Update (Apache Jackrabbit 2.23.1-beta API)

```
public interface Update
```
Update operation passed in UpdateEventChannel.

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`Object`	`getAttribute(String name)`	Return an attribute of this update operation.
`ChangeLog`	`getChanges()`	Return the local changes of this update operation.
`List<EventState>`	`getEvents()`	Return the collection of events this update operation will generate.
`long`	`getTimestamp()`	Returns the timestamp whe this update occurred.
`String`	`getUserData()`	Returns the user data associated with this update.
`void`	`setAttribute(String name, Object value)`	Set an attribute of this update operation.

- Method Detail
  - setAttribute
```
void setAttribute(String name,
                  Object value)
```
    Set an attribute of this update operation. Can be used to remember some setting for a later notification.
    
    Parameters:
    
    name - attribute name
    
    value - attribute value
  - getAttribute
```
Object getAttribute(String name)
```
    Return an attribute of this update operation.
    
    Parameters:
    
    name - attribute name
    
    Returns:
    
    attribute value or null
  - getChanges
```
ChangeLog getChanges()
```
    Return the local changes of this update operation.
    
    Returns:
    
    local changes
  - getEvents
```
List<EventState> getEvents()
```
    Return the collection of events this update operation will generate.
    
    Returns:
    
    collection of EventStates
  - getTimestamp
```
long getTimestamp()
```
    Returns the timestamp whe this update occurred.
    
    Returns:
    
    the timestamp whe this update occurred.
  - getUserData
```
String getUserData()
```
    Returns the user data associated with this update.
    
    Returns:
    
    the user data associated with this update.