org.apache.openjpa.jdbc.meta.strats

Class AbstractFieldStrategy

java.lang.Object

org.apache.openjpa.jdbc.meta.strats.AbstractStrategy

org.apache.openjpa.jdbc.meta.strats.AbstractFieldStrategy

All Implemented Interfaces:

Serializable, FieldStrategy, Strategy

Direct Known Subclasses:

ContainerFieldStrategy, EmbedFieldStrategy, HandlerFieldStrategy, LobFieldStrategy, NoneFieldStrategy, PrimitiveFieldStrategy, RelationFieldStrategy, StringFieldStrategy

public abstract class AbstractFieldStrategy
extends AbstractStrategy
implements FieldStrategy

No-op strategy for easy extension.

Author:

Abe White

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
protected FieldMapping	field The owning field mapping.

Constructor Summary

Constructors

Constructor and Description
AbstractFieldStrategy()

Method Summary

Modifier and Type	Method and Description
void	appendIndex(SQLBuffer sql, Select sel, Joins joins) Append the ordered column alias to the given statement.
void	appendIsEmpty(SQLBuffer sql, Select sel, Joins joins) Append a where clause to the given statement checking if this value is empty.
void	appendIsNotEmpty(SQLBuffer sql, Select sel, Joins joins) Append a where clause to the given statement checking if this value is not empty.
void	appendIsNotNull(SQLBuffer sql, Select sel, Joins joins) Append a where clause to the given statement checking if this value is not null.
void	appendIsNull(SQLBuffer sql, Select sel, Joins joins) Append a where clause to the given statement checking if this value is null.
void	appendSize(SQLBuffer sql, Select sel, Joins joins) Append a where clause to the given statement checking the size of the value.
void	appendType(SQLBuffer sql, Select sel, Joins joins) Append the entity discriminator value to the given statement.
protected void	assertNotMappedBy() Throws an informative exception if the field declares a mapped-by value.
boolean	isEagerSelectToMany() Whether the eager joins or selects used by this field are to-many.
boolean	isVersionable() Return true if this field can be used as part of a state image for optimistic locking.
Joins	join(Joins joins, boolean forceOuter) Join this value to the class table.
Joins	joinKey(Joins joins, boolean forceOuter) Join the key value to the class table.
Joins	joinKeyRelation(Joins joins, boolean forceOuter, boolean traverse) Join this value's table to the table for the related first class object key type, if any.
Joins	joinRelation(Joins joins, boolean forceOuter, boolean traverse) Join this value's table to the table for the related first class object type, if any.
void	load(OpenJPAStateManager sm, JDBCStore store, JDBCFetchConfiguration fetch) Load secondary data using a connection from the store manager.
void	load(OpenJPAStateManager sm, JDBCStore store, JDBCFetchConfiguration fetch, Result res) Load virtual row data; the given result is not guaranteed to contain data for this field, so the field mapping should make sure the result contains its needed column data before loading.
void	loadEagerJoin(OpenJPAStateManager sm, JDBCStore store, JDBCFetchConfiguration fetch, Result res) Load the joined eager result.
Object	loadEagerParallel(OpenJPAStateManager sm, JDBCStore store, JDBCFetchConfiguration fetch, Object res) Load the batched eager result.
Object	loadKeyProjection(JDBCStore store, JDBCFetchConfiguration fetch, Result res, Joins joins) Load this field's key value using the given result.
Object	loadProjection(JDBCStore store, JDBCFetchConfiguration fetch, Result res, Joins joins) Load this field value using the given result.
int	select(Select sel, OpenJPAStateManager sm, JDBCStore store, JDBCFetchConfiguration fetch, int eagerMode) Select the virtual row columns of this mapping.
void	selectEagerJoin(Select sel, OpenJPAStateManager sm, JDBCStore store, JDBCFetchConfiguration fetch, int eagerMode) Fill in joined select to related objects.
void	selectEagerParallel(SelectExecutor sel, OpenJPAStateManager sm, JDBCStore store, JDBCFetchConfiguration fetch, int eagerMode) Fill in parallel eager select for related objects.
void	setFieldMapping(FieldMapping owner) Set the class mapping using this strategy.
int	supportsSelect(Select sel, int type, OpenJPAStateManager sm, JDBCStore store, JDBCFetchConfiguration fetch) Return whether this mapping can perform the given select type.
Object	toDataStoreValue(Object val, JDBCStore store) Translate the given external field value to its datastore equivalent.
Object	toKeyDataStoreValue(Object val, JDBCStore store) Translate the given key value to its datastore equivalent.
void	where(OpenJPAStateManager sm, JDBCStore store, RowManager rm, Object prevValue) Add a WHERE condition to the row for this field such that the field's current DB value must equal the given previous value.

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

field

protected FieldMapping field

The owning field mapping.

