PropertyChangeEvent (Java Platform SE 8 ) (original) (raw)

• 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.
See Also:
Serialized Form

• • Field Summary

     * ### Fields inherited from class java.util.[EventObject](../../java/util/EventObject.html "class in java.util")  
     `[source](../../java/util/EventObject.html#source)`  

  • Constructor Summary

  Constructors

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

  • Method Summary

  All Methods Instance Methods Concrete Methods

  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 inherited from class java.util.[EventObject](../../java/util/EventObject.html "class in java.util")  
     `[getSource](../../java/util/EventObject.html#getSource--)`  
     * ### Methods inherited from class java.lang.[Object](../../java/lang/Object.html "class in java.lang")  
     `[clone](../../java/lang/Object.html#clone--), [equals](../../java/lang/Object.html#equals-java.lang.Object-), [finalize](../../java/lang/Object.html#finalize--), [getClass](../../java/lang/Object.html#getClass--), [hashCode](../../java/lang/Object.html#hashCode--), [notify](../../java/lang/Object.html#notify--), [notifyAll](../../java/lang/Object.html#notifyAll--), [wait](../../java/lang/Object.html#wait--), [wait](../../java/lang/Object.html#wait-long-), [wait](../../java/lang/Object.html#wait-long-int-)`

• • Constructor Detail

     * #### PropertyChangeEvent  
     public PropertyChangeEvent([Object](../../java/lang/Object.html "class in java.lang") source,  
                                [String](../../java/lang/String.html "class in java.lang") propertyName,  
                                [Object](../../java/lang/Object.html "class in java.lang") oldValue,  
                                [Object](../../java/lang/Object.html "class in java.lang") 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](../../java/lang/IllegalArgumentException.html "class in java.lang")` \- if `source` is `null`  

  • Method Detail

    * #### getPropertyName  
    public [String](../../java/lang/String.html "class in java.lang") 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](../../java/lang/Object.html "class in java.lang") 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](../../java/lang/Object.html "class in java.lang") 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](../../java/lang/Object.html "class in java.lang") propagationId)  
    Sets the propagationId object for the event.  
    Parameters:  
    `propagationId` \- The propagationId object for the event.  
    * #### getPropagationId  
    public [Object](../../java/lang/Object.html "class in java.lang") 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](../../java/lang/String.html "class in java.lang") toString()  
    Returns a string representation of the object.  
    Overrides:  
    `[toString](../../java/util/EventObject.html#toString--)` in class `[EventObject](../../java/util/EventObject.html "class in java.util")`  
    Returns:  
    a string representation of the object  
    Since:  
    1.7

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