/*******************************************************************************
* Copyright (c) 1998, 2009 Oracle. All rights reserved.
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v1.0 and Eclipse Distribution License v. 1.0
* which accompanies this distribution.
* The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v10.html
* and the Eclipse Distribution License is available at
* http://www.eclipse.org/org/documents/edl-v10.php.
*
* Contributors:
* Oracle - initial API and implementation from Oracle TopLink
* 05/16/2008-1.0M8 Guy Pelletier
* - 218084: Implement metadata merging functionality between mapping files
* 09/23/2008-1.1 Guy Pelletier
* - 241651: JPA 2.0 Access Type support
* 12/12/2008-1.1 Guy Pelletier
* - 249860: Implement table per class inheritance support.
* 02/06/2009-2.0 Guy Pelletier
* - 248293: JPA 2.0 Element Collections (part 2)
* 03/27/2009-2.0 Guy Pelletier
* - 241413: JPA 2.0 Add EclipseLink support for Map type attributes
* 06/02/2009-2.0 Guy Pelletier
* - 278768: JPA 2.0 Association Override Join Table
******************************************************************************/
package org.eclipse.persistence.internal.jpa.metadata.accessors.mappings;
import java.util.List;
import java.util.Map;
import org.eclipse.persistence.exceptions.ValidationException;
import org.eclipse.persistence.internal.jpa.metadata.accessors.classes.ClassAccessor;
import org.eclipse.persistence.internal.jpa.metadata.accessors.objects.MetadataAccessibleObject;
import org.eclipse.persistence.internal.jpa.metadata.accessors.objects.MetadataAnnotation;
import org.eclipse.persistence.internal.jpa.metadata.columns.AssociationOverrideMetadata;
import org.eclipse.persistence.internal.jpa.metadata.columns.JoinColumnMetadata;
import org.eclipse.persistence.internal.jpa.metadata.MetadataDescriptor;
import org.eclipse.persistence.internal.jpa.metadata.MetadataLogger;
import org.eclipse.persistence.internal.helper.DatabaseField;
import org.eclipse.persistence.internal.helper.Helper;
import org.eclipse.persistence.mappings.EmbeddableMapping;
import org.eclipse.persistence.mappings.ManyToManyMapping;
import org.eclipse.persistence.mappings.OneToManyMapping;
import org.eclipse.persistence.mappings.OneToOneMapping;
import org.eclipse.persistence.mappings.UnidirectionalOneToManyMapping;
/**
* INTERNAL:
* A OneToMany relationship accessor. A OneToMany annotation currently is not
* required to be on the accessible object, that is, a 1-M can default.
*
* @author Guy Pelletier
* @since TopLink EJB 3.0 Reference Implementation
*/
public class OneToManyAccessor extends CollectionAccessor {
/**
* INTERNAL:
* Used for OX mapping.
*/
public OneToManyAccessor() {
super("<one-to-many>");
}
/**
* INTERNAL:
*/
public OneToManyAccessor(MetadataAnnotation oneToMany, MetadataAccessibleObject accessibleObject, ClassAccessor classAccessor) {
super(oneToMany, accessibleObject, classAccessor);
// A one to many mapping can default.
if (oneToMany != null) {
setOrphanRemoval((Boolean) oneToMany.getAttribute("orphanRemoval"));
}
}
/**
* INTERNAL:
*
* Return the logging context for this accessor.
*/
protected String getLoggingContext() {
return MetadataLogger.ONE_TO_MANY_MAPPING_REFERENCE_CLASS;
}
/**
* INTERNAL:
*/
@Override
public boolean isOneToMany() {
return true;
}
/**
* INTERNAL:
* Process an OneToMany accessor into an EclipseLink OneToManyMapping. If a
* JoinTable is found however, we must create a ManyToManyMapping.
