oracle.toplink.essentials.mappings.OneToOneMapping Maven / Gradle / Ivy
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*
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// Copyright (c) 1998, 2006, Oracle. All rights reserved.
package oracle.toplink.essentials.mappings;
import java.util.*;
import oracle.toplink.essentials.exceptions.*;
import oracle.toplink.essentials.expressions.*;
import oracle.toplink.essentials.internal.expressions.ObjectExpression;
import oracle.toplink.essentials.internal.helper.*;
import oracle.toplink.essentials.internal.sessions.*;
import oracle.toplink.essentials.sessions.DatabaseRecord;
import oracle.toplink.essentials.queryframework.*;
import oracle.toplink.essentials.internal.sessions.AbstractRecord;
import oracle.toplink.essentials.internal.sessions.AbstractSession;
import oracle.toplink.essentials.descriptors.ClassDescriptor;
import oracle.toplink.essentials.internal.queryframework.JoinedAttributeManager;
/**
* Purpose: One to one mappings are used to represent a pointer references
* between two java objects. This mappings is usually represented by a single pointer
* (stored in an instance variable) between the source and target objects. In the relational
* database tables, these mappings are normally implemented using foreign keys.
*
* @author Sati
* @since TOPLink/Java 1.0
*/
public class OneToOneMapping extends ObjectReferenceMapping implements RelationalMapping {
/** Maps the source foreign/primary key fields to the target primary/foreign key fields. */
protected Map sourceToTargetKeyFields;
/** Maps the target primary/foreign key fields to the source foreign/primary key fields. */
protected Map targetToSourceKeyFields;
/** Keeps track of which fields are foreign keys on a per field basis (can have mixed foreign key relationships). */
/** These are used for non-unit of work modification to check if the value of the 1-1 was changed and a deletion is required. */
protected boolean shouldVerifyDelete;
protected transient Expression privateOwnedCriteria;
/** Indicates whether the referenced object should always be joined on read queries. */
protected boolean usesJoining;
/* Used internally for EJB 3.0 XML overrides - indicates the fk field name for a join-column */
private String xmlFKNameAttribute;
/* Used internally for EJB 3.0 XML overrides - indicates the pk field name for a join-column */
private String xmlPKNameAttribute;
/**
* PUBLIC:
* Default constructor.
*/
public OneToOneMapping() {
this.selectionQuery = new ReadObjectQuery();
this.sourceToTargetKeyFields = new HashMap(2);
this.targetToSourceKeyFields = new HashMap(2);
this.foreignKeyFields = oracle.toplink.essentials.internal.helper.NonSynchronizedVector.newInstance(1);
this.isForeignKeyRelationship = false;
this.shouldVerifyDelete = true;
this.usesJoining = false;
}
/**
* INTERNAL:
*/
public boolean isRelationalMapping() {
return true;
}
/**
* PUBLIC:
* Define the foreign key relationship in the 1-1 mapping.
* This method is used for composite foreign key relationships,
* that is the source object's table has multiple foreign key fields to
* the target object's primary key fields.
* Both the source foreign key field and the target foreign key field must
* be specified.
* When a foreign key is specified TopLink will automatically populate the
* value for that field from the target object when the object is written to
* the database. If the foreign key is also mapped through a direct-to-field
* then the direct-to-field must be set read-only.
*/
public void addForeignKeyField(DatabaseField sourceForeignKeyField, DatabaseField targetPrimaryKeyField) {
setIsForeignKeyRelationship(true);
getForeignKeyFields().addElement(sourceForeignKeyField);
getSourceToTargetKeyFields().put(sourceForeignKeyField, targetPrimaryKeyField);
getTargetToSourceKeyFields().put(targetPrimaryKeyField, sourceForeignKeyField);
}
/**
* PUBLIC:
* Define the foreign key relationship in the 1-1 mapping.
* This method is used for composite foreign key relationships,
* that is the source object's table has multiple foreign key fields to
* the target object's primary key fields.
* Both the source foreign key field name and the target foreign key field
* name must be specified.
* When a foreign key is specified TopLink will automatically populate the
* value for that field from the target object when the object is written to
* the database. If the foreign key is also mapped through a direct-to-field
* then the direct-to-field must be set read-only.
*/
public void addForeignKeyFieldName(String sourceForeignKeyFieldName, String targetPrimaryKeyFieldName) {
addForeignKeyField(new DatabaseField(sourceForeignKeyFieldName), new DatabaseField(targetPrimaryKeyFieldName));
}
/**
* PUBLIC:
* Define the target foreign key relationship in the 1-1 mapping.
* This method is used for composite target foreign key relationships,
* that is the target object's table has multiple foreign key fields to
* the source object's primary key fields.
* Both the target foreign key field and the source primary key field must
* be specified.
* The distinction between a foreign key and target foreign key is that the
* 1-1 mapping will not populate the target foreign key value when written
* (because it is in the target table). Normally 1-1's are through foreign
* keys but in bi-directional 1-1's the back reference will be a target
* foreign key. In obscure composite legacy data models a 1-1 may consist of
* a foreign key part and a target foreign key part, in this case both
* method will be called with the correct parts.
*/
public void addTargetForeignKeyField(DatabaseField targetForeignKeyField, DatabaseField sourcePrimaryKeyField) {
getSourceToTargetKeyFields().put(sourcePrimaryKeyField, targetForeignKeyField);
getTargetToSourceKeyFields().put(targetForeignKeyField, sourcePrimaryKeyField);
}
/**
* PUBLIC:
* Define the target foreign key relationship in the 1-1 mapping.
* This method is used for composite target foreign key relationships,
* that is the target object's table has multiple foreign key fields to
* the source object's primary key fields.
* Both the target foreign key field name and the source primary key field
* name must be specified.
