EmptyHook (The Adobe Experience Manager SDK 2021.8.5705.20210810T082946Z-210700)

java.lang.Object
- org.apache.jackrabbit.oak.spi.commit.EmptyHook

All Implemented Interfaces:

CommitHook
```
public class EmptyHook
extends 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 Description

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

Constructor Summary

Constructors
Constructor Description

EmptyHook()

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`@NotNull 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
```
@NotNull
public @NotNull 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