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;
  
  /**
   * A mutable <code>long</code> wrapper.
   * 
   * @see Long
   * @since 2.1
   * @version $Id: MutableLong.java 437554 2006-08-28 06:21:41Z bayard $
   */
  public class MutableLong extends Number implements Comparable, Mutable {
  
      /**
       * Required for serialization support.
       * 
       * @see java.io.Serializable
       */
      private static final long serialVersionUID = 62986528375L;
  
      /** The mutable value. */
      private long value;
  
      /**
       * Constructs a new MutableLong with the default value of zero.
       */
      public MutableLong() {
          super();
      }
  
      /**
       * Constructs a new MutableLong with the specified value.
       * 
       * @param value
       *            a value.
       */
      public MutableLong(long value) {
          super();
          this.value = value;
      }
  
      /**
       * Constructs a new MutableLong with the specified value.
       * 
       * @param value
       *            a value.
       * @throws NullPointerException
       *             if the object is null
       */
      public MutableLong(Number value) {
          super();
          this.value = value.longValue();
      }
  
      //-----------------------------------------------------------------------
      /**
       * Gets the value as a Long instance.
       * 
       * @return the value as a Long
       */
      public Object getValue() {
          return new Long(this.value);
      }
  
      /**
       * Sets the value.
       * 
       * @param value
       *            the value to set
       */
      public void setValue(long value) {
          this.value = value;
      }
  
      /**
       * Sets the value from any Number instance.
       * 
       * @param value
       *            the value to set
       * @throws NullPointerException
       *             if the object is null
       * @throws ClassCastException
       *             if the type is not a {@link Number}
       */
      public void setValue(Object value) {
          setValue(((Number) value).longValue());
      }
  
      //-----------------------------------------------------------------------
      /**
       * Increments the value.
       *
       * @since Commons Lang 2.2
       */
      public void increment() {
          value++;
      }
  
      /**
       * Decrements the value.
       *
       * @since Commons Lang 2.2
       */
      public void decrement() {
          value--;
      }
  
      //-----------------------------------------------------------------------
      /**
       * Adds a value.
       * 
       * @param operand
       *            the value to add
       *
       * @since Commons Lang 2.2
       */
      public void add(long operand) {
          this.value += operand;
      }
  
      /**
       * Adds a value.
       * 
       * @param operand
       *            the value to add
       * @throws NullPointerException
       *             if the object is null
       *
       * @since Commons Lang 2.2
       */
      public void add(Number operand) {
          this.value += operand.longValue();
      }
  
      /**
       * Subtracts a value.
       * 
       * @param operand
       *            the value to add
       *
       * @since Commons Lang 2.2
       */
      public void subtract(long operand) {
          this.value -= operand;
      }
  
      /**
       * Subtracts a value.
       * 
       * @param operand
       *            the value to add
       * @throws NullPointerException
       *             if the object is null
       *
       * @since Commons Lang 2.2
       */
      public void subtract(Number operand) {
          this.value -= operand.longValue();
      }
  
      //-----------------------------------------------------------------------
      // shortValue and bytValue rely on Number implementation
      /**
       * Returns the value of this MutableLong as a int.
       *
       * @return the numeric value represented by this object after conversion to type int.
       */
      public int intValue() {
          return (int) value;
      }
  
      /**
       * Returns the value of this MutableLong as a long.
       *
       * @return the numeric value represented by this object after conversion to type long.
       */
      public long longValue() {
          return value;
      }
  
      /**
       * Returns the value of this MutableLong as a float.
       *
       * @return the numeric value represented by this object after conversion to type float.
       */
      public float floatValue() {
          return value;
      }
  
      /**
       * Returns the value of this MutableLong as a double.
       *
       * @return the numeric value represented by this object after conversion to type double.
       */
      public double doubleValue() {
          return value;
      }
  
      //-----------------------------------------------------------------------
      /**
       * Gets this mutable as an instance of Long.
       *
       * @return a Long instance containing the value from this mutable
       */
      public Long toLong() {
          return new Long(longValue());
      }
  
      //-----------------------------------------------------------------------
      /**
       * Compares this object against the specified object. The result is <code>true</code> if and only if the argument
       * is not <code>null</code> and is a <code>MutableLong</code> object that contains the same <code>long</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 MutableLong) {
              return value == ((MutableLong) obj).longValue();
          }
          return false;
      }
  
      /**
       * Returns a suitable hashcode for this mutable.
       * 
       * @return a suitable hashcode
       */
      public int hashCode() {
          return (int) (value ^ (value >>> 32));
      }
  
      /**
       * Compares this mutable to another in ascending order.
       * 
       * @param obj
       *            the mutable to compare to
       * @return negative if this is less, zero if equal, positive if greater
       * @throws ClassCastException if the argument is not a MutableLong
       */
      public int compareTo(Object obj) {
          MutableLong other = (MutableLong) obj;
          long anotherVal = other.value;
          return value < anotherVal ? -1 : (value == anotherVal ? 0 : 1);
      }
  
      /**
       * Returns the String value of this mutable.
       * 
       * @return the mutable value as a string
       */
      public String toString() {
          return String.valueOf(value);
      }
  
  }
  