* The distinction between a foreign key and target foreign key is that the
* 1-1 mapping will not populate the target foreign key value when written
* (because it is in the target table). Normally 1-1's are through foreign
* keys but in bi-directional 1-1's the back reference will be a target
* foreign key. In obscure composite legacy data models a 1-1 may consist of
* a foreign key part and a target foreign key part, in this case both
* method will be called with the correct parts.
*/
public void addTargetForeignKeyFieldName(String targetForeignKeyFieldName, String sourcePrimaryKeyFieldName) {
addTargetForeignKeyField(new DatabaseField(targetForeignKeyFieldName), new DatabaseField(sourcePrimaryKeyFieldName));
}
/**
* INTERNAL:
* Used to allow object level comparisons.
*/
public Expression buildObjectJoinExpression(Expression expression, Object value, AbstractSession session) {
Expression base = ((oracle.toplink.essentials.internal.expressions.ObjectExpression)expression).getBaseExpression();
Expression foreignKeyJoin = null;
// Allow for equal null.
if (value == null) {
// Can only perform null comparison on foreign key relationships.
// It does not really make sense for target any way as it is the source key.
if (!isForeignKeyRelationship()) {
throw QueryException.cannotCompareTargetForeignKeysToNull(base, value, this);
}
for (Iterator sourceFieldsEnum = getSourceToTargetKeyFields().keySet().iterator();
sourceFieldsEnum.hasNext();) {
DatabaseField field = (DatabaseField)sourceFieldsEnum.next();
Expression join = null;
if (expression.isObjectExpression() && ((ObjectExpression)expression).shouldUseOuterJoin()){
join = base.getField(field).equalOuterJoin(null);
} else {
join = base.getField(field).equal(null);
}
if (foreignKeyJoin == null) {
foreignKeyJoin = join;
} else {
foreignKeyJoin = foreignKeyJoin.and(join);
}
}
} else {
if (!getReferenceDescriptor().getJavaClass().isInstance(value)) {
throw QueryException.incorrectClassForObjectComparison(base, value, this);
}
Enumeration keyEnum = extractKeyFromReferenceObject(value, session).elements();
for (Iterator sourceFieldsEnum = getSourceToTargetKeyFields().keySet().iterator();
sourceFieldsEnum.hasNext();) {
DatabaseField field = (DatabaseField)sourceFieldsEnum.next();
Expression join = null;
if (expression.isObjectExpression() && ((ObjectExpression)expression).shouldUseOuterJoin()){
join = base.getField(field).equalOuterJoin(keyEnum.nextElement());
} else {
join = base.getField(field).equal(keyEnum.nextElement());
}
if (foreignKeyJoin == null) {
foreignKeyJoin = join;
} else {
foreignKeyJoin = foreignKeyJoin.and(join);
}
}
}
return foreignKeyJoin;
}
/**
* INTERNAL:
* Used to allow object level comparisons.
*/
public Expression buildObjectJoinExpression(Expression expression, Expression argument, AbstractSession session) {
Expression base = ((oracle.toplink.essentials.internal.expressions.ObjectExpression)expression).getBaseExpression();
Expression foreignKeyJoin = null;
Iterator targetFieldsEnum = getSourceToTargetKeyFields().values().iterator();
for (Iterator sourceFieldsEnum = getSourceToTargetKeyFields().keySet().iterator();
sourceFieldsEnum.hasNext();) {
DatabaseField sourceField = (DatabaseField)sourceFieldsEnum.next();
DatabaseField targetField = (DatabaseField)targetFieldsEnum.next();
Expression join = null;
if (expression.isObjectExpression() && ((ObjectExpression)expression).shouldUseOuterJoin()){
join = base.getField(sourceField).equalOuterJoin(argument.getField(targetField));
} else {
join = base.getField(sourceField).equal(argument.getField(targetField));
}
if (foreignKeyJoin == null) {
foreignKeyJoin = join;
} else {
foreignKeyJoin = foreignKeyJoin.and(join);
}
}
return foreignKeyJoin;
}
/**
* INTERNAL:
* This methods clones all the fields and ensures that each collection refers to
* the same clones.
*/
public Object clone() {
OneToOneMapping clone = (OneToOneMapping)super.clone();
clone.setForeignKeyFields(oracle.toplink.essentials.internal.helper.NonSynchronizedVector.newInstance(getForeignKeyFields().size()));
clone.setSourceToTargetKeyFields(new HashMap(getSourceToTargetKeyFields().size()));
clone.setTargetToSourceKeyFields(new HashMap(getTargetToSourceKeyFields().size()));
Hashtable setOfFields = new Hashtable(getTargetToSourceKeyFields().size());
//clone foreign keys and save the clones in a set
for (Enumeration enumtr = getForeignKeyFields().elements(); enumtr.hasMoreElements();) {
DatabaseField field = (DatabaseField)enumtr.nextElement();
DatabaseField fieldClone = (DatabaseField)field.clone();
setOfFields.put(field, fieldClone);
clone.getForeignKeyFields().addElement(fieldClone);
}
//get clones from set for source hashtable. If they do not exist, create a new one.
for (Iterator sourceEnum = getSourceToTargetKeyFields().keySet().iterator();
sourceEnum.hasNext();) {
DatabaseField sourceField = (DatabaseField)sourceEnum.next();
DatabaseField targetField = (DatabaseField)getSourceToTargetKeyFields().get(sourceField);
DatabaseField targetClone;
DatabaseField sourceClone;
targetClone = (DatabaseField)setOfFields.get(targetField);
if (targetClone == null) {
targetClone = (DatabaseField)targetField.clone();
setOfFields.put(targetField, targetClone);
}
sourceClone = (DatabaseField)setOfFields.get(sourceField);
if (sourceClone == null) {
sourceClone = (DatabaseField)sourceField.clone();
setOfFields.put(sourceField, sourceClone);
}
clone.getSourceToTargetKeyFields().put(sourceClone, targetClone);
}
//get clones from set for target hashtable. If they do not exist, create a new one.
