org.apache.jackrabbit.oak.spi.commit

Class EmptyHook

java.lang.Object

org.apache.jackrabbit.oak.spi.commit.EmptyHook

All Implemented Interfaces:

CommitHook

public class EmptyHook
extends java.lang.Object
implements CommitHook

Basic commit hook implementation that by default doesn't do anything. This class has a dual purpose:

1. The static INSTANCE instance can be used as a "null object" in cases where another commit hook has not been configured, thus avoiding the need for extra code for such cases.
2. Other commit hook implementations can extend this class and gain improved forwards-compatibility to possible changes in the CommitHook interface. For example if it is later decided that new arguments are needed in the hook methods, this class is guaranteed to implement any new method signatures in a way that falls gracefully back to any earlier behavior.

Field Summary

Fields

Modifier and Type	Field and Description
static CommitHook	INSTANCE Static instance of this class, useful as a "null object".

Constructor Summary

Constructors

Constructor and Description
EmptyHook()

Method Summary

Modifier and Type	Method and Description
NodeState	processCommit(NodeState before, NodeState after, CommitInfo info) Validates and/or modifies the given content change before it gets persisted.

Methods inherited from class java.lang.Object

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

Field Detail

INSTANCE

public static final CommitHook INSTANCE

Static instance of this class, useful as a "null object".

Constructor Detail

EmptyHook

public EmptyHook()

Method Detail

processCommit

public NodeState processCommit(NodeState before,
                               NodeState after,
                               CommitInfo info)
                        throws CommitFailedException

Description copied from interface: CommitHook

Validates and/or modifies the given content change before it gets persisted.

Specified by:

processCommit in interface CommitHook

Parameters:

before - content tree before the commit

after - content tree prepared for the commit

info - metadata associated with this commit

Returns:

content tree to be committed

Throws:

CommitFailedException - if the commit should be rejected