oracle.javatools.db.refactoring

Class CascadeWorker<T extends DBObject>

java.lang.Object

oracle.javatools.db.refactoring.CascadeWorker<T>

Direct Known Subclasses:

DBObjectValidator

public abstract class CascadeWorker<T extends DBObject>
extends java.lang.Object

Class responsible for doing the actual cascade of an object update or removal.

Since:

12

Constructor Summary

Constructors

Constructor and Description
CascadeWorker(DBObjectProvider pro)

Method Summary

Modifier and Type	Method and Description
protected CascadeAction	cascadeDelete(DBObjectID removed, DBObject referer, T obj) Cascade deletes the given removed object.
CascadeAction	cascadeDelete(DBObject removed, T obj) Cascade deletes the given removed object.
protected CascadeAction	cascadePropertyChange(Difference objDiff, java.lang.String propName, java.lang.Object oldValue, java.lang.Object newValue, T obj) Process the given difference from a dependent object that is being updated.
CascadeAction	cascadeUpdate(Difference objDiff, T obj) Cascades the given object difference to an object this CascadeWorker is responsible for.
java.util.Set<java.lang.String>	getCascadeProperties() Gets the property names that (if changed on any object) could require cascade work to be done by this processor.
protected java.util.logging.Logger	getLogger()
protected DBObjectProvider	getProvider()
protected CascadeAction	removeReference(DBObjectID removed, DBObject referer, PropertyInfo info) This method is called when a reference is found to a deleted object.

Methods inherited from class java.lang.Object

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

Constructor Detail

CascadeWorker

public CascadeWorker(DBObjectProvider pro)

Method Detail

getProvider

protected final DBObjectProvider getProvider()

getLogger

protected final java.util.logging.Logger getLogger()

cascadeDelete

public CascadeAction cascadeDelete(DBObject removed,
                                   T obj)
                            throws DBException

Cascade deletes the given removed object. Possible rreturn values are:

• NONE no action was required
• UPDATE obj has been updated appropriate
• DELETE obj should be deleted

Parameters:

removed - the object that we are cascading the delete of

obj - the object to cascade to

Returns:

the appropriate cascade action

Throws:

DBException - if the delete should be completely aborted. As this aborts the entire operation it should only be used for terminal errors. This should not throw a CascadeRequiredException, that is handled by the framework if an update is required.

cascadeDelete

protected final CascadeAction cascadeDelete(DBObjectID removed,
                                            DBObject referer,
                                            T obj)
                                     throws DBException

Cascade deletes the given removed object. Possible rreturn values are:

• NONE no action was required
• UPDATE obj has been updated appropriate
• DELETE obj should be deleted

Parameters:

removed - the object that we are cascading the delete of

referer - the object to cascade to

obj - the top level object that owns the referer (could be the referer)

Returns:

the appropriate cascade action

Throws:

DBException - if the delete should be completely aborted. As this aborts the entire operation it should only be used for terminal errors. This should not throw a CascadeRequiredException, that is handled by the framework if an update is required.

removeReference

protected CascadeAction removeReference(DBObjectID removed,
                                        DBObject referer,
                                        PropertyInfo info)
                                 throws DBException

This method is called when a reference is found to a deleted object. The reference can either be deleted from the object, or the object itself deleted.

Note: this method will only be called if a property is found on this object (not its children) to the deleted object.

Parameters:

removed - the id of the deleted object

referer - the object that has a reference to the deleted object

info - the PropertyInfo for the property that is the reference

Returns:

the action that should be taken. If the property was changed (by setting the reference to null or removing the reference from a list) then UPDATE should be returned. If the referer should be removed from its parent then DELETE should be returned (the remove does not need to be performed, the caller will do that).

Throws:

DBException - if the update should be completely aborted. As this aborts the entire operation it should only be used for terminal errors. This should not throw a CascadeRequiredException, that is handled by the framework if an update is required.

cascadeUpdate

public CascadeAction cascadeUpdate(Difference objDiff,
                                   T obj)
                            throws DBException

Cascades the given object difference to an object this CascadeWorker is responsible for.

Parameters:

objDiff - the changes to cascade

obj - a single object that this worker is responsible for cascading to.

Returns:

a CascadeAction to identify whether any changes were necessary.

Throws:

DBException - if the update should be completely aborted. As this aborts the entire operation it should only be used for terminal errors. This should not throw a CascadeRequiredException, that is handled by the framework if an update is required.

cascadePropertyChange

protected CascadeAction cascadePropertyChange(Difference objDiff,
                                              java.lang.String propName,
                                              java.lang.Object oldValue,
                                              java.lang.Object newValue,
                                              T obj)
                                       throws DBException

Process the given difference from a dependent object that is being updated. This does not need to recurse into the given difference if it is a DBObject, that wil be done by the framework.

Parameters:

objDiff - the full difference for the updated object

propName - the name of the changed property we are cascading

oldValue - the old property value

newValue - the new property value

obj - the object to cascade the change to

Returns:

a CascadeAction appropriate to any change made or required. If UPDATE is returned any appropriate change should have been made to obj.

Throws:

DBException - if the update should be completely aborted. As this aborts the entire operation it should only be used for terminal errors. This should not throw a CascadeRequiredException, that is handled by the framework if an update is required.

getCascadeProperties

public java.util.Set<java.lang.String> getCascadeProperties()

Gets the property names that (if changed on any object) could require cascade work to be done by this processor. If no registered CascadeWorker returns a property in its Set, then a change to that property on any object will not result in a cascade check.