java.util

Interface Map.Entry<K,V>

public static interface Map.Entry<K,V>

A map entry (key-value pair). The Map.entrySet() method returns a set view of these objects; there is no other valid way to come across them. These objects are only valid for the duration of an iteration; in other words, if you mess with one after modifying the map, you are asking for undefined behavior.
Since:
1.2
See Also:
Map, Map.entrySet()

Method Summary

boolean
equals(Object o)
Compares the specified object with this entry.
K
getKey()
Get the key corresponding to this entry.
V
getValue()
Get the value corresponding to this entry.
int
hashCode()
Returns the hash code of the entry.
V
setValue(V value)
Replaces the value with the specified object (optional operation).

Method Details

equals

public boolean equals(Object o)
Compares the specified object with this entry. Returns true only if the object is a mapping of identical key and value. In other words, this must be:

(o instanceof Map.Entry)
&& (getKey() == null ? ((Map.Entry) o).getKey() == null
: getKey().equals(((Map.Entry) o).getKey()))
&& (getValue() == null ? ((Map.Entry) o).getValue() == null
: getValue().equals(((Map.Entry) o).getValue()))
Overrides:
equals in interface Object
Parameters:
o - the object to compare
Returns:
true if it is equal

getKey

public K getKey()
Get the key corresponding to this entry.
Returns:
the key

getValue

public V getValue()
Get the value corresponding to this entry. If you already called Iterator.remove(), this is undefined.
Returns:
the value

hashCode

public int hashCode()
Returns the hash code of the entry. This is defined as the exclusive-or of the hashcodes of the key and value (using 0 for null). In other words, this must be:

(getKey() == null ? 0 : getKey().hashCode())
^ (getValue() == null ? 0 : getValue().hashCode())
Overrides:
hashCode in interface Object
Returns:
the hash code

setValue

public V setValue(V value)
Replaces the value with the specified object (optional operation). This writes through to the map, and is undefined if you already called Iterator.remove().
Parameters:
value - the new value to store
Returns:
the old value
Throws:
UnsupportedOperationException - if the operation is not supported
ClassCastException - if the value is of the wrong type
IllegalArgumentException - if something about the value prevents it from existing in this map
NullPointerException - if the map forbids null values

Map.java: interface Map -- An object that maps keys to values interface Map.Entry -- an Entry in a Map Copyright (C) 1998, 2001, 2004, 2005 Free Software Foundation, Inc. This file is part of GNU Classpath. GNU Classpath is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2, or (at your option) any later version. GNU Classpath 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 General Public License for more details. You should have received a copy of the GNU General Public License along with GNU Classpath; see the file COPYING. If not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. Linking this library statically or dynamically with other modules is making a combined work based on this library. Thus, the terms and conditions of the GNU General Public License cover the whole combination. As a special exception, the copyright holders of this library give you permission to link this library with independent modules to produce an executable, regardless of the license terms of these independent modules, and to copy and distribute the resulting executable under terms of your choice, provided that you also meet, for each linked independent module, the terms and conditions of the license of that module. An independent module is a module which is not derived from or based on this library. If you modify this library, you may extend this exception to your version of the library, but you are not obligated to do so. If you do not wish to do so, delete this exception statement from your version.