wt.fc
Class WTCollectionRetrySingleProcessor

java.lang.Object
  wt.fc.WTCollectionRetrySingleProcessor

Direct Known Subclasses:

StandardPersistenceManager.AbstractInsertUpdateProcessor

public abstract class WTCollectionRetrySingleProcessor

extends Object

This class implments a Template Method design pattern for executing a multi-object operation such that if it fails with an exception, a new exception can be constructed that will indicate the exact objects that failed. It does this by executing the "same" operation one object at a time and building a list of the objects that fail.

The execute(WTCollection) method executes the multi-object operation, doMultiOperation(WTCollection), in a new Transaction with a savepoint. If an exception is thrown and it is a target of this instance (determine via isTargetExceptionType(Exception), then the Transaction is rolled back to the savepoint (i.e. the datastore state prior to the multi-object operation being executed). Each object is then passed to the doSingleOperation(Persistable)and if the same type of exception occurs, then it is added to a list of failed objects. If an unexpected exception occurs or the list of failed objects is empty, then the original exception is thrown. Otherwise, a new exception is built (via buildNewException(WTCollection)) and thrown by execute(WTCollection).

Field Summary

private Object	attributeState
private static String	CLASSNAME
static boolean	DEBUG
private static DebugWriter	LOG
private Object	persistInfoState

Constructor Summary

protected	WTCollectionRetrySingleProcessor()
protected	WTCollectionRetrySingleProcessor(Object a_persistInfoState, Object a_attributeState)

Method Summary

protected abstract WTException	buildNewException(WTCollection a_failedObjects)
protected abstract void	doMultiOperation(WTCollection a_objects)
protected abstract void	doSingleOperation(Persistable a_object)
void	execute(WTCollection a_targets) This method executes a multi-object operation.
protected abstract boolean	isTargetExceptionType(Exception a_exception)
protected void	resetAttributeState(WTCollection a_objects, Object a_state)
protected Object	saveAttributeState(WTCollection a_objects)

Methods inherited from class java.lang.Object

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

Field Detail

CLASSNAME

private static final String CLASSNAME

DEBUG

public static final boolean DEBUG

LOG

private static final DebugWriter LOG

persistInfoState

private Object persistInfoState

attributeState

private Object attributeState

Constructor Detail

WTCollectionRetrySingleProcessor

protected WTCollectionRetrySingleProcessor()

WTCollectionRetrySingleProcessor

protected WTCollectionRetrySingleProcessor(Object a_persistInfoState,
                                           Object a_attributeState)

Method Detail

execute

public void execute(WTCollection a_targets)
             throws WTException

This method executes a multi-object operation.

Throws:

WTException

doMultiOperation

protected abstract void doMultiOperation(WTCollection a_objects)
                                  throws WTException

Throws:

WTException

doSingleOperation

protected abstract void doSingleOperation(Persistable a_object)
                                   throws WTException

Throws:

WTException

isTargetExceptionType

protected abstract boolean isTargetExceptionType(Exception a_exception)

buildNewException

protected abstract WTException buildNewException(WTCollection a_failedObjects)

saveAttributeState

protected Object saveAttributeState(WTCollection a_objects)

resetAttributeState

protected void resetAttributeState(WTCollection a_objects,
                                   Object a_state)