Class MapExpression<K,V>

java.lang.Object

javafx.beans.binding.MapExpression<K,V>

Type Parameters:: K - the type of the key elements; V - the type of the value elements

All Implemented Interfaces:: Map<K,V>, Observable, ObservableMapValue<K,V>, ObservableObjectValue<ObservableMap<K,V>>, ObservableValue<ObservableMap<K,V>>, ObservableMap<K,V>

Direct Known Subclasses:: MapBinding, ReadOnlyMapProperty

public abstract class MapExpression<K,V> extends Object implements ObservableMapValue<K,V>

MapExpression is an ObservableMapValue plus additional convenience methods to generate bindings in a fluent style.

A concrete sub-class of MapExpression has to implement the method ObservableObjectValue.get(), which provides the actual value of this expression.

If the wrapped list of a MapExpression is null, all methods implementing the Map interface will behave as if they were applied to an immutable empty list.

Since:: JavaFX 2.1

Property Summary

Type	Property	Description
`abstract ReadOnlyBooleanProperty`	`empty`	A boolean property that is `true`, if the map is empty.
`abstract ReadOnlyIntegerProperty`	`size`	An integer property that represents the size of the map.

Nested Class Summary

Nested classes/interfaces declared in interface java.util.Map

Map.Entry<K,V>

Constructor Summary

Constructor	Description
`MapExpression()`	Creates a default `MapExpression`.

Method Summary

Modifier and Type	Method	Description
`StringBinding`	`asString()`	Creates a `StringBinding` that holds the value of the `MapExpression` turned into a `String`.
`void`	`clear()`
`boolean`	`containsKey(Object obj)`
`boolean`	`containsValue(Object obj)`
`abstract ReadOnlyBooleanProperty`	`emptyProperty()`	A boolean property that is `true`, if the map is empty.
`Set<Map.Entry<K,V>>`	`entrySet()`
`V`	`get(Object key)`
`int`	`getSize()`	The size of the map
`ObservableMap<K,V>`	`getValue()`	Returns the current value of this `ObservableValue`
`boolean`	`isEmpty()`	Gets the value of the `empty` property.
`BooleanBinding`	`isEqualTo(ObservableMap<?,?> other)`	Creates a new `BooleanBinding` that holds `true` if this map is equal to another `ObservableMap`.
`BooleanBinding`	`isNotEqualTo(ObservableMap<?,?> other)`	Creates a new `BooleanBinding` that holds `true` if this map is not equal to another `ObservableMap`.
`BooleanBinding`	`isNotNull()`	Creates a new `BooleanBinding` that holds `true` if the wrapped map is not `null`.
`BooleanBinding`	`isNull()`	Creates a new `BooleanBinding` that holds `true` if the wrapped map is `null`.
`Set<K>`	`keySet()`
`static <K, V> MapExpression<K,V>`	`mapExpression(ObservableMapValue<K,V> value)`	Returns a `MapExpression` that wraps a `ObservableMapValue`.
`V`	`put(K key, V value)`
`void`	`putAll(Map<? extends K,? extends V> elements)`
`V`	`remove(Object obj)`
`int`	`size()`
`abstract ReadOnlyIntegerProperty`	`sizeProperty()`	An integer property that represents the size of the map.
`ObjectBinding<V>`	`valueAt(ObservableValue<K> key)`	Creates a new `ObjectBinding` that contains the mapping of the specified key.
`ObjectBinding<V>`	`valueAt(K key)`	Creates a new `ObjectBinding` that contains the mapping of the specified key.
`Collection<V>`	`values()`

Methods declared in class java.lang.Object

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

Methods declared in interface java.util.Map

compute, computeIfAbsent, computeIfPresent, equals, forEach, getOrDefault, hashCode, merge, putIfAbsent, remove, replace, replace, replaceAll

Methods declared in interface javafx.beans.Observable

addListener, removeListener, subscribe

Methods declared in interface javafx.collections.ObservableMap

addListener, removeListener

Methods declared in interface javafx.beans.value.ObservableObjectValue

get

Methods declared in interface javafx.beans.value.ObservableValue

addListener, flatMap, map, orElse, removeListener, subscribe, subscribe, when

Property Details

size

public abstract ReadOnlyIntegerProperty sizeProperty

An integer property that represents the size of the map.

