code: /*
   * Licensed to the Apache Software Foundation (ASF) under one or more
   * contributor license agreements.  See the NOTICE file distributed with
   * this work for additional information regarding copyright ownership.
   * The ASF licenses this file to You under the Apache License, Version 2.0
   * (the "License"); you may not use this file except in compliance with
   * the License.  You may obtain a copy of the License at
   * 
   *      http://www.apache.org/licenses/LICENSE-2.0
   * 
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  package org.apache.commons.lang.mutable;
  
  import java.io.Serializable;
  
  import org.apache.commons.lang.BooleanUtils;
  
  /**
   * A mutable <code>boolean</code> wrapper.
   * 
   * @see Boolean
   * @since 2.2
   * @author Apache Software Foundation
   * @version $Id: MutableBoolean.java 491052 2006-12-29 17:16:37Z scolebourne $
   */
  public class MutableBoolean implements Mutable, Serializable, Comparable {
  
      /**
       * Required for serialization support.
       * 
       * @see java.io.Serializable
       */
      private static final long serialVersionUID = -4830728138360036487L;
  
      /** The mutable value. */
      private boolean value;
  
      /**
       * Constructs a new MutableBoolean with the default value of false.
       */
      public MutableBoolean() {
          super();
      }
  
      /**
       * Constructs a new MutableBoolean with the specified value.
       * 
       * @param value
       *            a value.
       */
      public MutableBoolean(boolean value) {
          super();
          this.value = value;
      }
  
      /**
       * Constructs a new MutableBoolean with the specified value.
       * 
       * @param value
       *            a value.
       * @throws NullPointerException
       *             if the object is null
       */
      public MutableBoolean(Boolean value) {
          super();
          this.value = value.booleanValue();
      }
  
      // -----------------------------------------------------------------------
      /**
       * Returns the value of this MutableBoolean as a boolean.
       * 
       * @return the boolean value represented by this object.
       */
      public boolean booleanValue() {
          return value;
      }
  
      /**
       * Compares this mutable to another in ascending order.
       * 
       * @param obj
       *            the mutable to compare to
       * @return zero if this object represents the same boolean value as the argument; a positive value if this object
       *         represents true and the argument represents false; and a negative value if this object represents false
       *         and the argument represents true
       * @throws ClassCastException
       *             if the argument is not a MutableInt
       */
      public int compareTo(Object obj) {
          MutableBoolean other = (MutableBoolean) obj;
          boolean anotherVal = other.value;
          return value == anotherVal ? 0 : (value ? 1 : -1);
      }
  
      // -----------------------------------------------------------------------
      /**
       * Compares this object to the specified object. The result is <code>true</code> if and only if the argument is
       * not <code>null</code> and is an <code>MutableBoolean</code> object that contains the same
       * <code>boolean</code> value as this object.
       * 
       * @param obj
       *            the object to compare with.
       * @return <code>true</code> if the objects are the same; <code>false</code> otherwise.
       */
      public boolean equals(Object obj) {
          if (obj instanceof MutableBoolean) {
              return value == ((MutableBoolean) obj).booleanValue();
          }
          return false;
      }
  
      // -----------------------------------------------------------------------
      /**
       * Gets the value as a Boolean instance.
       * 
       * @return the value as a Boolean
       */
      public Object getValue() {
          return BooleanUtils.toBooleanObject(this.value);
      }
  
      /**
       * Returns a suitable hashcode for this mutable.
       * 
       * @return the integer <code>1231</code> if this object represents <code>true</code>; returns the integer
       *         <code>1237</code> if this object represents <code>false</code>.
       */
      public int hashCode() {
          return value ? Boolean.TRUE.hashCode() : Boolean.FALSE.hashCode();
      }
  
      /**
       * Sets the value.
       * 
       * @param value
       *            the value to set
       */
      public void setValue(boolean value) {
          this.value = value;
      }
  
      /**
       * Sets the value from any Boolean instance.
       * 
       * @param value
       *            the value to set
       * @throws NullPointerException
       *             if the object is null
       * @throws ClassCastException
       *             if the type is not a {@link Boolean}
       */
      public void setValue(Object value) {
          setValue(((Boolean) value).booleanValue());
      }
  
      /**
       * Returns the String value of this mutable.
       * 
       * @return the mutable value as a string
       */
      public String toString() {
          return String.valueOf(value);
      }
  
  }
  