    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    }