com.artima.place
Class PlaceChangeEvent

java.lang.Object
  |
  +--java.util.EventObject
        |
        +--com.artima.place.PlaceChangeEvent

All Implemented Interfaces:

java.io.Serializable

public class PlaceChangeEvent

extends java.util.EventObject

An event that indicates a change in the contents of a DynamicPlace. This event will only be fired if at least one link was altered, added, or removed. A single PlaceChangeEvent may be used to report multiple alterations, additions, and/or removals. Each alteration, addition, or removal of a particular DynamicPlace is reported in one and only one PlaceChangeEvent.

See Also:

Serialized Form

Field Summary

static int	KEYS_ADDED
static int	KEYS_ALTERED
static int	KEYS_REMOVED

Fields inherited from class java.util.EventObject

source

Constructor Summary

PlaceChangeEvent(DynamicPlace source, java.lang.Object[] keysAltered, java.lang.Object[] keysAdded, java.lang.Object[] keysRemoved)
Constructs a PlaceChangeEvent object with the specified keys altered, added, and removed.

Method Summary

java.lang.Object[]	getKeysAdded() Returns an array of Object keys for those links that have been added.
java.lang.Object[]	getKeysAltered() Returns an array of Object keys for those links that have been altered.
java.lang.Object[]	getKeysRemoved() Returns an array of Object keys for those links that have been removed.
int	getType() Returns a bitwise OR of all the types of key change events reported by this PlaceChangeEvent, where the three types are PlaceChangeEvent.KEYS_ALTERED, PlaceChangeEvent.KEYS_ADDED, and PlaceChangeEvent.KEYS_REMOVED.

Methods inherited from class java.util.EventObject

getSource, toString

Methods inherited from class java.lang.Object

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

Field Detail

KEYS_ALTERED

public static final int KEYS_ALTERED

KEYS_ADDED

public static final int KEYS_ADDED

KEYS_REMOVED

public static final int KEYS_REMOVED

Constructor Detail

PlaceChangeEvent

public PlaceChangeEvent(DynamicPlace source,
                        java.lang.Object[] keysAltered,
                        java.lang.Object[] keysAdded,
                        java.lang.Object[] keysRemoved)

Constructs a PlaceChangeEvent object with the specified keys altered, added, and removed. To indicate that no values have been altered (or added, or removed), either an empty Object array or a null reference must be passed in the keysAltered (or keysAdded or keysRemoved) parameter.

Parameters:

source - the source of this PlaceChangeEvent

keysAltered - an array of keys whose LinkItem values have been altered

keysAdded - an array of keys associated with LinkItem values that have been added

keysRemoved - an array of keys associated with LinkItem values that have been removed

Throws:

NullPointerException - if passed source is null

Method Detail

getType

public int getType()

Returns a bitwise OR of all the types of key change events reported by this PlaceChangeEvent, where the three types are PlaceChangeEvent.KEYS_ALTERED, PlaceChangeEvent.KEYS_ADDED, and PlaceChangeEvent.KEYS_REMOVED.

getKeysAltered

public java.lang.Object[] getKeysAltered()

Returns an array of Object keys for those links that have been altered. A link is "altered" if a value for that key already existed in the Place, and the value was altered or replaced a new value. If no links have been altered since the previous PlaceChangeEvent was propagated (or since the DynamicPlace was sent to the client if this is the first PlaceChangeEvent propagated), this method returns an empty Object array. This method never returns null.

Returns:

the array of altered keys

getKeysAdded

public java.lang.Object[] getKeysAdded()

Returns an array of Object keys for those links that have been added. A link is "added" if the key for a newly added LinkItem value did not previously exist in the Place. If no links have been added since the previous PlaceChangeEvent was propagated (or since the DynamicPlace was sent to the client if this is the first PlaceChangeEvent propagated), this method returns an empty Object array. This method never returns null.

Returns:

the array of added keys

getKeysRemoved

public java.lang.Object[] getKeysRemoved()

Returns an array of Object keys for those links that have been removed. A link is "removed" if its key previously existed in the Place, but now does not. If no links have been removed since the previous PlaceChangeEvent was propagated (or since the DynamicPlace was sent to the client if this is the first PlaceChangeEvent propagated), this method returns an empty Object array. This method never returns null.

Returns:

the array of removed keys