for (Iterator targetEnum = getTargetToSourceKeyFields().keySet().iterator();
targetEnum.hasNext();) {
DatabaseField targetField = (DatabaseField)targetEnum.next();
DatabaseField sourceField = (DatabaseField)getTargetToSourceKeyFields().get(targetField);
DatabaseField targetClone;
DatabaseField sourceClone;
targetClone = (DatabaseField)setOfFields.get(targetField);
if (targetClone == null) {
targetClone = (DatabaseField)targetField.clone();
setOfFields.put(targetField, targetClone);
}
sourceClone = (DatabaseField)setOfFields.get(sourceField);
if (sourceClone == null) {
sourceClone = (DatabaseField)sourceField.clone();
setOfFields.put(sourceField, sourceClone);
}
clone.getTargetToSourceKeyFields().put(targetClone, sourceClone);
}
return clone;
}
/**
* PUBLIC:
* Indicates whether the referenced object should always be joined on read queries.
* Joining will join the two classes tables to read all of the data in a single query.
* This should only be used if it is know that the related objects are always required with the source object, or indirection is not used.
*/
public void dontUseJoining() {
setUsesJoining(false);
}
/**
* INTERNAL:
* Extract the foreign key value from the source row.
*/
protected Vector extractForeignKeyFromRow(AbstractRecord row, AbstractSession session) {
Vector key = new Vector();
for (Iterator fieldEnum = getSourceToTargetKeyFields().keySet().iterator();
fieldEnum.hasNext();) {
DatabaseField field = (DatabaseField)fieldEnum.next();
Object value = row.get(field);
// Must ensure the classificatin to get a cache hit.
try {
value = session.getDatasourcePlatform().getConversionManager().convertObject(value, getDescriptor().getObjectBuilder().getFieldClassification(field));
} catch (ConversionException e) {
throw ConversionException.couldNotBeConverted(this, getDescriptor(), e);
}
key.addElement(value);
}
return key;
}
/**
* INTERNAL:
* Extract the key value from the reference object.
*/
protected Vector extractKeyFromReferenceObject(Object object, AbstractSession session) {
Vector key = new Vector();
for (Iterator fieldEnum = getSourceToTargetKeyFields().values().iterator();
fieldEnum.hasNext();) {
DatabaseField field = (DatabaseField)fieldEnum.next();
if (object == null) {
key.addElement(null);
} else {
key.addElement(getReferenceDescriptor().getObjectBuilder().extractValueFromObjectForField(object, field, session));
}
}
return key;
}
/**
* INTERNAL:
* Return the primary key for the reference object (i.e. the object
* object referenced by domainObject and specified by mapping).
* This key will be used by a RemoteValueHolder.
*/
public Vector extractPrimaryKeysForReferenceObjectFromRow(AbstractRecord row) {
List primaryKeyFields = getReferenceDescriptor().getPrimaryKeyFields();
Vector result = new Vector(primaryKeyFields.size());
for (int index = 0; index < primaryKeyFields.size(); index++) {
DatabaseField targetKeyField = (DatabaseField)primaryKeyFields.get(index);
DatabaseField sourceKeyField = (DatabaseField)getTargetToSourceKeyFields().get(targetKeyField);
if (sourceKeyField == null) {
return new Vector(1);
}
result.addElement(row.get(sourceKeyField));
}
return result;
}
/**
* INTERNAL:
* Return the classifiction for the field contained in the mapping.
* This is used to convert the row value to a consistent java value.
*/
public Class getFieldClassification(DatabaseField fieldToClassify) throws DescriptorException {
DatabaseField fieldInTarget = (DatabaseField)getSourceToTargetKeyFields().get(fieldToClassify);
if (fieldInTarget == null) {
return null;// Can be registered as multiple table secondary field mapping
}
DatabaseMapping mapping = getReferenceDescriptor().getObjectBuilder().getMappingForField(fieldInTarget);
if (mapping == null) {
return null;// Means that the mapping is read-only
}
return mapping.getFieldClassification(fieldInTarget);
}
/**
* PUBLIC:
* Return the foreign key field names associated with the mapping.
* These are only the source fields that are writable.
*/
public Vector getForeignKeyFieldNames() {
Vector fieldNames = new Vector(getForeignKeyFields().size());
for (Enumeration fieldsEnum = getForeignKeyFields().elements();
fieldsEnum.hasMoreElements();) {
fieldNames.addElement(((DatabaseField)fieldsEnum.nextElement()).getQualifiedName());
}
return fieldNames;
}
/**
* Return the appropriate hashtable that maps the "foreign keys"
* to the "primary keys".
*/
protected Map getForeignKeysToPrimaryKeys() {
if (this.isForeignKeyRelationship()) {
return this.getSourceToTargetKeyFields();
} else {
return this.getTargetToSourceKeyFields();
}
}
/**
* INTERNAL:
* Return a vector of the foreign key fields in the same order
* as the corresponding primary key fields are in their descriptor.
*/
public Vector getOrderedForeignKeyFields() {
List primaryKeyFields = getPrimaryKeyDescriptor().getPrimaryKeyFields();
Vector result = new Vector(primaryKeyFields.size());
for (int index = 0; index < primaryKeyFields.size(); index++) {
DatabaseField pkField = (DatabaseField)primaryKeyFields.get(index);
boolean found = false;
for (Iterator fkStream = this.getForeignKeysToPrimaryKeys().keySet().iterator();
fkStream.hasNext();) {
DatabaseField fkField = (DatabaseField)fkStream.next();
if (this.getForeignKeysToPrimaryKeys().get(fkField).equals(pkField)) {
found = true;
result.addElement(fkField);
break;
}
}
if (!found) {
throw DescriptorException.missingForeignKeyTranslation(this, pkField);
}
}
return result;
}
/**
* Return the descriptor for whichever side of the
* relation has the "primary key".
