Class PropertyChangeEvent

java.lang.Object
java.util.EventObject
java.beans.PropertyChangeEvent
All Implemented Interfaces:
Serializable
Direct Known Subclasses:
IndexedPropertyChangeEvent
public class PropertyChangeEvent extends EventObject
A "PropertyChange" event gets delivered whenever a bean changes a "bound" or "constrained" property. A PropertyChangeEvent object is sent as an argument to the PropertyChangeListener and VetoableChangeListener methods.

Normally PropertyChangeEvents are accompanied by the name and the old and new value of the changed property. If the new value is a primitive type (such as int or boolean) it must be wrapped as the corresponding java.lang.* Object type (such as Integer or Boolean).

Null values may be provided for the old and the new values if their true values are not known.

An event source may send a null object as the name to indicate that an arbitrary set of if its properties have changed. In this case the old and new values should also be null.

Since:
1.1
See Also:

  • Field Summary

    Fields declared in class EventObject

    source
    Modifier and Type
    Field
    Description
    protected Object
    source
    The object on which the Event initially occurred.

  • Constructor Summary

    Constructors
    Constructor
    Description
    PropertyChangeEvent(Object source, String propertyName, Object oldValue, Object newValue)
    Constructs a new PropertyChangeEvent.

  • Method Summary

    Modifier and Type
    Method
    Description
    Object
    getNewValue()
    Gets the new value for the property, expressed as an Object.
    Object
    getOldValue()
    Gets the old value for the property, expressed as an Object.
    Object
    getPropagationId()
    The "propagationId" field is reserved for future use.
    String
    getPropertyName()
    Gets the programmatic name of the property that was changed.
    void
    setPropagationId(Object propagationId)
    Sets the propagationId object for the event.
    String
    toString()
    Returns a string representation of the object.

    Methods declared in class EventObject

    getSource
    Modifier and Type
    Method
    Description
    Object
    getSource()
    The object on which the Event initially occurred.

    Methods declared in class Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
    Modifier and Type
    Method
    Description
    protected Object
    clone()
    Creates and returns a copy of this object.
    boolean
    equals(Object obj)
    Indicates whether some other object is "equal to" this one.
    protected void
    finalize()
    Deprecated, for removal: This API element is subject to removal in a future version.
    Finalization is deprecated and subject to removal in a future release.
    final Class<?>
    getClass()
    Returns the runtime class of this Object.
    int
    hashCode()
    Returns a hash code value for this object.
    final void
    notify()
    Wakes up a single thread that is waiting on this object's monitor.
    final void
    notifyAll()
    Wakes up all threads that are waiting on this object's monitor.
    final void
    wait()
    Causes the current thread to wait until it is awakened, typically by being notified or interrupted.
    final void
    wait(long timeoutMillis)
    Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.
    final void
    wait(long timeoutMillis, int nanos)
    Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.

  • Constructor Details

    • PropertyChangeEvent

      public PropertyChangeEvent(Object source, String propertyName, Object oldValue, Object newValue)
      Constructs a new PropertyChangeEvent.
      Parameters:
      source - the bean that fired the event
      propertyName - the programmatic name of the property that was changed
      oldValue - the old value of the property
      newValue - the new value of the property
      Throws:
      IllegalArgumentException - if source is null

  • Method Details

    • getPropertyName

      public String getPropertyName()
      Gets the programmatic name of the property that was changed.
      Returns:
      The programmatic name of the property that was changed. May be null if multiple properties have changed.

    • getNewValue

      public Object getNewValue()
      Gets the new value for the property, expressed as an Object.
      Returns:
      The new value for the property, expressed as an Object. May be null if multiple properties have changed.

    • getOldValue

      public Object getOldValue()
      Gets the old value for the property, expressed as an Object.
      Returns:
      The old value for the property, expressed as an Object. May be null if multiple properties have changed.

    • setPropagationId

      public void setPropagationId(Object propagationId)
      Sets the propagationId object for the event.
      Parameters:
      propagationId - The propagationId object for the event.

    • getPropagationId

      public Object getPropagationId()
      The "propagationId" field is reserved for future use. In Beans 1.0 the sole requirement is that if a listener catches a PropertyChangeEvent and then fires a PropertyChangeEvent of its own, then it should make sure that it propagates the propagationId field from its incoming event to its outgoing event.
      Returns:
      the propagationId object associated with a bound/constrained property update.

    • toString

      public String toString()
      Returns a string representation of the object.
      Overrides:
      toString in class EventObject
      Returns:
      a string representation of the object
      Since:
      1.7