Constructor Detail

AbstractFieldStrategy

public AbstractFieldStrategy()

Method Detail

assertNotMappedBy

protected void assertNotMappedBy()

Throws an informative exception if the field declares a mapped-by value.

setFieldMapping

public void setFieldMapping(FieldMapping owner)

Description copied from interface: FieldStrategy

Set the class mapping using this strategy. This will be called before use.

Specified by:

setFieldMapping in interface FieldStrategy

supportsSelect

public int supportsSelect(Select sel,
                          int type,
                          OpenJPAStateManager sm,
                          JDBCStore store,
                          JDBCFetchConfiguration fetch)

Description copied from interface: FieldStrategy

Return whether this mapping can perform the given select type. Return 0 if the given type is not supported. If the given type is an eager parallel type, return the number of UNIONed selects necessary to fetch the data. Otherwise, return any positive number if the type is supported. The given state manager may be null if selecting multiple instances.

Specified by:

supportsSelect in interface FieldStrategy

See Also:

Select

selectEagerJoin

public void selectEagerJoin(Select sel,
                            OpenJPAStateManager sm,
                            JDBCStore store,
                            JDBCFetchConfiguration fetch,
                            int eagerMode)

Description copied from interface: FieldStrategy

Fill in joined select to related objects.

Specified by:

selectEagerJoin in interface FieldStrategy

See Also:

FieldStrategy.select(org.apache.openjpa.jdbc.sql.Select, org.apache.openjpa.kernel.OpenJPAStateManager, org.apache.openjpa.jdbc.kernel.JDBCStore, org.apache.openjpa.jdbc.kernel.JDBCFetchConfiguration, int)

selectEagerParallel

public void selectEagerParallel(SelectExecutor sel,
                                OpenJPAStateManager sm,
                                JDBCStore store,
                                JDBCFetchConfiguration fetch,
                                int eagerMode)

Description copied from interface: FieldStrategy

Fill in parallel eager select for related objects.

Specified by:

selectEagerParallel in interface FieldStrategy

See Also:

FieldStrategy.select(org.apache.openjpa.jdbc.sql.Select, org.apache.openjpa.kernel.OpenJPAStateManager, org.apache.openjpa.jdbc.kernel.JDBCStore, org.apache.openjpa.jdbc.kernel.JDBCFetchConfiguration, int)

isEagerSelectToMany

public boolean isEagerSelectToMany()

Description copied from interface: FieldStrategy

Whether the eager joins or selects used by this field are to-many.

Specified by:

isEagerSelectToMany in interface FieldStrategy

select

public int select(Select sel,
                  OpenJPAStateManager sm,
                  JDBCStore store,
                  JDBCFetchConfiguration fetch,
                  int eagerMode)

Description copied from interface: FieldStrategy

Select the virtual row columns of this mapping.

Specified by:

select in interface FieldStrategy

Parameters:

sel - the select to add to

sm - the instance being loaded, or null if not initialized yet or selecting for multiple instances

store - the current store manager

fetch - fetch configuration

eagerMode - the eager fetch mode to use; this may be more restrictive than the mode of the fetch configuration

Returns:

> 0 if this mapping requires the selected data (if any), 0 if it selected data but does not require it, or < 0 if no data was selected

loadEagerParallel

public Object loadEagerParallel(OpenJPAStateManager sm,
                                JDBCStore store,
                                JDBCFetchConfiguration fetch,
                                Object res)
                         throws SQLException

Description copied from interface: FieldStrategy

Load the batched eager result.

Specified by:

loadEagerParallel in interface FieldStrategy

res - originally the Result to load from, but this method may return a processed result form that will be passed to subsequent calls

Throws:

SQLException

loadEagerJoin

public void loadEagerJoin(OpenJPAStateManager sm,
                          JDBCStore store,
                          JDBCFetchConfiguration fetch,
                          Result res)
                   throws SQLException

Description copied from interface: FieldStrategy

Load the joined eager result.

Specified by:

loadEagerJoin in interface FieldStrategy

Throws:

SQLException

load

public void load(OpenJPAStateManager sm,
                 JDBCStore store,
                 JDBCFetchConfiguration fetch,
                 Result res)
          throws SQLException

Description copied from interface: FieldStrategy

Load virtual row data; the given result is not guaranteed to contain data for this field, so the field mapping should make sure the result contains its needed column data before loading.

Specified by:

load in interface FieldStrategy

Throws:

SQLException

load

public void load(OpenJPAStateManager sm,
                 JDBCStore store,
                 JDBCFetchConfiguration fetch)
          throws SQLException

Description copied from interface: FieldStrategy

Load secondary data using a connection from the store manager.

Specified by:

load in interface FieldStrategy

Throws:

SQLException

toDataStoreValue

public Object toDataStoreValue(Object val,
                               JDBCStore store)

Description copied from interface: FieldStrategy

Translate the given external field value to its datastore equivalent. If the mapping occupies multiple columns in the datastore, return an object array, else return a single object. Simply returns the given object by default.

