Journal (Oracle® Coherence Java API Reference)

All Superinterfaces:

AutoCloseable, Disposable

All Known Implementing Classes:

AbstractJournalRM.JournalImpl, BackupJournalRM.JournalImpl, RamJournalRM.JournalImpl
```
public interface Journal
extends Disposable
```
The Journal interface represents data that is written as part of a stream of updates, with the ability to identify writes (and later read them) using a ticket system. The Journal does not support erasure, but does allow the Journal to discard data that has been written previously as long as it has been "released" via this interface.

Since:

Coherence 3.7

Author:

cp 2010-06-10

Nested Class Summary

Nested Classes
Modifier and Type	Interface	Description
`static interface`	`Journal.JournalConsumer`	An interface that represents the actions that a Journal may request of an object that uses the Journal.

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`Binary`	`read(long lTicket)`	Using a ticket returned from a previous call to `write(com.tangosol.util.Binary)`, read the Binary value that was written to the Journal.
`int`	`release(long lTicket)`	Notify the Journal that the value corresponding to the specified ticket is no longer needed.
`long`	`write(Binary bin)`	Write a Binary value to the Journal and return a ticket for it.

Methods inherited from interface com.oracle.coherence.common.base.Disposable
close, dispose

- Method Detail
  - write
```
long write(Binary bin)
```
    Write a Binary value to the Journal and return a ticket for it.
    
    Parameters:
    
    bin - the Binary to write to the Journal
    
    Returns:
    
    the ticket that can later be used to access the Binary
  - read
```
Binary read(long lTicket)
```
    Using a ticket returned from a previous call to write(com.tangosol.util.Binary), read the Binary value that was written to the Journal.
    
    Parameters:
    
    lTicket - a ticket returned from a previous call to write(com.tangosol.util.Binary)
    
    Returns:
    
    the Binary value that was previously written
    
    Throws:
    
    IllegalStateException - may be thrown if the passed ticket had already been released
  - release
```
int release(long lTicket)
```
    Notify the Journal that the value corresponding to the specified ticket is no longer needed.
    
    Parameters:
    
    lTicket - a ticket returned from a previous call to write(com.tangosol.util.Binary)
    
    Returns:
    
    the number of bytes released
    
    Throws:
    
    IllegalStateException - may be thrown if the passed ticket had already been released