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java.util
interface: Map.Entry [javadoc | source]

All Known Implementing Classes:
    CheckedEntry, ParameterMapEntry

A map entry (key-value pair). The Map.entrySet method returns a collection-view of the map, whose elements are of this class. The only way to obtain a reference to a map entry is from the iterator of this collection-view. These Map.Entry objects are valid only for the duration of the iteration; more formally, the behavior of a map entry is undefined if the backing map has been modified after the entry was returned by the iterator, except through the setValue operation on the map entry.
Method from java.util.Map$Entry Summary:
equals,   getKey,   getValue,   hashCode,   setValue
Method from java.util.Map$Entry Detail:
 public boolean equals(Object o)
    Compares the specified object with this entry for equality.
Returns true if the given object is also a map entry and
the two entries represent the same mapping. More formally, two
entries e1 and e2 represent the same mapping
if
    (e1.getKey()==null ?
e2.getKey()==null : e1.getKey().equals(e2.getKey())) &&
(e1.getValue()==null ?
e2.getValue()==null : e1.getValue().equals(e2.getValue()))

    
This ensures that the equals method works properly across
different implementations of the Map.Entry interface.
 public K getKey()
    Returns the key corresponding to this entry.
 public V getValue()
    Returns the value corresponding to this entry. If the mapping
has been removed from the backing map (by the iterator's
remove operation), the results of this call are undefined.
 public int hashCode()
    Returns the hash code value for this map entry. The hash code
of a map entry e is defined to be: 
    (e.getKey()==null ? 0 : e.getKey().hashCode()) ^
(e.getValue()==null ? 0 : e.getValue().hashCode())

    
This ensures that e1.equals(e2) implies that
e1.hashCode()==e2.hashCode() for any two Entries
e1 and e2, as required by the general
contract of Object.hashCode.
 public V setValue(V value)
    Replaces the value corresponding to this entry with the specified
value (optional operation). (Writes through to the map.) The
behavior of this call is undefined if the mapping has already been
removed from the map (by the iterator's remove operation).