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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one or more
3    * contributor license agreements.  See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * The ASF licenses this file to You under the Apache License, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License.  You may obtain a copy of the License at
8    *
9    *      http://www.apache.org/licenses/LICENSE-2.0
10   *
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the License for the specific language governing permissions and
15   * limitations under the License.
16   */
17  
18  package org.apache.commons.lang3.mutable;
19  
20  import java.io.Serializable;
21  
22  import org.apache.commons.lang3.BooleanUtils;
23  
24  /**
25   * A mutable {@code boolean} wrapper.
26   * <p>
27   * Note that as MutableBoolean does not extend Boolean, it is not treated by String.format as a Boolean parameter.
28   * </p>
29   *
30   * @see Boolean
31   * @since 2.2
32   */
33  public class MutableBoolean implements Mutable<Boolean>, Serializable, Comparable<MutableBoolean> {
34  
35      /**
36       * Required for serialization support.
37       *
38       * @see java.io.Serializable
39       */
40      private static final long serialVersionUID = -4830728138360036487L;
41  
42      /** The mutable value. */
43      private boolean value;
44  
45      /**
46       * Constructs a new MutableBoolean with the default value of false.
47       */
48      public MutableBoolean() {
49      }
50  
51      /**
52       * Constructs a new MutableBoolean with the specified value.
53       *
54       * @param value  the initial value to store
55       */
56      public MutableBoolean(final boolean value) {
57          this.value = value;
58      }
59  
60      /**
61       * Constructs a new MutableBoolean with the specified value.
62       *
63       * @param value  the initial value to store, not null
64       * @throws NullPointerException if the object is null
65       */
66      public MutableBoolean(final Boolean value) {
67          this.value = value.booleanValue();
68      }
69  
70      /**
71       * Returns the value of this MutableBoolean as a boolean.
72       *
73       * @return the boolean value represented by this object.
74       */
75      public boolean booleanValue() {
76          return value;
77      }
78  
79      /**
80       * Compares this mutable to another in ascending order.
81       *
82       * @param other  the other mutable to compare to, not null
83       * @return negative if this is less, zero if equal, positive if greater
84       *  where false is less than true
85       */
86      @Override
87      public int compareTo(final MutableBoolean other) {
88          return BooleanUtils.compare(this.value, other.value);
89      }
90  
91      /**
92       * Compares this object to the specified object. The result is {@code true} if and only if the argument is
93       * not {@code null} and is an {@link MutableBoolean} object that contains the same
94       * {@code boolean} value as this object.
95       *
96       * @param obj  the object to compare with, null returns false
97       * @return {@code true} if the objects are the same; {@code false} otherwise.
98       */
99      @Override
100     public boolean equals(final Object obj) {
101         if (obj instanceof MutableBoolean) {
102             return value == ((MutableBoolean) obj).booleanValue();
103         }
104         return false;
105     }
106 
107     /**
108      * Gets the value as a Boolean instance.
109      *
110      * @return the value as a Boolean, never null
111      */
112     @Override
113     public Boolean getValue() {
114         return Boolean.valueOf(this.value);
115     }
116 
117     /**
118      * Returns a suitable hash code for this mutable.
119      *
120      * @return the hash code returned by {@code Boolean.TRUE} or {@code Boolean.FALSE}
121      */
122     @Override
123     public int hashCode() {
124         return value ? Boolean.TRUE.hashCode() : Boolean.FALSE.hashCode();
125     }
126 
127     /**
128      * Checks if the current value is {@code false}.
129      *
130      * @return {@code true} if the current value is {@code false}
131      * @since 2.5
132      */
133     public boolean isFalse() {
134         return !value;
135     }
136 
137     /**
138      * Checks if the current value is {@code true}.
139      *
140      * @return {@code true} if the current value is {@code true}
141      * @since 2.5
142      */
143     public boolean isTrue() {
144         return value;
145     }
146 
147     /**
148      * Sets the value to false.
149      *
150      * @since 3.3
151      */
152     public void setFalse() {
153         this.value = false;
154     }
155 
156     /**
157      * Sets the value to true.
158      *
159      * @since 3.3
160      */
161     public void setTrue() {
162         this.value = true;
163     }
164 
165     /**
166      * Sets the value.
167      *
168      * @param value  the value to set
169      */
170     public void setValue(final boolean value) {
171         this.value = value;
172     }
173 
174     /**
175      * Sets the value from any Boolean instance.
176      *
177      * @param value  the value to set, not null
178      * @throws NullPointerException if the object is null
179      */
180     @Override
181     public void setValue(final Boolean value) {
182         this.value = value.booleanValue();
183     }
184 
185     /**
186      * Gets this mutable as an instance of Boolean.
187      *
188      * @return a Boolean instance containing the value from this mutable, never null
189      * @since 2.5
190      */
191     public Boolean toBoolean() {
192         return Boolean.valueOf(booleanValue());
193     }
194 
195     /**
196      * Returns the String value of this mutable.
197      *
198      * @return the mutable value as a string
199      */
200     @Override
201     public String toString() {
202         return String.valueOf(value);
203     }
204 
205 }