Package groovy.util

Class ObservableList

java.lang.Object
groovy.util.ObservableList
All Implemented Interfaces:
Iterable, Collection, List
public class ObservableList extends Object implements List
List decorator that will trigger PropertyChangeEvents when a value changes.
An optional Closure may be specified and will work as a filter, if it returns true the property will trigger an event (if the value indeed changed), otherwise it won't. The Closure may receive 1 or 2 parameters, the single one being the value, the other one both the key and value, for example: 
 // skip all properties whose value is a closure
 def map = new ObservableList( {!(it instanceof Closure)} )

 // skip all properties whose name matches a regex
 def map = new ObservableList( { name, value -> !(name =˜ /[A-Z+]/) } )
The current implementation will trigger specialized events in the following scenarios, you need not register a different listener as those events extend from PropertyChangeEvent
  • ObservableList.ElementAddedEvent - a new element is added to the list
  • ObservableList.ElementRemovedEvent - an element is removed from the list
  • ObservableList.ElementUpdatedEvent - an element changes value (same as regular PropertyChangeEvent)
  • ObservableList.ElementClearedEvent - all elements have been removed from the list
  • ObservableList.MultiElementAddedEvent - triggered by calling list.addAll()
  • ObservableList.MultiElementRemovedEvent - triggered by calling list.removeAll()/list.retainAll()

Bound properties

  • content - read-only.
  • size - read-only.

  • Field Details

    • SIZE_PROPERTY

      public static final String SIZE_PROPERTY
      Bound property name for list size changes.
      See Also:

    • CONTENT_PROPERTY

      public static final String CONTENT_PROPERTY
      Bound property name for list content changes.
      See Also:

  • Constructor Details

    • ObservableList

      public ObservableList()
      Creates an observable list backed by an ArrayList.

    • ObservableList

      public ObservableList(List delegate)
      Creates an observable list backed by the supplied delegate.
      Parameters:
      delegate - the backing list

    • ObservableList

      public ObservableList(Closure test)
      Creates an observable list backed by an ArrayList.
      Parameters:
      test - optional event filter

    • ObservableList

      public ObservableList(List delegate, Closure test)
      Creates an observable list backed by the supplied delegate.
      Parameters:
      delegate - the backing list
      test - optional event filter

  • Method Details

    • getContent

      public List getContent()
      Returns an unmodifiable snapshot view of the backing list.
      Returns:
      the list content

    • getDelegateList

      protected List getDelegateList()
      Returns the mutable backing list.
      Returns:
      the delegate list

    • getTest

      protected Closure getTest()
      Returns the optional event filter closure.
      Returns:
      the event filter, or null

    • fireElementAddedEvent

      protected void fireElementAddedEvent(int index, Object element)
      Fires a single-element added event.

    • fireMultiElementAddedEvent

      protected void fireMultiElementAddedEvent(int index, List values)
      Fires a multi-element added event.

    • fireElementClearedEvent

      protected void fireElementClearedEvent(List values)
      Fires a cleared event containing removed values.

    • fireElementRemovedEvent

      protected void fireElementRemovedEvent(int index, Object element)
      Fires a single-element removed event.

    • fireMultiElementRemovedEvent

      protected void fireMultiElementRemovedEvent(List values)
      Fires a multi-element removed event.

    • fireElementUpdatedEvent

      protected void fireElementUpdatedEvent(int index, Object oldValue, Object newValue)
      Fires a single-element updated event.

    • fireElementEvent

      protected void fireElementEvent(ObservableList.ElementEvent event)
      Publishes an element event to registered listeners.

    • fireSizeChangedEvent

      protected void fireSizeChangedEvent(int oldValue, int newValue)
      Fires the bound size change event.

