/*
* GeoTools - The Open Source Java GIS Toolkit
* http://geotools.org
*
* (C) 2004-2008, Open Source Geospatial Foundation (OSGeo)
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation;
* version 2.1 of the License.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*/
package org.geotools.util;
import java.io.Serializable;
import java.util.Map;
import org.geotools.resources.Classes;
/**
* A default implementation of {@link java.util.Map.Entry} which map an arbitrary
* key-value pairs. This entry is immutable by default.
*
* @param <K> The class of key elements.
* @param <V> The class of value elements.
*
* @since 2.1
* @source $URL$
* @version $Id$
* @author Martin Desruisseaux (IRD)
*
* @todo This class will be removed when we will be allowed to compile for JSE 1.6, since a
* default map entry implementation is provided there.
*/
public class MapEntry<K,V> implements Map.Entry<K,V>, Serializable {
/**
* For cross-version compatibility.
*/
private static final long serialVersionUID = 8627698052283756776L;
/**
* The key.
*/
private final K key;
/**
* The value.
*/
private final V value;
/**
* Creates a new map entry with the specified key-value pair.
*
* @param key The key.
* @param value The value.
*/
public MapEntry(final K key, final V value) {
this.key = key;
this.value = value;
}
/**
* Returns the key corresponding to this entry.
*/
public K getKey() {
return key;
}
/**
* Returns the value corresponding to this entry.
*/
public V getValue() {
return value;
}
/**
* Replaces the value corresponding to this entry with the specified
* value (optional operation). The default implementation throws an
* {@link UnsupportedOperationException}.
*/
public V setValue(final V value) {
throw new UnsupportedOperationException();
}
/**
* Compares the specified object with this entry for equality.
*
* @param object The object to compare with this entry for equality.
*/
@Override
public boolean equals(final Object object) {
if (object instanceof Map.Entry) {
final Map.Entry that = (Map.Entry) object;
return Utilities.equals(this.getKey(), that.getKey()) &&
Utilities.equals(this.getValue(), that.getValue());
}
return false;
}
/**
* Returns the hash code value for this map entry
*/
@Override
public int hashCode() {
int code = 0;
if (key != null) code = key.hashCode();
if (value != null) code ^= value.hashCode();
return code;
}
/**
* Returns a string representation of this entry.
*/
@Override
public String toString() {
return Classes.getShortClassName(this) + "[key=" + key + ", value=" + value + ']';
}
}