content: /* 
   * Kodkod -- Copyright (c) 2005-present, Emina Torlak
   *
   * Permission is hereby granted, free of charge, to any person obtaining a copy
   * of this software and associated documentation files (the "Software"), to deal
   * in the Software without restriction, including without limitation the rights
   * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
   * copies of the Software, and to permit persons to whom the Software is
   * furnished to do so, subject to the following conditions:
   *
   * The above copyright notice and this permission notice shall be included in
   * all copies or substantial portions of the Software.
   *
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
   * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
   * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
   * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
   * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
   * THE SOFTWARE.
   */
  package kodkod.util.ints;
  
  /**
   * A mutable IndexedEntry.  This class provides
   * various convience method for changing the entry state.
   * @author Emina Torlak
   */
  class EntryView<V> implements IndexedEntry<V> {
  	private int index;
  	private V value;
  	
  	/**
  	 * Constructs a new entry view with the given index and value.
  	 * @ensures this.index' = index and this.value' = value
  	 */
  	EntryView(int index, V value) {
  		this.index = index;
  		this.value = value;
  	}
  	
  	
  	/**
  	 * Sets this.index to the given index, 
  	 * and returns the old index.
  	 * @ensures this.index' = newIndex
  	 * @return this.index
  	 */
  	int setIndex(int newIndex) {
  		final int oldIndex = this.index;
  		this.index = newIndex;
  		return oldIndex;
  	}
  	
  	/**
  	 * Sets this.value to the given value, 
  	 * and returns the old value.
  	 * @ensures this.value' = newValue
  	 * @return this.value
  	 */
  	V setValue(V newValue) {
  		final V oldValue = this.value;
  		this.value = newValue;
  		return oldValue;
  	}
  	
  	/**
  	 * Sets this.index and this.value to the given
  	 * index and value, and returns this.
  	 * @ensures this.index' = newIndex && this.value' = newValue
  	 * @return this
  	 */
  	IndexedEntry<V> setView(int newIndex, V newValue) {
  		this.index = newIndex;
  		this.value = newValue;
  		return this;
  	}
  	
  	/**
  	 * Sets this.index to the given
  	 * index, and returns this.
  	 * @ensures this.index' = newIndex 
  	 * @return this
  	 */
  	IndexedEntry<V> setIndexView(int newIndex) {
  		this.index = newIndex;
  		return this;
  	}
  
  	/**
  	 * Sets this.value to the given
  	 * value, and returns this.
  	 * @ensures this.value' = newValue
  	 * @return this
  	 */
  	IndexedEntry<V> setValueView(V newValue) {
  		this.value = newValue;
  		return this;
  	}
  	
  	/**
  	 * @see kodkod.util.ints.IndexedEntry#index()
  	 */
  	public int index() {
  		return index;
  	}
  
  	/**
  	 * @see kodkod.util.ints.IndexedEntry#value()
  	 */
  	public V value() {
  		return value;
  	}
  
  	/**
  	 * @see java.lang.Object#toString()
  	 */
  	public final String toString() {
  		return index + "=" + value;
  	}
  	
  	/**
  	 * @see java.lang.Object#equals(java.lang.Object)
  	 */
  	public final boolean equals(Object o) {
  		if (o==this) return true;
  		if (!(o instanceof IndexedEntry)) return false;
  		return AbstractSparseSequence.equal(this, (IndexedEntry<?>)o);
  	}
  	
  	/**
  	 * @see java.lang.Object#hashCode()
  	 */
  	public final int hashCode() {
  		return AbstractSparseSequence.hashCode(this);
  	}	
  }
  