Package com.tangosol.util

Interface InvocableMap.Entry<K,V>

Type Parameters:

K - the type of the Map entry key

V - the type of the Map entry value

All Superinterfaces:

Map.Entry<K,V>, QueryMap.Entry<K,V>

All Known Subinterfaces:

BinaryEntry<K,V>, MapTrigger.Entry<K,V>

All Known Implementing Classes:

AbstractKeyBasedMap.EntrySet.Entry, BackingMapBinaryEntry, BinaryMap.Entry, ConverterCollections.ConverterMapEvent.ConverterMapEventBinaryEntry, InvocableMapHelper.RoutingBinaryEntry, InvocableMapHelper.RoutingMapTriggerEntry, InvocableMapHelper.SimpleEntry, ObservableSplittingBackingCache.EntrySet.Entry, OpenHashMap.EntrySet.Entry, ReadWriteBackingMap.Entry, SerializationCache.EntrySet.Entry, SimpleElement.AttributeMap.Entry, SimpleMapEntry

Enclosing interface:

InvocableMap<K,V>

public static interface InvocableMap.Entry<K,V>
extends QueryMap.Entry<K,V>

An InvocableMap.Entry contains additional information and exposes additional operations that the basic Map.Entry does not. It allows non-existent entries to be represented, thus allowing their optional creation. It allows existent entries to be removed from the Map. It supports a number of optimizations that can ultimately be mapped through to indexes and other data structures of the underlying Map.

Method Summary

Modifier and Type	Method	Description
default BinaryEntry<K,V>	asBinaryEntry()	Return this entry as a BinaryEntry.
K	getKey()	Return the key corresponding to this entry.
V	getValue()	Return the value corresponding to this entry.
default V	getValue(Supplier<V> defaultValueSupplier)	Return the value corresponding to this entry, or the default value returned by the defaultValueSupplier, if the entry value is null.
default V	getValue(V defaultValue)	Return the value corresponding to this entry, or the specified defaultValue, if the entry value is null.
boolean	isPresent()	Determine if this Entry exists in the Map.
boolean	isSynthetic()	Determine if this Entry has been synthetically mutated.
void	remove(boolean fSynthetic)	Remove this Entry from the Map if it is present in the Map.
V	setValue(V value)	Store the value corresponding to this entry.
void	setValue(V value, boolean fSynthetic)	Store the value corresponding to this entry.
<T> void	update(ValueUpdater<V,T> updater, T value)	Update the Entry's value.

Methods inherited from interface java.util.Map.Entry

equals, hashCode

Methods inherited from interface com.tangosol.util.QueryMap.Entry

extract, extractFromKey, extractFromValue

Method Details

getKey

K getKey()

Return the key corresponding to this entry. The resultant key does not necessarily exist within the containing Map, which is to say that InvocableMap.this.containsKey(getKey()) could return false. To test for the presence of this key within the Map, use isPresent(), and to create the entry for the key, use setValue(V).

Specified by:

getKey in interface Map.Entry<K,V>

Returns:

the key corresponding to this entry; may be null if the underlying Map supports null keys

getValue

V getValue()

Return the value corresponding to this entry. If the entry does not exist, then the value will be null. To differentiate between a null value and a non-existent entry, use isPresent().

Note: any modifications to the value retrieved using this method are not guaranteed to persist unless followed by a setValue(V) or update(com.tangosol.util.ValueUpdater<V, T>, T) call.

Specified by:

getValue in interface Map.Entry<K,V>

Returns:

the value corresponding to this entry; may be null if the value is null or if the Entry does not exist in the Map

setValue

V setValue(V value)

Store the value corresponding to this entry. If the entry does not exist, then the entry will be created by invoking this method, even with a null value (assuming the Map supports null values).

Specified by:

setValue in interface Map.Entry<K,V>

Parameters:

value - the new value for this Entry

Returns:

the previous value of this Entry, or null if the Entry did not exist

getValue

default V getValue(V defaultValue)

Return the value corresponding to this entry, or the specified defaultValue, if the entry value is null. To differentiate between a null value and a non-existent entry, use isPresent().

Note: any modifications to the value retrieved using this method are not guaranteed to persist unless followed by a setValue(V) or update(com.tangosol.util.ValueUpdater<V, T>, T) call.

Parameters:

defaultValue - the default value to return if the entry value is null

Returns:

the value corresponding to this entry, or the specified defaultValue, if the entry value is null

getValue

default V getValue(Supplier<V> defaultValueSupplier)

Return the value corresponding to this entry, or the default value returned by the defaultValueSupplier, if the entry value is null. To differentiate between a null value and a non-existent entry, use isPresent().

Note: any modifications to the value retrieved using this method are not guaranteed to persist unless followed by a setValue(V) or update(com.tangosol.util.ValueUpdater<V, T>, T) call.

Parameters:

defaultValueSupplier - the default value supplier to use to create the default value if the entry value is null

Returns:

the value corresponding to this entry, or the value created by the specified defaultValueSupplier, if the entry value is null

Since:

21.12

setValue

void setValue(V value,
 boolean fSynthetic)

Store the value corresponding to this entry. If the entry does not exist, then the entry will be created by invoking this method, even with a null value (assuming the Map supports null values).

Unlike the other form of setValue, this form does not return the previous value, and as a result may be significantly less expensive (in terms of cost of execution) for certain Map implementations.

Parameters:

value - the new value for this Entry

fSynthetic - pass true only if the insertion into or modification of the Map should be treated as a synthetic event

update

<T> void update(ValueUpdater<V,T> updater,
 T value)

Update the Entry's value. Calling this method is semantically equivalent to:

   V target = entry.getValue();
   updater.update(target, value);
   entry.setValue(target, false);
 

The benefit of using this method is that it may allow the Entry implementation to significantly optimize the operation, such as for purposes of delta updates and backup maintenance.

Type Parameters:

T - the class of the value

Parameters:

updater - a ValueUpdater used to modify the Entry's value

value - the new value for this Entry

isPresent

boolean isPresent()

Determine if this Entry exists in the Map. If the Entry is not present, it can be created by calling setValue(Object) or setValue(Object, boolean). If the Entry is present, it can be destroyed by calling remove(boolean).

Returns:

true iff this Entry is existent in the containing Map

isSynthetic

boolean isSynthetic()

Determine if this Entry has been synthetically mutated. This method returns false if either a non-synthetic update was made or the entry has not been modified.

Returns:

true if the Entry has been synthetically mutated

remove

void remove(boolean fSynthetic)

Remove this Entry from the Map if it is present in the Map.

This method supports both the operation corresponding to Map.remove(java.lang.Object) as well as synthetic operations such as eviction. If the containing Map does not differentiate between the two, then this method will always be identical to InvocableMap.this.remove(getKey()).

Parameters:

fSynthetic - pass true only if the removal from the Map should be treated as a synthetic event

asBinaryEntry

default BinaryEntry<K,V> asBinaryEntry()

Return this entry as a BinaryEntry.

This is a convenience method that allows you to avoid casting an Entry into a BinaryEntry within an InvocableMap.EntryProcessor implementation. It will *not* attempt to coerce this instance into a BinaryEntry.

Returns:

this entry as a BinaryEntry

Throws:

ClassCastException - if this entry is not an instance of a BinaryEntry

Since:

20.12