*/
@Override
public void process() {
super.process();
if (getMappedBy() == null || getMappedBy().equals("")) {
if (getJoinColumns().isEmpty()) {
// No join columns and no mapped by value, default to
// unidirectional 1-M using a M-M mapping and a join table.
processManyToManyMapping();
} else {
// If we find join column(s) then process a uni-directional 1-M.
processUnidirectionalOneToManyMapping();
}
} else {
// Process a 1-M using the mapped by mapping values.
processOneToManyMapping();
}
}
/**
* INTERNAL:
* Process an association override for either an embedded object mapping,
* or a map mapping (element-collection, 1-M and M-M) containing an
* embeddable object as the value or key.
*/
@Override
protected void processAssociationOverride(AssociationOverrideMetadata associationOverride, EmbeddableMapping embeddableMapping, MetadataDescriptor owningDescriptor) {
if (getMapping().isUnidirectionalOneToManyMapping()) {
// Create an override mapping and process the join columns to it.
UnidirectionalOneToManyMapping overrideMapping = new UnidirectionalOneToManyMapping();
overrideMapping.setAttributeName(getAttributeName());
processUnidirectionalOneToManyTargetForeignKeyRelationship(overrideMapping, associationOverride.getJoinColumns(), owningDescriptor);
// The override mapping will have the correct source, sourceRelation,
// target and targetRelation keys. Along with the correct relation table.
embeddableMapping.addOverrideUnidirectionalOneToManyMapping(overrideMapping);
} else {
super.processAssociationOverride(associationOverride, embeddableMapping, owningDescriptor);
}
}
/**
* INTERNAL:
* Process an many to many mapping for this accessor since a join table
* was specified.
*/
protected void processManyToManyMapping() {
// Create a M-M mapping and process common collection mapping metadata
// first followed by specific metadata.
ManyToManyMapping mapping = new ManyToManyMapping();
process(mapping);
// Process the JoinTable metadata.
processJoinTable(mapping, getJoinTableMetadata());
}
/**
* INTERNAL:
* Process an one to many mapping for this accessor.
*/
protected void processOneToManyMapping() {
// Create a 1-M mapping and process common collection mapping metadata
// first followed by specific metadata.
OneToManyMapping mapping = new OneToManyMapping();
process(mapping);
// Non-owning side, process the foreign keys from the owner.
OneToOneMapping ownerMapping = null;
if (getOwningMapping(getMappedBy()).isOneToOneMapping()){
ownerMapping = (OneToOneMapping) getOwningMapping(getMappedBy());
} else {
// If improper mapping encountered, throw an exception.
throw ValidationException.invalidMapping(getJavaClass(), getReferenceClass());
}
Map<DatabaseField, DatabaseField> keys = ownerMapping.getSourceToTargetKeyFields();
for (DatabaseField fkField : keys.keySet()) {
DatabaseField pkField = keys.get(fkField);
// If we are within a table per class strategy we have to update
// the primary key field to point to our own database table.
// The extra table check is if the mapping is actually defined
// on our java class (meaning we have the right table at this
// point and can avoid the cloning)
if (getDescriptor().usesTablePerClassInheritanceStrategy() && ! pkField.getTable().equals(getDescriptor().getPrimaryTable())) {
// We need to update the pk field to be to our table.
pkField = (DatabaseField) pkField.clone();
pkField.setTable(getDescriptor().getPrimaryTable());
}
mapping.addTargetForeignKeyField(fkField, pkField);
}
}
/**
* INTERNAL:
* Process an unidirectional one to many mapping for this accessor since
* join columns were specified and no mapped by value.
*/
protected void processUnidirectionalOneToManyMapping() {
// Create a 1-M unidirectional mapping and process common collection
// mapping metadata first followed by specific metadata.
UnidirectionalOneToManyMapping mapping = new UnidirectionalOneToManyMapping();
process(mapping);
// Process the JoinColumn metadata.
processUnidirectionalOneToManyTargetForeignKeyRelationship(mapping, getJoinColumns(getJoinColumns(), getReferenceDescriptor()), getOwningDescriptor());
}
/**
* INTERNAL:
* Process the join column(s) metadata for the owning side of a
* unidirectional one to many mapping. The default pk used only with single
* primary key entities. The processor should never get as far as to use
* them with entities that have a composite primary key (validation
* exception will be thrown).
