Class MapChangeListener.Change<K,V>

java.lang.Object

javafx.collections.MapChangeListener.Change<K,V>

Type Parameters:: K - key type; V - value type

Enclosing interface:: MapChangeListener<K,V>

public abstract static class MapChangeListener.Change<K,V> extends Object

An elementary change done to an ObservableMap. Change contains information about a put or remove operation. Note that put operation might remove an element if there was already a value associated with the same key. In this case wasAdded() and wasRemoved() will both return true.

Since:: JavaFX 2.0

Constructor Summary

Constructor	Description
`Change(ObservableMap<K,V> map)`	Constructs a change associated with a map.

Method Summary

Modifier and Type	Method	Description
`abstract K`	`getKey()`	A key associated with the change.
`ObservableMap<K,V>`	`getMap()`	An observable map that is associated with the change.
`abstract V`	`getValueAdded()`	Get the new value of the key.
`abstract V`	`getValueRemoved()`	Get the old value of the key.
`abstract boolean`	`wasAdded()`	If this change is a result of add operation.
`abstract boolean`	`wasRemoved()`	If this change is a result of removal operation.

Methods declared in class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

Change

public Change(ObservableMap<K,V> map)

Constructs a change associated with a map.

Parameters:: map - the source of the change

Method Details

getMap

public ObservableMap<K,V> getMap()

An observable map that is associated with the change.

Returns:: the source map

wasAdded

public abstract boolean wasAdded()

If this change is a result of add operation.

Returns:: true if a new value (or key-value) entry was added to the map

wasRemoved

public abstract boolean wasRemoved()

If this change is a result of removal operation. Note that an element might be removed even as a result of put operation.

Returns:: true if an old value (or key-value) entry was removed from the map

getKey

public abstract K getKey()

A key associated with the change. If the change is a remove change, the key no longer exist in a map. Otherwise, the key got set to a new value.

Returns:: the key that changed

getValueAdded

public abstract V getValueAdded()

Get the new value of the key. Return null if this is a removal.

Returns:: the value that is now associated with the key

getValueRemoved

public abstract V getValueRemoved()

Get the old value of the key. This is null if and only if the value was added to the key that was not previously in the map.

Returns:: the value previously associated with the key

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Documentation extracted from JavaFX API Documentation.
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