*/
protected ClassDescriptor getPrimaryKeyDescriptor() {
if (this.isForeignKeyRelationship()) {
return this.getReferenceDescriptor();
} else {
return this.getDescriptor();
}
}
/**
* INTERNAL:
* The private owned criteria is only used outside of the unit of work to compare the previous value of the reference.
*/
public Expression getPrivateOwnedCriteria() {
if (privateOwnedCriteria == null) {
initializePrivateOwnedCriteria();
}
return privateOwnedCriteria;
}
/**
* INTERNAL:
* Return a collection of the source to target field value associations.
*/
public Vector getSourceToTargetKeyFieldAssociations() {
Vector associations = new Vector(getSourceToTargetKeyFields().size());
Iterator sourceFieldEnum = getSourceToTargetKeyFields().keySet().iterator();
Iterator targetFieldEnum = getSourceToTargetKeyFields().values().iterator();
while (sourceFieldEnum.hasNext()) {
Object fieldValue = ((DatabaseField)sourceFieldEnum.next()).getQualifiedName();
Object attributeValue = ((DatabaseField)targetFieldEnum.next()).getQualifiedName();
associations.addElement(new Association(fieldValue, attributeValue));
}
return associations;
}
/**
* INTERNAL:
* Returns the source keys to target keys fields association.
*/
public Map getSourceToTargetKeyFields() {
return sourceToTargetKeyFields;
}
/**
* INTERNAL:
* Returns the target keys to source keys fields association.
*/
public Map getTargetToSourceKeyFields() {
return targetToSourceKeyFields;
}
/**
* INTERNAL:
* For internal use only: used for EJB 3.0 XML overrides. This method returns
* the foreign key field name as defined the associated join-column element
* in an XML instance document.
*/
public String getXMLFKNameAttribute() {
if (xmlFKNameAttribute == null) {
xmlFKNameAttribute = "";
}
return xmlFKNameAttribute;
}
/**
* INTERNAL:
* For internal use only: used for EJB 3.0 XML overrides. This method returns
* the primary key field name as defined the associated join-column element
* in an XML instance document.
*/
public String getXMLPKNameAttribute() {
if (xmlPKNameAttribute == null) {
xmlPKNameAttribute = "";
}
return xmlPKNameAttribute;
}
/**
* INTERNAL:
* Initialize the mapping.
*/
public void initialize(AbstractSession session) throws DescriptorException {
super.initialize(session);
// handle any required non-owning side initialization
if (m_requiresCompletion && !m_mappedBy.equals("")) {
OneToOneMapping ownerMapping = (OneToOneMapping) getReferenceClassDescriptor().getMappingForAttributeName(m_mappedBy);
if (ownerMapping != null) {
setSourceToTargetKeyFields(ownerMapping.getTargetToSourceKeyFields());
setTargetToSourceKeyFields(ownerMapping.getSourceToTargetKeyFields());
}
}
// Must set table of foreign keys.
for (Enumeration foreignKeysEnum = getForeignKeyFields().elements();
foreignKeysEnum.hasMoreElements();) {
DatabaseField foreignKeyField = (DatabaseField)foreignKeysEnum.nextElement();
getDescriptor().buildField(foreignKeyField);
}
// If only a selection criteria is specified then the foreign keys do not have to be initialized.
if (!(getTargetToSourceKeyFields().isEmpty() && getSourceToTargetKeyFields().isEmpty())) {
if (getTargetToSourceKeyFields().isEmpty() || getSourceToTargetKeyFields().isEmpty()) {
initializeForeignKeysWithDefaults(session);
} else {
initializeForeignKeys(session);
}
}
if (shouldInitializeSelectionCriteria()) {
initializeSelectionCriteria(session);
} else {
setShouldVerifyDelete(false);
}
setFields(collectFields());
}
/**
* INTERNAL:
* The foreign keys primary keys are stored as database fields in the hashtable.
*/
protected void initializeForeignKeys(AbstractSession session) {
Iterator sourceEnum = getSourceToTargetKeyFields().keySet().iterator();
Iterator targetEnum = getTargetToSourceKeyFields().keySet().iterator();
while (sourceEnum.hasNext()) {
DatabaseField sourceField = (DatabaseField)sourceEnum.next();
DatabaseField targetField = (DatabaseField)targetEnum.next();
getDescriptor().buildField(sourceField);
getReferenceDescriptor().buildField(targetField);
}
}
/**
* INTERNAL:
* The foreign keys primary keys are stored as database fields in the hashtable.
*/
protected void initializeForeignKeysWithDefaults(AbstractSession session) {
if (isForeignKeyRelationship()) {
if (getSourceToTargetKeyFields().size() != 1) {
throw DescriptorException.foreignKeysDefinedIncorrectly(this);
}
List targetKeys = getReferenceDescriptor().getPrimaryKeyFields();
if (targetKeys.size() != 1) {
//target and source keys are not the same size.
throw DescriptorException.sizeMismatchOfForeignKeys(this);
}
//grab the only element out of the Hashtable
DatabaseField sourceField = (DatabaseField)getSourceToTargetKeyFields().keySet().iterator().next();
getDescriptor().buildField(sourceField);
getSourceToTargetKeyFields().put(sourceField, targetKeys.get(0));
getTargetToSourceKeyFields().put(targetKeys.get(0), sourceField);
} else {
if (getTargetToSourceKeyFields().size() != 1) {
throw DescriptorException.foreignKeysDefinedIncorrectly(this);
}
List sourceKeys = getDescriptor().getPrimaryKeyFields();
if (sourceKeys.size() != 1) {
//target and source keys are not the same size.
throw DescriptorException.sizeMismatchOfForeignKeys(this);
}
//grab the only element out of the Hashtable
DatabaseField targetField = (DatabaseField)getTargetToSourceKeyFields().keySet().iterator().next();
getReferenceDescriptor().buildField(targetField);
getTargetToSourceKeyFields().put(targetField, sourceKeys.get(0));
getSourceToTargetKeyFields().put(sourceKeys.get(0), targetField);
}
}
/**
* INTERNAL:
* Selection criteria is created with source foreign keys and target keys.