See Also:

getSize()
sizeProperty()

empty

public abstract ReadOnlyBooleanProperty emptyProperty

A boolean property that is true, if the map is empty.

See Also:

isEmpty()
emptyProperty()

Constructor Details

MapExpression

public MapExpression()

Creates a default MapExpression.

Method Details

getValue

public ObservableMap<K,V> getValue()

Description copied from interface: ObservableValue

Returns the current value of this ObservableValue

Specified by:: getValue in interface ObservableValue<K>
Returns:: The current value

mapExpression

public static <K, V> MapExpression<K,V> mapExpression(ObservableMapValue<K,V> value)

Returns a MapExpression that wraps a ObservableMapValue. If the ObservableMapValue is already a MapExpression, it will be returned. Otherwise a new MapBinding is created that is bound to the ObservableMapValue.

Type Parameters:: K - the type of the key elements; V - the type of the value elements
Parameters:: value - The source ObservableMapValue
Returns:: A MapExpression that wraps the ObservableMapValue if necessary
Throws:: NullPointerException - if value is null

getSize

public int getSize()

The size of the map

Returns:: the size

sizeProperty

public abstract ReadOnlyIntegerProperty sizeProperty()

An integer property that represents the size of the map.

Returns:

the property

See Also:

getSize()

emptyProperty

public abstract ReadOnlyBooleanProperty emptyProperty()

A boolean property that is true, if the map is empty.

Returns:

the ReadOnlyBooleanProperty

See Also:

isEmpty()

valueAt

public ObjectBinding<V> valueAt(K key)

Creates a new ObjectBinding that contains the mapping of the specified key.

Parameters:: key - the key of the mapping
Returns:: the ObjectBinding

valueAt

public ObjectBinding<V> valueAt(ObservableValue<K> key)

Creates a new ObjectBinding that contains the mapping of the specified key.

Parameters:: key - the key of the mapping
Returns:: the ObjectBinding
Throws:: NullPointerException - if key is null

isEqualTo

public BooleanBinding isEqualTo(ObservableMap<?,?> other)

Creates a new BooleanBinding that holds true if this map is equal to another ObservableMap.

Parameters:: other - the other ObservableMap
Returns:: the new BooleanBinding
Throws:: NullPointerException - if other is null

isNotEqualTo

public BooleanBinding isNotEqualTo(ObservableMap<?,?> other)

Creates a new BooleanBinding that holds true if this map is not equal to another ObservableMap.

Parameters:: other - the other ObservableMap
Returns:: the new BooleanBinding
Throws:: NullPointerException - if other is null

isNull

public BooleanBinding isNull()

Creates a new BooleanBinding that holds true if the wrapped map is null.

Returns:: the new BooleanBinding

isNotNull

public BooleanBinding isNotNull()

Creates a new BooleanBinding that holds true if the wrapped map is not null.

Returns:: the new BooleanBinding

asString

public StringBinding asString()

Creates a StringBinding that holds the value of the MapExpression turned into a String. If the value of this MapExpression changes, the value of the StringBinding will be updated automatically.

Returns:: the new StringBinding

size

public int size()

Specified by:: size in interface Map<K,V>

isEmpty

public boolean isEmpty()

Gets the value of the empty property.

Specified by:

isEmpty in interface Map<K,V>

Property description:

A boolean property that is true, if the map is empty.

Returns:

the value of the empty property

See Also:

emptyProperty()

containsKey

public boolean containsKey(Object obj)

Specified by:: containsKey in interface Map<K,V>

containsValue

public boolean containsValue(Object obj)

Specified by:: containsValue in interface Map<K,V>

put

public V put(K key, V value)

Specified by:: put in interface Map<K,V>

remove

public V remove(Object obj)

Specified by:: remove in interface Map<K,V>

putAll

public void putAll(Map<? extends K,? extends V> elements)

Specified by:: putAll in interface Map<K,V>

clear

public void clear()

Specified by:: clear in interface Map<K,V>

keySet

public Set<K> keySet()

Specified by:: keySet in interface Map<K,V>

values

public Collection<V> values()

Specified by:: values in interface Map<K,V>

entrySet

public Set<Map.Entry<K,V>> entrySet()

Specified by:: entrySet in interface Map<K,V>

get

public V get(Object key)

Specified by:: get in interface Map<K,V>

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Documentation extracted from JavaFX API Documentation.
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