Package org.jitsi.service.fileaccess

Interface FailSafeTransaction

All Known Implementing Classes:

FailSafeTransactionImpl

public interface FailSafeTransaction

A failsafe transaction interface. By failsafe we mean here that the file concerned always stays in a coherent state.

Author:

Benoit Pradelle

Method Summary

Modifier and Type	Method	Description
void	beginTransaction()	Begins a new transaction.
void	commit()	Closes the transaction and commit the changes.
void	restoreFile()	Ensure that the file accessed is in a coherent state.
void	rollback()	Closes the transation and cancel the changes.

Method Detail

restoreFile

void restoreFile()
          throws IllegalStateException,
                 IOException

Ensure that the file accessed is in a coherent state. This function is useful to do a failsafe read without starting a transaction.

Throws:

IllegalStateException - if the file doesn't exists anymore

IOException - if an IOException occurs during the file restoration

beginTransaction

void beginTransaction()
               throws IllegalStateException,
                      IOException

Begins a new transaction. If a transaction is already active, commits the changes and begin a new transaction. A transaction can be closed by a commit or rollback operation. When the transaction begins, the file is restored to a coherent state if needed.

Throws:

IllegalStateException - if the file doesn't exists anymore

IOException - if an IOException occurs during the transaction creation

commit

void commit()
     throws IllegalStateException,
            IOException

Closes the transaction and commit the changes. Everything written in the file during the transaction is saved.

Throws:

IllegalStateException - if the file doesn't exists anymore

IOException - if an IOException occurs during the operation

rollback

void rollback()
       throws IllegalStateException,
              IOException

Closes the transation and cancel the changes. Everything written in the file during the transaction is NOT saved.

Throws:

IllegalStateException - if the file doesn't exists anymore

IOException - if an IOException occurs during the operation