*/
protected void initializePrivateOwnedCriteria() {
if (!isForeignKeyRelationship()) {
setPrivateOwnedCriteria(getSelectionCriteria());
} else {
Expression pkCriteria = getDescriptor().getObjectBuilder().getPrimaryKeyExpression();
ExpressionBuilder builder = new ExpressionBuilder();
Expression backRef = builder.getManualQueryKey(getAttributeName() + "-back-ref", getDescriptor());
Expression newPKCriteria = pkCriteria.rebuildOn(backRef);
Expression twistedSelection = backRef.twist(getSelectionCriteria(), builder);
if (getDescriptor().getQueryManager().getAdditionalJoinExpression() != null) {
// We don't have to twist the additional join because it's all against the same node, which is our base
// but we do have to rebuild it onto the manual query key
Expression rebuiltAdditional = getDescriptor().getQueryManager().getAdditionalJoinExpression().rebuildOn(backRef);
if (twistedSelection == null) {
twistedSelection = rebuiltAdditional;
} else {
twistedSelection = twistedSelection.and(rebuiltAdditional);
}
}
setPrivateOwnedCriteria(newPKCriteria.and(twistedSelection));
}
}
/**
* INTERNAL:
* Selection criteria is created with source foreign keys and target keys.
* This criteria is then used to read target records from the table.
*
* CR#3922 - This method is almost the same as buildSelectionCriteria() the difference
* is that getSelectionCriteria() is called
*/
protected void initializeSelectionCriteria(AbstractSession session) {
if (getSourceToTargetKeyFields().isEmpty()) {
throw DescriptorException.noForeignKeysAreSpecified(this);
}
Expression criteria;
Expression builder = new ExpressionBuilder();
for (Iterator entries = getSourceToTargetKeyFields().entrySet().iterator(); entries.hasNext();) {
Map.Entry entry = (Map.Entry) entries.next();
DatabaseField foreignKey = (DatabaseField)entry.getKey();
DatabaseField targetKey = (DatabaseField)entry.getValue();
Expression expression = builder.getField(targetKey).equal(builder.getParameter(foreignKey));
criteria = expression.and(getSelectionCriteria());
setSelectionCriteria(criteria);
}
}
/**
* This method would allow customers to get the potential selection criteria for a mapping
* prior to initialization. This would allow them to more easily create an ammendment method
* that would ammend the SQL for the join.
*
* CR#3922 - This method is almost the same as initializeSelectionCriteria() the difference
* is that getSelectionCriteria() is not called
*/
public Expression buildSelectionCriteria() {
// CR3922
if (getSourceToTargetKeyFields().isEmpty()) {
throw DescriptorException.noForeignKeysAreSpecified(this);
}
Expression criteria = null;
Expression builder = new ExpressionBuilder();
for (Iterator keys = getSourceToTargetKeyFields().keySet().iterator(); keys.hasNext();) {
DatabaseField foreignKey = (DatabaseField)keys.next();
DatabaseField targetKey = (DatabaseField)getSourceToTargetKeyFields().get(foreignKey);
Expression expression = builder.getField(targetKey).equal(builder.getParameter(foreignKey));
if (criteria == null) {
criteria = expression;
} else {
criteria = expression.and(criteria);
}
}
return criteria;
}
/**
* INTERNAL:
* Builds a shallow original object. Only direct attributes and primary
* keys are populated. In this way the minimum original required for
* instantiating a working copy clone can be built without placing it in
* the shared cache (no concern over cycles).
*/
public void buildShallowOriginalFromRow(AbstractRecord databaseRow, Object original, ObjectBuildingQuery query, AbstractSession executionSession) {
// Now we are only building this original so we can extract the primary
// key out of it. If the primary key is stored accross a 1-1 a value
// holder needs to be built/triggered to get at it.
// In this case recursively build the shallow original accross the 1-1.
// We only need the primary key for that object, and we know
// what that primary key is: it is the foreign key in our row.
ClassDescriptor descriptor = getReferenceDescriptor();
AbstractRecord targetRow = new DatabaseRecord();
for (Iterator keys = getSourceToTargetKeyFields().keySet().iterator(); keys.hasNext();) {
DatabaseField foreignKey = (DatabaseField)keys.next();
DatabaseField targetKey = (DatabaseField)getSourceToTargetKeyFields().get(foreignKey);
targetRow.put(targetKey, databaseRow.get(foreignKey));
}
Object targetObject = descriptor.getObjectBuilder().buildNewInstance();
descriptor.getObjectBuilder().buildAttributesIntoShallowObject(targetObject, databaseRow, query);
targetObject = getIndirectionPolicy().valueFromRow(targetObject);
setAttributeValueInObject(original, targetObject);
}
/**
* INTERNAL:
*/
public boolean isOneToOneMapping() {
return true;
}
/**
* INTERNAL:
* Reads the private owned object.
