org.onosproject.store.service

Interface TransactionalMap<K,V>

Type Parameters:

K - type of key.

V - type of value.

public interface TransactionalMap<K,V>

Transactional Map data structure.

A TransactionalMap is created by invoking getTransactionalMap method. All operations performed on this map within a transaction boundary are invisible externally until the point when the transaction commits. A commit usually succeeds in the absence of conflicts.

Method Summary

Modifier and Type	Method and Description
boolean	containsKey(K key) Returns true if this map contains a mapping for the specified key.
V	get(K key) Returns the value to which the specified key is mapped, or null if this map contains no mapping for the key.
V	put(K key, V value) Associates the specified value with the specified key in this map (optional operation).
V	putIfAbsent(K key, V value) If the specified key is not already associated with a value associates it with the given value and returns null, else returns the current value.
V	remove(K key) Removes the mapping for a key from this map if it is present (optional operation).
boolean	remove(K key, V value) Removes the entry for the specified key only if it is currently mapped to the specified value.
boolean	replace(K key, V oldValue, V newValue) Replaces the entry for the specified key only if currently mapped to the specified value.

Method Detail

get

V get(K key)

Returns the value to which the specified key is mapped, or null if this map contains no mapping for the key.

Parameters:

key - the key whose associated value is to be returned

Returns:

the value to which the specified key is mapped, or null if this map contains no mapping for the key

containsKey

boolean containsKey(K key)

Returns true if this map contains a mapping for the specified key.

Parameters:

key - key whose presence in this map to be tested

Returns:

true if this map contains a mapping for the specified key

put

V put(K key,
      V value)

Associates the specified value with the specified key in this map (optional operation). If the map previously contained a mapping for the key, the old value is replaced by the specified value.

Parameters:

key - key with which the specified value is to be associated

value - value to be associated with the specified key

Returns:

the previous value associated with key, or null if there was no mapping for key.

remove

V remove(K key)

Removes the mapping for a key from this map if it is present (optional operation).

Parameters:

key - key whose value is to be removed from the map

Returns:

the value to which this map previously associated the key, or null if the map contained no mapping for the key.

putIfAbsent

V putIfAbsent(K key,
              V value)

If the specified key is not already associated with a value associates it with the given value and returns null, else returns the current value.

Parameters:

key - key with which the specified value is to be associated

value - value to be associated with the specified key

Returns:

the previous value associated with the specified key or null if key does not already mapped to a value.

remove

boolean remove(K key,
               V value)

Removes the entry for the specified key only if it is currently mapped to the specified value.

Parameters:

key - key with which the specified value is associated

value - value expected to be associated with the specified key

Returns:

true if the value was removed

replace

boolean replace(K key,
                V oldValue,
                V newValue)

Replaces the entry for the specified key only if currently mapped to the specified value.

Parameters:

key - key with which the specified value is associated

oldValue - value expected to be associated with the specified key

newValue - value to be associated with the specified key

Returns:

true if the value was replaced