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package javax.management;
import java.util.List;
import java.util.Vector;
Provides an implementation of the NotificationFilter interface. The filtering is performed on the notification type attribute.
Manages a list of enabled notification types.
A method allows users to enable/disable as many notification types as required.
Then, before sending a notification to a listener registered with a filter,
the notification broadcaster compares this notification type with all notification types
enabled by the filter. The notification will be sent to the listener
only if its filter enables this notification type.
Example:
NotificationFilterSupport myFilter = new NotificationFilterSupport();
myFilter.enableType("my_example.my_type");
myBroadcaster.addListener(myListener, myFilter, null);
The listener myListener will only receive notifications the type of which equals/starts with "my_example.my_type".
See Also: Since: 1.5
/**
* Provides an implementation of the {@link javax.management.NotificationFilter} interface.
* The filtering is performed on the notification type attribute.
* <P>
* Manages a list of enabled notification types.
* A method allows users to enable/disable as many notification types as required.
* <P>
* Then, before sending a notification to a listener registered with a filter,
* the notification broadcaster compares this notification type with all notification types
* enabled by the filter. The notification will be sent to the listener
* only if its filter enables this notification type.
* <P>
* Example:
* <BLOCKQUOTE>
* <PRE>
* NotificationFilterSupport myFilter = new NotificationFilterSupport();
* myFilter.enableType("my_example.my_type");
* myBroadcaster.addListener(myListener, myFilter, null);
* </PRE>
* </BLOCKQUOTE>
* The listener <CODE>myListener</CODE> will only receive notifications the type of which equals/starts with "my_example.my_type".
*
* @see javax.management.NotificationBroadcaster#addNotificationListener
*
* @since 1.5
*/
public class NotificationFilterSupport implements NotificationFilter {
/* Serial version */
private static final long serialVersionUID = 6579080007561786969L;
@serial Vector that contains the enabled notification types. The default value is an empty vector.
/**
* @serial {@link Vector} that contains the enabled notification types.
* The default value is an empty vector.
*/
@SuppressWarnings("serial") // Not statically typed as Serializable
private List<String> enabledTypes = new Vector<String>();
Constructs a NotificationFilterSupport. /**
* Constructs a {@code NotificationFilterSupport}.
*/
public NotificationFilterSupport() {}
Invoked before sending the specified notification to the listener.
This filter compares the type of the specified notification with each enabled type.
If the notification type matches one of the enabled types,
the notification should be sent to the listener and this method returns true.
Params: - notification – The notification to be sent.
Returns: true if the notification should be sent to the listener, false otherwise.
/**
* Invoked before sending the specified notification to the listener.
* <BR>This filter compares the type of the specified notification with each enabled type.
* If the notification type matches one of the enabled types,
* the notification should be sent to the listener and this method returns <CODE>true</CODE>.
*
* @param notification The notification to be sent.
* @return <CODE>true</CODE> if the notification should be sent to the listener, <CODE>false</CODE> otherwise.
*/
public synchronized boolean isNotificationEnabled(Notification notification) {
String type = notification.getType();
if (type == null) {
return false;
}
try {
for (String prefix : enabledTypes) {
if (type.startsWith(prefix)) {
return true;
}
}
} catch (java.lang.NullPointerException e) {
// Should never occurs...
return false;
}
return false;
}
Enables all the notifications the type of which starts with the specified prefix
to be sent to the listener.
If the specified prefix is already in the list of enabled notification types,
this method has no effect.
Example:
// Enables all notifications the type of which starts with "my_example" to be sent.
myFilter.enableType("my_example");
// Enables all notifications the type of which is "my_example.my_type" to be sent.
myFilter.enableType("my_example.my_type");
Note that:
myFilter.enableType("my_example.*");
will no match any notification type.
Params: - prefix – The prefix.
Throws: - IllegalArgumentException – The prefix parameter is null.
/**
* Enables all the notifications the type of which starts with the specified prefix
* to be sent to the listener.
* <BR>If the specified prefix is already in the list of enabled notification types,
* this method has no effect.
* <P>
* Example:
* <BLOCKQUOTE>
* <PRE>
* // Enables all notifications the type of which starts with "my_example" to be sent.
* myFilter.enableType("my_example");
* // Enables all notifications the type of which is "my_example.my_type" to be sent.
* myFilter.enableType("my_example.my_type");
* </PRE>
* </BLOCKQUOTE>
*
* Note that:
* <BLOCKQUOTE><CODE>
* myFilter.enableType("my_example.*");
* </CODE></BLOCKQUOTE>
* will no match any notification type.
*
* @param prefix The prefix.
* @exception java.lang.IllegalArgumentException The prefix parameter is null.
*/
public synchronized void enableType(String prefix)
throws IllegalArgumentException {
if (prefix == null) {
throw new IllegalArgumentException("The prefix cannot be null.");
}
if (!enabledTypes.contains(prefix)) {
enabledTypes.add(prefix);
}
}
Removes the given prefix from the prefix list.
If the specified prefix is not in the list of enabled notification types,
this method has no effect.
Params: - prefix – The prefix.
/**
* Removes the given prefix from the prefix list.
* <BR>If the specified prefix is not in the list of enabled notification types,
* this method has no effect.
*
* @param prefix The prefix.
*/
public synchronized void disableType(String prefix) {
enabledTypes.remove(prefix);
}
Disables all notification types.
/**
* Disables all notification types.
*/
public synchronized void disableAllTypes() {
enabledTypes.clear();
}
Gets all the enabled notification types for this filter.
Returns: The list containing all the enabled notification types.
/**
* Gets all the enabled notification types for this filter.
*
* @return The list containing all the enabled notification types.
*/
public synchronized Vector<String> getEnabledTypes() {
return (Vector<String>)enabledTypes;
}
}