*/
protected Object readPrivateOwnedForObject(ObjectLevelModifyQuery modifyQuery) throws DatabaseException {
if (modifyQuery.getSession().isUnitOfWork()) {
return super.readPrivateOwnedForObject(modifyQuery);
} else {
if (!shouldVerifyDelete()) {
return null;
}
ReadObjectQuery readQuery = (ReadObjectQuery)getSelectionQuery().clone();
readQuery.setSelectionCriteria(getPrivateOwnedCriteria());
return modifyQuery.getSession().executeQuery(readQuery, modifyQuery.getTranslationRow());
}
}
/**
* INTERNAL:
* Rehash any hashtables based on fields.
* This is used to clone descriptors for aggregates, which hammer field names,
* it is probably better not to hammer the field name and this should be refactored.
*/
public void rehashFieldDependancies(AbstractSession session) {
setSourceToTargetKeyFields(Helper.rehashMap(getSourceToTargetKeyFields()));
}
/**
* PUBLIC:
* Define the foreign key relationship in the 1-1 mapping.
* This method is used for singleton foreign key relationships only,
* that is the source object's table has a foreign key field to
* the target object's primary key field.
* Only the source foreign key field name is specified.
* When a foreign key is specified TopLink will automatically populate the value
* for that field from the target object when the object is written to the database.
* If the foreign key is also mapped through a direct-to-field then the direct-to-field must
* be set read-only.
*/
public void setForeignKeyFieldName(String sourceForeignKeyFieldName) {
DatabaseField sourceField = new DatabaseField(sourceForeignKeyFieldName);
setIsForeignKeyRelationship(true);
getForeignKeyFields().addElement(sourceField);
getSourceToTargetKeyFields().put(sourceField, new DatabaseField());
}
/**
* PUBLIC:
* Return the foreign key field names associated with the mapping.
* These are only the source fields that are writable.
*/
public void setForeignKeyFieldNames(Vector fieldNames) {
Vector fields = oracle.toplink.essentials.internal.helper.NonSynchronizedVector.newInstance(fieldNames.size());
for (Enumeration fieldNamesEnum = fieldNames.elements(); fieldNamesEnum.hasMoreElements();) {
fields.addElement(new DatabaseField((String)fieldNamesEnum.nextElement()));
}
setForeignKeyFields(fields);
}
/**
* INTERNAL:
* Private owned criteria is used to verify the deletion of the target.
* It joins from the source table on the foreign key to the target table,
* with a parameterization of the primary key of the source object.
*/
protected void setPrivateOwnedCriteria(Expression expression) {
privateOwnedCriteria = expression;
}
/**
* PUBLIC:
* Verify delete is used during delete and update on private 1:1's outside of a unit of work only.
* It checks for the previous value of the target object through joining the source and target tables.
* By default it is always done, but may be disabled for performance on distributed database reasons.
* In the unit of work the previous value is obtained from the backup-clone so it is never used.
*/
public void setShouldVerifyDelete(boolean shouldVerifyDelete) {
this.shouldVerifyDelete = shouldVerifyDelete;
}
/**
* INTERNAL:
* Set a collection of the source to target field associations.
*/
public void setSourceToTargetKeyFieldAssociations(Vector sourceToTargetKeyFieldAssociations) {
setSourceToTargetKeyFields(new HashMap(sourceToTargetKeyFieldAssociations.size() + 1));
setTargetToSourceKeyFields(new HashMap(sourceToTargetKeyFieldAssociations.size() + 1));
for (Enumeration associationsEnum = sourceToTargetKeyFieldAssociations.elements();
associationsEnum.hasMoreElements();) {
Association association = (Association)associationsEnum.nextElement();
Object sourceField = new DatabaseField((String)association.getKey());
Object targetField = new DatabaseField((String)association.getValue());
getSourceToTargetKeyFields().put(sourceField, targetField);
getTargetToSourceKeyFields().put(targetField, sourceField);
}
}
/**
* INTERNAL:
* Set the source keys to target keys fields association.
*/
public void setSourceToTargetKeyFields(Map sourceToTargetKeyFields) {
this.sourceToTargetKeyFields = sourceToTargetKeyFields;
}
/**
* PUBLIC:
* Define the target foreign key relationship in the 1-1 mapping.
* This method is used for singleton target foreign key relationships only,
* that is the target object's table has a foreign key field to
* the source object's primary key field.
* The target foreign key field name is specified.
* The distinction between a foreign key and target foreign key is that the 1-1
* mapping will not populate the target foreign key value when written (because it is in the target table).
* Normally 1-1's are through foreign keys but in bi-directional 1-1's
* the back reference will be a target foreign key.
*/
public void setTargetForeignKeyFieldName(String targetForeignKeyFieldName) {
DatabaseField targetField = new DatabaseField(targetForeignKeyFieldName);
getTargetToSourceKeyFields().put(targetField, new DatabaseField());
}
/**
* INTERNAL:
* Set the target keys to source keys fields association.
*/
public void setTargetToSourceKeyFields(Map targetToSourceKeyFields) {
this.targetToSourceKeyFields = targetToSourceKeyFields;
}
/**
* PUBLIC:
* Indicates whether the referenced object should always be joined on read queries.
* Joining will join the two classes tables to read all of the data in a single query.
* This should only be used if it is know that the related objects are always required with the source object, or indirection is not used.
*/
public void setUsesJoining(boolean usesJoining) {
if (usesJoining == this.usesJoining) {
return;
}
this.usesJoining = usesJoining;
// For 3524579 now cache joined mappings on the object builder.
// This allows a user to set joining dynamically after the
// descriptors have been initialized. Generally this is not
// supported, but since we were checking this flag in prepare after
// initialization some degree of backward compatibility should be
// provided.
if (getDescriptor() != null) {
getDescriptor().reInitializeJoinedAttributes();
}
// Still every query which is already prepared, like all selection
// queries, will not pick up this change.
}
/**
* INTERNAL:
* For internal use only: used for EJB 3.0 XML overrides. This method sets
* the foreign key field name as defined the associated join-column element
* in an XML instance document.