*/
protected void processUnidirectionalOneToManyTargetForeignKeyRelationship(UnidirectionalOneToManyMapping mapping, List<JoinColumnMetadata> joinColumns, MetadataDescriptor owningDescriptor) {
// If the pk field (name) is not specified, it
// defaults to the primary key of the source table.
String defaultPKFieldName = owningDescriptor.getPrimaryKeyFieldName();
// If the fk field (name) is not specified, it defaults to the
// concatenation of the following: the name of the referencing
// relationship property or field of the referencing entity; "_";
// the name of the referenced primary key column.
String defaultFKFieldName = getDefaultAttributeName() + "_" + defaultPKFieldName;
// Join columns will come from a @JoinColumn(s).
// Add the source foreign key fields to the mapping.
for (JoinColumnMetadata joinColumn : joinColumns) {
DatabaseField pkField = joinColumn.getPrimaryKeyField();
pkField.setName(getName(pkField, defaultPKFieldName, MetadataLogger.PK_COLUMN), Helper.getDefaultStartDatabaseDelimiter(), Helper.getDefaultEndDatabaseDelimiter());
if (useDelimitedIdentifier()){
pkField.setUseDelimiters(useDelimitedIdentifier());
}
pkField.setTable(owningDescriptor.getPrimaryKeyTable());
DatabaseField fkField = joinColumn.getForeignKeyField();
fkField.setName(getName(fkField, defaultFKFieldName, MetadataLogger.FK_COLUMN), Helper.getDefaultStartDatabaseDelimiter(), Helper.getDefaultEndDatabaseDelimiter());
if (useDelimitedIdentifier()){
fkField.setUseDelimiters(useDelimitedIdentifier());
}
// Set the table name if one is not already set.
if (fkField.getTableName().equals("")) {
fkField.setTable(getReferenceDescriptor().getPrimaryTable());
}
// Uni-directional 12M mapping would like a type on the foreign key
// field. If one is not set, a unidirectional one to many mapping
// will try to set one itself in its postInitialize. There is
// currently a bug against this since the postInitiaze does not
// handle the fact that the descriptor may be an aggregate, hence
// not be able to look up a primary key mapping correctly.
// From a metadata processing standpoint, we'll attempt to make sure
// one is set. Meaning in some cases we won't be able to if we don't
// have an associated mapping accessor for the pkField. So why
// wouldn't we? One, it could be a bogus field specified only for
// testing purposes to ensure an override is correctly applied and
// two, the field could be part of a derived id (which at this point
// we don't have the mapping accessor readily accessible. (may be
// able to fix this if it becomes a problem). And thirdly, there is
// the 'off' chance we've screwed up metadata processing somewhere
// ( yeah right! ) so instead of show casing our mistakes, let's
// hide them! :-) Anyway, long story short, if there is no
// mappingAccessor for the pkField, don't do anything and silently
// continue. Best we can do right now ...
MappingAccessor mappingAccessor = owningDescriptor.getPrimaryKeyAccessorForField(pkField);
if (mappingAccessor != null) {
// If the mapping specified a converter then the field
// classification may be set so check it first.
Class fieldClassification = mappingAccessor.getMapping().getFieldClassification(mappingAccessor.getMapping().getField());
String typeName;
if (fieldClassification == null) {
// No fieldClassification, use the raw class from the
// mapping accessor.
typeName = mappingAccessor.getRawClass().getName();
} else {
typeName = fieldClassification.getName();
}
fkField.setTypeName(typeName);
}
// Add target foreign key to the mapping.
mapping.addTargetForeignKeyField(fkField, pkField);
// If any of the join columns is marked read-only then set the
// mapping to be read only.
if (fkField.isReadOnly()) {
mapping.setIsReadOnly(true);
}
}
}
}