Map.Entry

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java.util
Interface Map.Entry

All Known Implementing Classes:: AbstractMap.BasicMapEntry, IdentityHashMap.IdentityEntry, WeakHashMap.WeakBucket.WeakEntry

Enclosing interface:: Map

public static interface Map.Entry

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

Method Summary

boolean equals(java.lang.Object o)
          Compares the specified object with this entry.

java.lang.Object getKey()
          Get the key corresponding to this entry.

java.lang.Object getValue()
          Get the value corresponding to this entry.

int hashCode()
          Returns the hash code of the entry.

java.lang.Object setValue(java.lang.Object value)
          Replaces the value with the specified object (optional operation).

Method Detail

getKey

public java.lang.Object getKey()

Get the key corresponding to this entry.

getValue

public java.lang.Object getValue()

Get the value corresponding to this entry. If you already called Iterator.remove(), this is undefined.

setValue

public java.lang.Object setValue(java.lang.Object 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().

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())

equals

public boolean equals(java.lang.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()))