*/
public void setXMLFKNameAttribute(String xmlFKNameAttribute) {
this.xmlFKNameAttribute = xmlFKNameAttribute;
}
/**
* INTERNAL:
* For internal use only: used for EJB 3.0 XML overrides. This method sets
* the primary key field name as defined the associated join-column element
* in an XML instance document.
*/
public void setXMLPKNameAttribute(String xmlPKNameAttribute) {
this.xmlPKNameAttribute = xmlPKNameAttribute;
}
/**
* PUBLIC:
* Indicates whether the referenced object should always be joined on read queries.
* Joining will join the two classes tables to read all of the data in a single query.
* This should only be used if it is know that the related objects are always required with the source object, or indirection is not used.
*/
public boolean shouldUseJoining() {
return usesJoining;
}
/**
* PUBLIC:
* Verify delete is used during delete and update outside of a unit of work only.
* It checks for the previous value of the target object through joining the source and target tables.
*/
public boolean shouldVerifyDelete() {
return shouldVerifyDelete;
}
/**
* INTERNAL
* Return true if this mapping supports cascaded version optimistic locking.
*/
public boolean isCascadedLockingSupported() {
return true;
}
/**
* INTERNAL:
* Return if this mapping support joining.
*/
public boolean isJoiningSupported() {
return true;
}
/**
* PUBLIC:
* Indicates whether the referenced object should always be joined on read queries.
* Joining will join the two classes tables to read all of the data in a single query.
* This should only be used if it is know that the related objects are always required with the source object, or indirection is not used.
*/
public void useJoining() {
setUsesJoining(true);
}
/**
* INTERNAL:
* A subclass should implement this method if it wants different behaviour.
* Write the foreign key values from the attribute to the row.
*/
public void writeFromAttributeIntoRow(Object attribute, AbstractRecord row, AbstractSession session)
{
for (Enumeration fieldsEnum = getForeignKeyFields().elements(); fieldsEnum.hasMoreElements();) {
DatabaseField sourceKey = (DatabaseField) fieldsEnum.nextElement();
DatabaseField targetKey = (DatabaseField) getSourceToTargetKeyFields().get(sourceKey);
Object referenceValue = null;
// If privately owned part is null then method cannot be invoked.
if (attribute != null) {
referenceValue = getReferenceDescriptor().getObjectBuilder().extractValueFromObjectForField(attribute, targetKey, session);
}
row.add(sourceKey, referenceValue);
}
}
/**
* INTERNAL:
* Get a value from the object and set that in the respective field of the row.
*/
public Object valueFromObject(Object object, DatabaseField field, AbstractSession session) {
// First check if the value can be obtained from the value holder's row.
AbstractRecord referenceRow = getIndirectionPolicy().extractReferenceRow(getAttributeValueFromObject(object));
if (referenceRow != null) {
Object value = referenceRow.get(field);
// Must ensure the classification to get a cache hit.
try {
value = session.getDatasourcePlatform().convertObject(value, getFieldClassification(field));
} catch (ConversionException e) {
throw ConversionException.couldNotBeConverted(this, getDescriptor(), e);
}
return value;
}
Object referenceObject = getRealAttributeValueFromObject(object, session);
if (referenceObject == null) {
return null;
}
DatabaseField targetField = (DatabaseField)getSourceToTargetKeyFields().get(field);
return getReferenceDescriptor().getObjectBuilder().extractValueFromObjectForField(referenceObject, targetField, session);
}
/**
* INTERNAL:
* If the query used joining or partial attributes, build the target object directly.
*/
protected Object valueFromRowInternalWithJoin(AbstractRecord row, JoinedAttributeManager joinManager, AbstractSession executionSession) throws DatabaseException {
// PERF: Direct variable access.
Object referenceObject;
// CR #... the field for many objects may be in the row,
// so build the subpartion of the row through the computed values in the query,
// this also helps the field indexing match.
AbstractRecord targetRow = trimRowForJoin(row, joinManager, executionSession);
// PERF: Only check for null row if an outer-join was used.
if (joinManager.isAttributeJoined(getDescriptor(), getAttributeName()) && joinManager.hasOuterJoinedAttributeQuery()) {
Vector key = this.referenceDescriptor.getObjectBuilder().extractPrimaryKeyFromRow(targetRow, executionSession);
if (key == null) {
return this.indirectionPolicy.nullValueFromRow();
}
}
// A nested query must be built to pass to the descriptor that looks like the real query execution would,
// these should be cached on the query during prepare.
ObjectLevelReadQuery nestedQuery = null;
if (joinManager.getJoinedMappingQueries_() != null) {
nestedQuery = (ObjectLevelReadQuery) joinManager.getJoinedMappingQueries_().get(this);
} else {
nestedQuery = prepareNestedJoins(joinManager, executionSession);
}
nestedQuery = (ObjectLevelReadQuery)nestedQuery.clone();
nestedQuery.setTranslationRow(targetRow);
nestedQuery.setSession(executionSession);
//CR #4365 - used to prevent infinite recursion on refresh object cascade all
nestedQuery.setQueryId(joinManager.getBaseQuery().getQueryId());
referenceObject = this.referenceDescriptor.getObjectBuilder().buildObject(nestedQuery, targetRow, nestedQuery.getJoinedAttributeManager());
// For bug 3641713 buildObject doesn't wrap if called on a UnitOfWork for performance reasons,
// must wrap here as this is the last time we can look at the query and tell whether to wrap or not.
if (nestedQuery.shouldUseWrapperPolicy() && nestedQuery.getSession().isUnitOfWork()) {
referenceObject = this.referenceDescriptor.getObjectBuilder().wrapObject(referenceObject, nestedQuery.getSession());
}
return this.indirectionPolicy.valueFromRow(referenceObject);
}
/**
* INTERNAL:
* Return the value of the field from the row or a value holder on the query to obtain the object.
