org.dellroad.stuff.pobj
Class PersistentFileTransaction

java.lang.Object
  org.dellroad.stuff.pobj.PersistentFileTransaction

public class PersistentFileTransaction
extends Object

Represents an open "transaction" on a PersistentObject's persistent file.

This class is used by PersistentObjectSchemaUpdater and would normally not be used directly.

Constructor Summary

PersistentFileTransaction(File file)
Constructor.

Method Summary

void	addUpdate(String name) Add an update to the list associated with this transaction.
void	commit() Commit this transaction.
byte[]	getData() Get the current XML data.
List<String>	getUpdates() Get the updates list associated with this transaction.
void	rollback() Cancel this transaction.
void	setData(byte[] data) Set the current XML data.
void	transform(Transformer transformer) Apply an XSLT transform to the current XML object in this transaction.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

PersistentFileTransaction

public PersistentFileTransaction(File file)
                          throws IOException,
                                 XMLStreamException

Constructor.

Parameters:

file - persistent file

Throws:

PersistentObjectException - if no updates are found

IOException

XMLStreamException

Method Detail

getData

public byte[] getData()

Get the current XML data. Does not include the XML update list.

setData

public void setData(byte[] data)

Set the current XML data. Data should not include the XML update list.

commit

public void commit()
            throws IOException,
                   XMLStreamException

Commit this transaction. This results in the persistent file being atomically overwritten (including update list).

Throws:

IOException

XMLStreamException

rollback

public void rollback()

Cancel this transaction.

getUpdates

public List<String> getUpdates()

Get the updates list associated with this transaction.

Returns:

unmodifiable list of updates

addUpdate

public void addUpdate(String name)

Add an update to the list associated with this transaction.

transform

public void transform(Transformer transformer)
               throws TransformerException

Apply an XSLT transform to the current XML object in this transaction.

Throws:

IllegalStateException - if the current root object is null

PersistentObjectException - if an error occurs

TransformerException - if the transformation fails