RedoLog (Apache Jackrabbit 2.21.26-beta API)

```
public interface RedoLog
```
Defines a redo log for changes that have not been committed to disk. While nodes are added to and removed from the volatile index (held in memory) a redo log is maintained to keep track of the changes. In case the Jackrabbit process terminates unexpected the redo log is applied when Jackrabbit is restarted the next time.

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`void`	`append(MultiIndex.Action action)`	Appends an action to the log.
`void`	`close()`	Flushes all pending writes to the redo log and closes it.
`void`	`flush()`	Flushes all pending writes to the redo log.
`List<MultiIndex.Action>`	`getActions()`	Returns a List with all `MultiIndex.Action` instances in the redo log.
`int`	`getSize()`	Returns the number of entries in this redo log.
`boolean`	`hasEntries()`	Returns `true` if this redo log contains any entries, `false` otherwise.

- Method Detail
  - hasEntries
```
boolean hasEntries()
```
    Returns true if this redo log contains any entries, false otherwise.
    
    Returns:
    
    true if this redo log contains any entries, false otherwise.
  - getSize
```
int getSize()
```
    Returns the number of entries in this redo log.
    
    Returns:
    
    the number of entries in this redo log.
  - getActions
```
List<MultiIndex.Action> getActions()
                            throws IOException
```
    Returns a List with all MultiIndex.Action instances in the redo log.
    
    Returns:
    
    an List with all MultiIndex.Action instances in the redo log.
    
    Throws:
    
    IOException - if an error occurs while reading from the redo log.
  - append
```
void append(MultiIndex.Action action)
     throws IOException
```
    Appends an action to the log.
    
    Parameters:
    
    action - the action to append.
    
    Throws:
    
    IOException - if the node cannot be written to the redo log.
  - flush
```
void flush()
    throws IOException
```
    Flushes all pending writes to the redo log.
    
    Throws:
    
    IOException - if an error occurs while writing.
  - close
```
void close()
    throws IOException
```
    Flushes all pending writes to the redo log and closes it.
    
    Throws:
    
    IOException - if an error occurs while writing.