* Check for batch + aggregation reading.
*/
protected Object valueFromRowInternal(AbstractRecord row, JoinedAttributeManager joinManager, AbstractSession executionSession) throws DatabaseException {
// If any field in the foreign key is null then it means there are no referenced objects
// Skip for partial objects as fk may not be present.
int size = this.fields.size();
for (int index = 0; index < size; index++) {
DatabaseField field = (DatabaseField)this.fields.get(index);
if (row.get(field) == null) {
return this.indirectionPolicy.nullValueFromRow();
}
}
// Call the default which executes the selection query,
// or wraps the query with a value holder.
return super.valueFromRowInternal(row, joinManager, executionSession);
}
/**
* INTERNAL:
* Get a value from the object and set that in the respective field of the row.
*/
public void writeFromObjectIntoRow(Object object, AbstractRecord databaseRow, AbstractSession session) {
if (isReadOnly() || (!isForeignKeyRelationship())) {
return;
}
AbstractRecord referenceRow = getIndirectionPolicy().extractReferenceRow(getAttributeValueFromObject(object));
if (referenceRow == null) {
// Extract from object.
Object referenceObject = getRealAttributeValueFromObject(object, session);
for (Enumeration fieldsEnum = getForeignKeyFields().elements();
fieldsEnum.hasMoreElements();) {
DatabaseField sourceKey = (DatabaseField)fieldsEnum.nextElement();
DatabaseField targetKey = (DatabaseField)getSourceToTargetKeyFields().get(sourceKey);
Object referenceValue = null;
// If privately owned part is null then method cannot be invoked.
if (referenceObject != null) {
referenceValue = getReferenceDescriptor().getObjectBuilder().extractValueFromObjectForField(referenceObject, targetKey, session);
}
databaseRow.add(sourceKey, referenceValue);
}
} else {
for (Enumeration fieldsEnum = getForeignKeyFields().elements();
fieldsEnum.hasMoreElements();) {
DatabaseField sourceKey = (DatabaseField)fieldsEnum.nextElement();
Object referenceValue = referenceRow.get(sourceKey);
databaseRow.add(sourceKey, referenceValue);
}
}
}
/**
* INTERNAL:
* This row is built for shallow insert which happens in case of bidirectional inserts.
* The foreign keys must be set to null to avoid constraints.
*/
public void writeFromObjectIntoRowForShallowInsert(Object object, AbstractRecord databaseRow, AbstractSession session) {
if (isReadOnly() || (!isForeignKeyRelationship())) {
return;
}
for (Enumeration fieldsEnum = getForeignKeyFields().elements();
fieldsEnum.hasMoreElements();) {
DatabaseField sourceKey = (DatabaseField)fieldsEnum.nextElement();
databaseRow.add(sourceKey, null);
}
}
/**
* INTERNAL:
* Get a value from the object and set that in the respective field of the row.
*/
public void writeFromObjectIntoRowWithChangeRecord(ChangeRecord changeRecord, AbstractRecord databaseRow, AbstractSession session) {
if (isReadOnly() || (!isForeignKeyRelationship())) {
return;
}
// the object must be used here as the foreign key may include more than just the
// primary key of the referenced object and the changeSet may not have the rquired information
Object object = ((ObjectChangeSet)changeRecord.getOwner()).getUnitOfWorkClone();
AbstractRecord referenceRow = getIndirectionPolicy().extractReferenceRow(getAttributeValueFromObject(object));
if (referenceRow == null) {
// Extract from object.
Object referenceObject = getRealAttributeValueFromObject(object, session);
for (Enumeration fieldsEnum = getForeignKeyFields().elements();
fieldsEnum.hasMoreElements();) {
DatabaseField sourceKey = (DatabaseField)fieldsEnum.nextElement();
DatabaseField targetKey = (DatabaseField)getSourceToTargetKeyFields().get(sourceKey);
Object referenceValue = null;
// If privately owned part is null then method cannot be invoked.
if (referenceObject != null) {
referenceValue = getReferenceDescriptor().getObjectBuilder().extractValueFromObjectForField(referenceObject, targetKey, session);
}
databaseRow.add(sourceKey, referenceValue);
}
} else {
for (Enumeration fieldsEnum = getForeignKeyFields().elements();
fieldsEnum.hasMoreElements();) {
DatabaseField sourceKey = (DatabaseField)fieldsEnum.nextElement();
Object referenceValue = referenceRow.get(sourceKey);
databaseRow.add(sourceKey, referenceValue);
}
}
}
/**
* INTERNAL:
* This row is built for shallow insert which happens in case of bidirectional inserts.
* The foreign keys must be set to null to avoid constraints.
*/
public void writeFromObjectIntoRowForShallowInsertWithChangeRecord(ChangeRecord ChangeRecord, AbstractRecord databaseRow, AbstractSession session) {
if (isReadOnly() || (!isForeignKeyRelationship())) {
return;
}
for (Enumeration fieldsEnum = getForeignKeyFields().elements();
fieldsEnum.hasMoreElements();) {
DatabaseField sourceKey = (DatabaseField)fieldsEnum.nextElement();
databaseRow.add(sourceKey, null);
}
}
/**
* INTERNAL:
* Write fields needed for insert into the template for with null values.
*/
public void writeInsertFieldsIntoRow(AbstractRecord databaseRow, AbstractSession session) {
if (isReadOnly() || (!isForeignKeyRelationship())) {
return;
}
for (Enumeration fieldsEnum = getForeignKeyFields().elements();
fieldsEnum.hasMoreElements();) {
DatabaseField sourceKey = (DatabaseField)fieldsEnum.nextElement();
databaseRow.add(sourceKey, null);
}
}
}