MapExpression (JavaFX 8)

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:

java.util.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 java.lang.Object
implements ObservableMapValue<K,V>
```
A MapExpression is a 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

All Methods Instance Methods Abstract Methods
Type	Property and 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 inherited from interface java.util.Map
  java.util.Map.Entry<K,V>

Constructor Summary

Constructors
Constructor and Description

MapExpression()

Constructors
Constructor and Description
`MapExpression()`

Method Summary

All Methods Static Methods Instance Methods Abstract Methods Concrete Methods
Modifier and Type	Method and Description
`StringBinding`	`asString()` Creates a `StringBinding` that holds the value of the `MapExpression` turned into a `String`.
`void`	`clear()`
`boolean`	`containsKey(java.lang.Object obj)`
`boolean`	`containsValue(java.lang.Object obj)`
`abstract ReadOnlyBooleanProperty`	`emptyProperty()` A boolean property that is `true`, if the map is empty.
`java.util.Set<java.util.Map.Entry<K,V>>`	`entrySet()`
`V`	`get(java.lang.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 property empty.
`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`.
`java.util.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(java.util.Map<? extends K,? extends V> elements)`
`V`	`remove(java.lang.Object obj)`
`int`	`size()`
`abstract ReadOnlyIntegerProperty`	`sizeProperty()` An integer property that represents the size of the map.
`ObjectBinding<V>`	`valueAt(K key)` Creates a new `ObjectBinding` that contains the mapping of the specified key.
`ObjectBinding<V>`	`valueAt(ObservableValue<K> key)` Creates a new `ObjectBinding` that contains the mapping of the specified key.
`java.util.Collection<V>`	`values()`

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface javafx.beans.value.ObservableObjectValue
get

Methods inherited from interface javafx.beans.value.ObservableValue
addListener, removeListener

Methods inherited from interface javafx.beans.Observable
addListener, removeListener

Methods inherited from interface javafx.collections.ObservableMap
addListener, removeListener

Methods inherited from interface java.util.Map
compute, computeIfAbsent, computeIfPresent, equals, forEach, getOrDefault, hashCode, merge, putIfAbsent, remove, replace, replace, replaceAll

- Property Detail
  - size
```
public abstract ReadOnlyIntegerProperty sizeProperty
```
    An integer property that represents the size of the map.
    
    See Also:
    
    getSize()
  - empty
```
public abstract ReadOnlyBooleanProperty emptyProperty
```
    A boolean property that is true, if the map is empty.
    
    See Also:
    
    isEmpty()
- Constructor Detail
  - MapExpression
```
public MapExpression()
```
- Method Detail
  - getValue
```
public ObservableMap<K,V> getValue()
```
    Description copied from interface: ObservableValue
    
    Returns the current value of this ObservableValue
    
    Specified by:
    
    getValue in interface ObservableValue<ObservableMap<K,V>>
    
    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.
    
    Parameters:
    
    value - The source ObservableMapValue
    
    Returns:
    
    A MapExpression that wraps the ObservableMapValue if necessary
    
    Throws:
    
    java.lang.NullPointerException - if value is null
  - getSize
```
public int getSize()
```
    The size of the map
  - sizeProperty
```
public abstract ReadOnlyIntegerProperty sizeProperty()
```
    An integer property that represents the size of the map.
    
    See Also:
    
    getSize()
  - emptyProperty
```
public abstract ReadOnlyBooleanProperty emptyProperty()
```
    A boolean property that is true, if the map is empty.
    
    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:
    
    java.lang.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:
    
    java.lang.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:
    
    java.lang.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 java.util.Map<K,V>
  - isEmpty
```
public boolean isEmpty()
```
    Gets the value of the property empty.
    
    Specified by:
    
    isEmpty in interface java.util.Map<K,V>
    
    Property description:
    
    A boolean property that is true, if the map is empty.
  - containsKey
```
public boolean containsKey(java.lang.Object obj)
```
    Specified by:
    
    containsKey in interface java.util.Map<K,V>
  - containsValue
```
public boolean containsValue(java.lang.Object obj)
```
    Specified by:
    
    containsValue in interface java.util.Map<K,V>
  - put
```
public V put(K key,
             V value)
```
    Specified by:
    
    put in interface java.util.Map<K,V>
  - remove
```
public V remove(java.lang.Object obj)
```
    Specified by:
    
    remove in interface java.util.Map<K,V>
  - putAll
```
public void putAll(java.util.Map<? extends K,? extends V> elements)
```
    Specified by:
    
    putAll in interface java.util.Map<K,V>
  - clear
```
public void clear()
```
    Specified by:
    
    clear in interface java.util.Map<K,V>
  - keySet
```
public java.util.Set<K> keySet()
```
    Specified by:
    
    keySet in interface java.util.Map<K,V>
  - values
```
public java.util.Collection<V> values()
```
    Specified by:
    
    values in interface java.util.Map<K,V>
  - entrySet
```
public java.util.Set<java.util.Map.Entry<K,V>> entrySet()
```
    Specified by:
    
    entrySet in interface java.util.Map<K,V>
  - get
```
public V get(java.lang.Object key)
```
    Specified by:
    
    get in interface java.util.Map<K,V>

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Class MapExpression<K,V>

Property Summary

Nested Class Summary

Nested classes/interfaces inherited from interface java.util.Map

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Methods inherited from interface javafx.beans.value.ObservableObjectValue

Methods inherited from interface javafx.beans.value.ObservableValue

Methods inherited from interface javafx.beans.Observable

Methods inherited from interface javafx.collections.ObservableMap

Methods inherited from interface java.util.Map

Property Detail

size

empty

Constructor Detail

MapExpression

Method Detail

getValue

mapExpression

getSize

sizeProperty

emptyProperty

valueAt

valueAt

isEqualTo

isNotEqualTo

isNull

isNotNull

asString

size

isEmpty

containsKey

containsValue

put

remove

putAll

clear

keySet

values

entrySet

get