com.icl.saxon.trace
Class SaxonEventMulticaster

java.lang.Object
  com.icl.saxon.trace.SaxonEventMulticaster

All Implemented Interfaces:

TraceListener, EventListener

public class SaxonEventMulticaster
extends Object
implements TraceListener

A class which implements efficient and thread-safe multi-cast event dispatching for the TraceListener evants. Grabbed from java.awt.AWTEventMulticaster

Field Summary

protected EventListener	a
protected EventListener	b

Constructor Summary

protected

SaxonEventMulticaster(EventListener a, EventListener b) Creates an event multicaster instance which chains listener-a with listener-b.

Method Summary

static TraceListener	add(TraceListener a, TraceListener b) Adds trace-listener-a with trace-listener-b and returns the resulting multicast listener.
protected static EventListener	addInternal(EventListener a, EventListener b) Returns the resulting multicast listener from adding listener-a and listener-b together.
void	close() Called at end
void	enter(NodeInfo element, Context context) Called when an element of the stylesheet gets processed
void	enterSource(NodeHandler handler, Context context) Called when a node of the source tree gets processed
void	leave(NodeInfo element, Context context) Called after an element of the stylesheet got processed
void	leaveSource(NodeHandler handler, Context context) Called after a node of the source tree got processed
void	open() Called at start
protected EventListener	remove(EventListener oldl) Removes a listener from this multicaster and returns the resulting multicast listener.
static TraceListener	remove(TraceListener l, TraceListener oldl) Removes the old trace-listener from trace-listener-l and returns the resulting multicast listener.
protected static EventListener	removeInternal(EventListener l, EventListener oldl) Returns the resulting multicast listener after removing the old listener from listener-l.
void	toplevel(NodeInfo element) Called for all top level elements

Methods inherited from class java.lang.Object

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

Field Detail

a

protected final EventListener a

b

protected final EventListener b

Constructor Detail

SaxonEventMulticaster

protected SaxonEventMulticaster(EventListener a,
                                EventListener b)

Creates an event multicaster instance which chains listener-a with listener-b.

Parameters:

a - listener-a

b - listener-b

Method Detail

remove

protected EventListener remove(EventListener oldl)

Removes a listener from this multicaster and returns the resulting multicast listener.

Parameters:

oldl - the listener to be removed

open

public void open()

Called at start

Specified by:

open in interface TraceListener

close

public void close()

Called at end

Specified by:

close in interface TraceListener

toplevel

public void toplevel(NodeInfo element)

Called for all top level elements

Specified by:

toplevel in interface TraceListener

enterSource

public void enterSource(NodeHandler handler,
                        Context context)

Called when a node of the source tree gets processed

Specified by:

enterSource in interface TraceListener

leaveSource

public void leaveSource(NodeHandler handler,
                        Context context)

Called after a node of the source tree got processed

Specified by:

leaveSource in interface TraceListener

enter

public void enter(NodeInfo element,
                  Context context)

Called when an element of the stylesheet gets processed

Specified by:

enter in interface TraceListener

leave

public void leave(NodeInfo element,
                  Context context)

Called after an element of the stylesheet got processed

Specified by:

leave in interface TraceListener

add

public static TraceListener add(TraceListener a,
                                TraceListener b)

Adds trace-listener-a with trace-listener-b and returns the resulting multicast listener.

Parameters:

a - trace-listener-a

b - trace-listener-b

remove

public static TraceListener remove(TraceListener l,
                                   TraceListener oldl)

Removes the old trace-listener from trace-listener-l and returns the resulting multicast listener.

Parameters:

l - trace-listener-l

oldl - the trace-listener being removed

addInternal

protected static EventListener addInternal(EventListener a,
                                           EventListener b)

Returns the resulting multicast listener from adding listener-a and listener-b together. If listener-a is null, it returns listener-b; If listener-b is null, it returns listener-a If neither are null, then it creates and returns a new EventMulticaster instance which chains a with b.

Parameters:

a - event listener-a

b - event listener-b

removeInternal

protected static EventListener removeInternal(EventListener l,
                                              EventListener oldl)

Returns the resulting multicast listener after removing the old listener from listener-l. If listener-l equals the old listener OR listener-l is null, returns null. Else if listener-l is an instance of SaxonEventMulticaster, then it removes the old listener from it. Else, returns listener l.

Parameters:

l - the listener being removed from

oldl - the listener being removed