    • add

      public void add(int index, Object element)
      Specified by:
      add in interface List

    • add

      public boolean add(Object o)
      Specified by:
      add in interface Collection
      Specified by:
      add in interface List

    • addAll

      public boolean addAll(Collection c)
      Specified by:
      addAll in interface Collection
      Specified by:
      addAll in interface List

    • addAll

      public boolean addAll(int index, Collection c)
      Specified by:
      addAll in interface List

    • clear

      public void clear()
      Specified by:
      clear in interface Collection
      Specified by:
      clear in interface List

    • contains

      public boolean contains(Object o)
      Specified by:
      contains in interface Collection
      Specified by:
      contains in interface List

    • containsAll

      public boolean containsAll(Collection c)
      Specified by:
      containsAll in interface Collection
      Specified by:
      containsAll in interface List

    • equals

      public boolean equals(Object o)
      Specified by:
      equals in interface Collection
      Specified by:
      equals in interface List
      Overrides:
      equals in class Object

    • get

      public Object get(int index)
      Specified by:
      get in interface List

    • hashCode

      public int hashCode()
      Specified by:
      hashCode in interface Collection
      Specified by:
      hashCode in interface List
      Overrides:
      hashCode in class Object

    • indexOf

      public int indexOf(Object o)
      Specified by:
      indexOf in interface List

    • isEmpty

      public boolean isEmpty()
      Specified by:
      isEmpty in interface Collection
      Specified by:
      isEmpty in interface List

    • iterator

      public Iterator iterator()
      Specified by:
      iterator in interface Collection
      Specified by:
      iterator in interface Iterable
      Specified by:
      iterator in interface List

    • lastIndexOf

      public int lastIndexOf(Object o)
      Specified by:
      lastIndexOf in interface List

    • listIterator

      public ListIterator listIterator()
      Specified by:
      listIterator in interface List

    • listIterator

      public ListIterator listIterator(int index)
      Specified by:
      listIterator in interface List

    • remove

      public Object remove(int index)
      Specified by:
      remove in interface List

    • remove

      public boolean remove(Object o)
      Specified by:
      remove in interface Collection
      Specified by:
      remove in interface List

    • removeAll

      public boolean removeAll(Collection c)
      Specified by:
      removeAll in interface Collection
      Specified by:
      removeAll in interface List

    • retainAll

      public boolean retainAll(Collection c)
      Specified by:
      retainAll in interface Collection
      Specified by:
      retainAll in interface List

    • set

      public Object set(int index, Object element)
      Specified by:
      set in interface List

    • size

      public int size()
      Specified by:
      size in interface Collection
      Specified by:
      size in interface List

    • getSize

      public int getSize()
      Returns the current list size as a bound property value.
      Returns:
      the current list size

    • subList

      public List subList(int fromIndex, int toIndex)
      Specified by:
      subList in interface List

    • toArray

      public Object[] toArray()
      Specified by:
      toArray in interface Collection
      Specified by:
      toArray in interface List

    • toArray

      public Object[] toArray(Object[] a)
      Specified by:
      toArray in interface Collection
      Specified by:
      toArray in interface List

    • addPropertyChangeListener

      public void addPropertyChangeListener(PropertyChangeListener listener)
      Registers a listener for all observable list events.
      Parameters:
      listener - the listener to add

    • addPropertyChangeListener

      public void addPropertyChangeListener(String propertyName, PropertyChangeListener listener)
      Registers a listener for a named bound property.
      Parameters:
      propertyName - the property to observe
      listener - the listener to add

    • getPropertyChangeListeners

      public PropertyChangeListener[] getPropertyChangeListeners()
      Returns listeners registered for all properties.
      Returns:
      the registered listeners

    • getPropertyChangeListeners

      public PropertyChangeListener[] getPropertyChangeListeners(String propertyName)
      Returns listeners registered for a named property.
      Parameters:
      propertyName - the observed property name
      Returns:
      the registered listeners

    • removePropertyChangeListener

      public void removePropertyChangeListener(PropertyChangeListener listener)
      Removes a listener registered for all properties.
      Parameters:
      listener - the listener to remove

    • removePropertyChangeListener

      public void removePropertyChangeListener(String propertyName, PropertyChangeListener listener)
      Removes a listener registered for a named property.
      Parameters:
      propertyName - the observed property name
      listener - the listener to remove

    • hasListeners

      public boolean hasListeners(String propertyName)
      Reports whether listeners are registered for a named property.
      Parameters:
      propertyName - the property name to inspect
      Returns:
      true if listeners are registered