org.apache.openjpa.jdbc.meta.strats
Class AbstractDiscriminatorStrategy

java.lang.Object
  org.apache.openjpa.jdbc.meta.strats.AbstractStrategy
      org.apache.openjpa.jdbc.meta.strats.AbstractDiscriminatorStrategy

All Implemented Interfaces:

DiscriminatorStrategy, Strategy

Direct Known Subclasses:

InValueDiscriminatorStrategy, NoneDiscriminatorStrategy, SubclassJoinDiscriminatorStrategy, SuperclassDiscriminatorStrategy

public abstract class AbstractDiscriminatorStrategy
extends AbstractStrategy
implements DiscriminatorStrategy

No-op strategy for easy extension.

Author:

Abe White

Field Summary

protected Discriminator	disc The owning discriminator.
protected boolean	isFinal Whether the owning class is final.

Constructor Summary

AbstractDiscriminatorStrategy()

Method Summary

Class	getClass(JDBCStore store, ClassMapping base, Result result) Return the class for the current result row.
SQLBuffer	getClassConditions(Select sel, Joins joins, ClassMapping base, boolean subs) Return SQL to limit the classes selected as much as possible to the given base class, and optionally its subclasses.
void	loadSubclasses(JDBCStore store) By default, logs a warning that this discriminator cannot calculate its list of subclasses on its own.
boolean	select(Select sel, ClassMapping mapping) Select the data for this Discriminator.
void	setDiscriminator(Discriminator owner) Set the Discriminator that uses this strategy.

Methods inherited from class org.apache.openjpa.jdbc.meta.strats.AbstractStrategy

customDelete, customInsert, customUpdate, delete, getAlias, initialize, insert, isCustomDelete, isCustomInsert, isCustomUpdate, map, update

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.openjpa.jdbc.meta.Strategy

customDelete, customInsert, customUpdate, delete, getAlias, initialize, insert, isCustomDelete, isCustomInsert, isCustomUpdate, map, update

Field Detail

disc

protected Discriminator disc

The owning discriminator.

isFinal

protected boolean isFinal

Whether the owning class is final.

Constructor Detail

AbstractDiscriminatorStrategy

public AbstractDiscriminatorStrategy()

Method Detail

setDiscriminator

public void setDiscriminator(Discriminator owner)

Description copied from interface: DiscriminatorStrategy

Set the Discriminator that uses this strategy. This will be called before use.

Specified by:

setDiscriminator in interface DiscriminatorStrategy

select

public boolean select(Select sel,
                      ClassMapping mapping)

Description copied from interface: DiscriminatorStrategy

Select the data for this Discriminator.

Specified by:

select in interface DiscriminatorStrategy

mapping - the known base class being selected; this may not be the base class in the inheritance hierarchy

Returns:

true if anything was selected; false otherwise

loadSubclasses

public void loadSubclasses(JDBCStore store)
                    throws SQLException,
                           ClassNotFoundException

By default, logs a warning that this discriminator cannot calculate its list of subclasses on its own.

Specified by:

loadSubclasses in interface DiscriminatorStrategy

Throws:

SQLException

ClassNotFoundException

getClass

public Class getClass(JDBCStore store,
                      ClassMapping base,
                      Result result)
               throws SQLException,
                      ClassNotFoundException

Description copied from interface: DiscriminatorStrategy

Return the class for the current result row.

Specified by:

getClass in interface DiscriminatorStrategy

Throws:

SQLException

ClassNotFoundException

getClassConditions

public SQLBuffer getClassConditions(Select sel,
                                    Joins joins,
                                    ClassMapping base,
                                    boolean subs)

Description copied from interface: DiscriminatorStrategy

Return SQL to limit the classes selected as much as possible to the given base class, and optionally its subclasses. Return null if no conditions needed. The select and joins instances are supplied in order to get column aliases.

Specified by:

getClassConditions in interface DiscriminatorStrategy