org.apache.jackrabbit.oak.plugins.observation

Class EventGenerator

java.lang.Object

org.apache.jackrabbit.oak.plugins.observation.EventGenerator

public class EventGenerator
extends Object

Continuation-based content diff implementation that generates EventHandler callbacks by recursing down a content diff in a way that guarantees that only a finite number of callbacks will be made during a generate() method call, regardless of how large or complex the content diff is.

A simple usage pattern would look like this:

 EventGenerator generator = new EventGenerator(before, after, handler);
 while (!generator.isDone()) {
     generator.generate();
 }
 

Constructor Summary

Constructors

Constructor and Description
EventGenerator() Creates a new generator instance.
EventGenerator(@NotNull NodeState before, @NotNull NodeState after, @NotNull EventHandler handler) Creates a new generator instance for processing the given changes.

Method Summary

Modifier and Type	Method and Description
void	addHandler(NodeState before, NodeState after, EventHandler handler)
void	generate() Generates a finite number of EventHandler callbacks based on the content changes that have yet to be processed.
boolean	isDone() Checks whether there are no more content changes to be processed.

Methods inherited from class java.lang.Object

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

Constructor Detail

EventGenerator

public EventGenerator()

Creates a new generator instance. Changes to process need to be added through addHandler(NodeState, NodeState, EventHandler)

EventGenerator

public EventGenerator(@NotNull
                      @NotNull NodeState before,
                      @NotNull
                      @NotNull NodeState after,
                      @NotNull
                      @NotNull EventHandler handler)

Creates a new generator instance for processing the given changes.

Method Detail

addHandler

public void addHandler(NodeState before,
                       NodeState after,
                       EventHandler handler)

isDone

public boolean isDone()

Checks whether there are no more content changes to be processed.

generate

public void generate()

Generates a finite number of EventHandler callbacks based on the content changes that have yet to be processed. Further processing (even if no callbacks were made) may be postponed to a future generate() call, until the isDone() method finally return true.