public static interface Map.Entry<K,V>
Map.entrySet()| Modifier and Type | Method and Description |
|---|---|
static <K extends Comparable<? super K>,V> |
comparingByKey()
Returns a comparator that compares
Map.Entry in natural order on key. |
static <K,V> Comparator<Map.Entry<K,V>> |
comparingByKey(Comparator<? super K> cmp)
Returns a comparator that compares
Map.Entry by key using the given
Comparator. |
static <K,V extends Comparable<? super V>> |
comparingByValue()
Returns a comparator that compares
Map.Entry in natural order on value. |
static <K,V> Comparator<Map.Entry<K,V>> |
comparingByValue(Comparator<? super V> cmp)
Returns a comparator that compares
Map.Entry by value using the given
Comparator. |
boolean |
equals(Object o)
Compares the specified object with this entry for equality.
|
K |
getKey()
Returns the key corresponding to this entry.
|
V |
getValue()
Returns the value corresponding to this entry.
|
int |
hashCode()
Returns the hash code value for this map entry.
|
V |
setValue(V value)
Replaces the value corresponding to this entry with the specified
value (optional operation).
|
K getKey()
IllegalStateException - implementations may, but are not
required to, throw this exception if the entry has been
removed from the backing map.V getValue()
IllegalStateException - implementations may, but are not
required to, throw this exception if the entry has been
removed from the backing map.V setValue(V value)
value - new value to be stored in this entryUnsupportedOperationException - if the put operation
is not supported by the backing mapClassCastException - if the class of the specified value
prevents it from being stored in the backing mapNullPointerException - if the backing map does not permit
null values, and the specified value is nullIllegalArgumentException - if some property of this value
prevents it from being stored in the backing mapIllegalStateException - implementations may, but are not
required to, throw this exception if the entry has been
removed from the backing map.boolean equals(Object o)
(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.equals in class Objecto - object to be compared for equality with this map entryObject.hashCode(),
HashMapint hashCode()
(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.hashCode in class ObjectObject.hashCode(),
Object.equals(Object),
equals(Object)static <K extends Comparable<? super K>,V> Comparator<Map.Entry<K,V>> comparingByKey()
Map.Entry in natural order on key.
The returned comparator is serializable and throws NullPointerException when comparing an entry with a null key.
K - the Comparable type of then map keysV - the type of the map valuesMap.Entry in natural order on key.Comparablestatic <K,V extends Comparable<? super V>> Comparator<Map.Entry<K,V>> comparingByValue()
Map.Entry in natural order on value.
The returned comparator is serializable and throws NullPointerException when comparing an entry with null values.
K - the type of the map keysV - the Comparable type of the map valuesMap.Entry in natural order on value.Comparablestatic <K,V> Comparator<Map.Entry<K,V>> comparingByKey(Comparator<? super K> cmp)
Map.Entry by key using the given
Comparator.
The returned comparator is serializable if the specified comparator is also serializable.
K - the type of the map keysV - the type of the map valuescmp - the key ComparatorMap.Entry by the key.static <K,V> Comparator<Map.Entry<K,V>> comparingByValue(Comparator<? super V> cmp)
Map.Entry by value using the given
Comparator.
The returned comparator is serializable if the specified comparator is also serializable.
K - the type of the map keysV - the type of the map valuescmp - the value ComparatorMap.Entry by the value. Submit a bug or feature
For further API reference and developer documentation, see Java SE Documentation. That documentation contains more detailed, developer-targeted descriptions, with conceptual overviews, definitions of terms, workarounds, and working code examples.
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