Specified by:

toDataStoreValue in interface FieldStrategy

toKeyDataStoreValue

public Object toKeyDataStoreValue(Object val,
                                  JDBCStore store)

Description copied from interface: FieldStrategy

Translate the given key value to its datastore equivalent. If the mapping occupies multiple columns in the datastore, return an object array, else return a single object. Simply returns the given object by default.

Specified by:

toKeyDataStoreValue in interface FieldStrategy

appendIsEmpty

public void appendIsEmpty(SQLBuffer sql,
                          Select sel,
                          Joins joins)

Description copied from interface: FieldStrategy

Append a where clause to the given statement checking if this value is empty. Appends impossible-to-satisfy SQL by default.

Specified by:

appendIsEmpty in interface FieldStrategy

appendIsNotEmpty

public void appendIsNotEmpty(SQLBuffer sql,
                             Select sel,
                             Joins joins)

Description copied from interface: FieldStrategy

Append a where clause to the given statement checking if this value is not empty. Appends always-satisfied SQL by default.

Specified by:

appendIsNotEmpty in interface FieldStrategy

appendIsNull

public void appendIsNull(SQLBuffer sql,
                         Select sel,
                         Joins joins)

Description copied from interface: FieldStrategy

Append a where clause to the given statement checking if this value is null.

Specified by:

appendIsNull in interface FieldStrategy

appendIsNotNull

public void appendIsNotNull(SQLBuffer sql,
                            Select sel,
                            Joins joins)

Description copied from interface: FieldStrategy

Append a where clause to the given statement checking if this value is not null.

Specified by:

appendIsNotNull in interface FieldStrategy

appendSize

public void appendSize(SQLBuffer sql,
                       Select sel,
                       Joins joins)

Description copied from interface: FieldStrategy

Append a where clause to the given statement checking the size of the value.

Specified by:

appendSize in interface FieldStrategy

appendIndex

public void appendIndex(SQLBuffer sql,
                        Select sel,
                        Joins joins)

Description copied from interface: FieldStrategy

Append the ordered column alias to the given statement.

Specified by:

appendIndex in interface FieldStrategy

appendType

public void appendType(SQLBuffer sql,
                       Select sel,
                       Joins joins)

Description copied from interface: FieldStrategy

Append the entity discriminator value to the given statement.

Specified by:

appendType in interface FieldStrategy

join

public Joins join(Joins joins,
                  boolean forceOuter)

Description copied from interface: FieldStrategy

Join this value to the class table. Does nothing by default.

Specified by:

join in interface FieldStrategy

joinKey

public Joins joinKey(Joins joins,
                     boolean forceOuter)

Description copied from interface: FieldStrategy

Join the key value to the class table. Does nothing by default.

Specified by:

joinKey in interface FieldStrategy

joinRelation

public Joins joinRelation(Joins joins,
                          boolean forceOuter,
                          boolean traverse)

Description copied from interface: FieldStrategy

Join this value's table to the table for the related first class object type, if any. Does nothing by default.

Specified by:

joinRelation in interface FieldStrategy

traverse - if true, throw proper exception if it is not possible for this mapping to traverse into the related type

joinKeyRelation

public Joins joinKeyRelation(Joins joins,
                             boolean forceOuter,
                             boolean traverse)

Description copied from interface: FieldStrategy

Join this value's table to the table for the related first class object key type, if any. Does nothing by default.

Specified by:

joinKeyRelation in interface FieldStrategy

traverse - if true, throw proper exception if it is not possible for this mapping to traverse into the related type

loadProjection

public Object loadProjection(JDBCStore store,
                             JDBCFetchConfiguration fetch,
                             Result res,
                             Joins joins)
                      throws SQLException

Description copied from interface: FieldStrategy

Load this field value using the given result. The result will contain the columns from ValueMapping.getColumns().

Specified by:

loadProjection in interface FieldStrategy

Throws:

SQLException

loadKeyProjection

public Object loadKeyProjection(JDBCStore store,
                                JDBCFetchConfiguration fetch,
                                Result res,
                                Joins joins)
                         throws SQLException

Description copied from interface: FieldStrategy

Load this field's key value using the given result. The result will contain the columns from ValueMapping.getColumns().

Specified by:

loadKeyProjection in interface FieldStrategy

Throws:

SQLException

isVersionable

public boolean isVersionable()

Description copied from interface: FieldStrategy

Return true if this field can be used as part of a state image for optimistic locking.

Specified by:

isVersionable in interface FieldStrategy

where

public void where(OpenJPAStateManager sm,
                  JDBCStore store,
                  RowManager rm,
                  Object prevValue)
           throws SQLException

Description copied from interface: FieldStrategy

Add a WHERE condition to the row for this field such that the field's current DB value must equal the given previous value. Only versionable mappings must implement this method meaningfully.

Specified by:

where in interface FieldStrategy

Throws:

SQLException