * Returns the value of this MutableBoolean as a boolean.
123         * 
124         * @return the boolean value represented by this object.
125         */
126        public boolean booleanValue() {
127            return value;
128        }
129    
130        //-----------------------------------------------------------------------
131        /**
132         * Gets this mutable as an instance of Boolean.
133         *
134         * @return a Boolean instance containing the value from this mutable, never null
135         * @since 2.5
136         */
137        public Boolean toBoolean() {
138            return Boolean.valueOf(booleanValue());
139        }
140    
141        //-----------------------------------------------------------------------
142        /**
143         * Compares this object to the specified object. The result is <code>true</code> if and only if the argument is
144         * not <code>null</code> and is an <code>MutableBoolean</code> object that contains the same
145         * <code>boolean</code> value as this object.
146         * 
147         * @param obj  the object to compare with, null returns false
148         * @return <code>true</code> if the objects are the same; <code>false</code> otherwise.
149         */
150        @Override
151        public boolean equals(Object obj) {
152            if (obj instanceof MutableBoolean) {
153                return value == ((MutableBoolean) obj).booleanValue();
154            }
155            return false;
156        }
157    
158        /**
159         * Returns a suitable hash code for this mutable.
160         * 
161         * @return the hash code returned by <code>Boolean.TRUE</code> or <code>Boolean.FALSE</code>
162         */
163        @Override
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 other  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(MutableBoolean other) {
177            boolean anotherVal = other.value;
178            return value == anotherVal ? 0 : (value ? 1 : -1);
179        }
180    
181        //-----------------------------------------------------------------------
182        /**
183         * Returns the String value of this mutable.
184         * 
185         * @return the mutable value as a string
186         */
187        @Override
188        public String toString() {
189            return String.valueOf(value);
190        }
191    
192    }