/*******************************************************************************
* Copyright (c) 1998, 2008 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
******************************************************************************/
package org.eclipse.persistence.oxm.mappings;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.StringTokenizer;
import java.util.Vector;
import javax.xml.namespace.QName;
import org.eclipse.persistence.descriptors.ClassDescriptor;
import org.eclipse.persistence.exceptions.DatabaseException;
import org.eclipse.persistence.exceptions.DescriptorException;
import org.eclipse.persistence.internal.descriptors.ObjectBuilder;
import org.eclipse.persistence.internal.helper.NonSynchronizedVector;
import org.eclipse.persistence.internal.oxm.Reference;
import org.eclipse.persistence.internal.oxm.ReferenceResolver;
import org.eclipse.persistence.internal.oxm.XMLConversionManager;
import org.eclipse.persistence.internal.queries.CollectionContainerPolicy;
import org.eclipse.persistence.internal.queries.ContainerPolicy;
import org.eclipse.persistence.internal.queries.JoinedAttributeManager;
import org.eclipse.persistence.internal.queries.MapContainerPolicy;
import org.eclipse.persistence.internal.sessions.AbstractRecord;
import org.eclipse.persistence.internal.sessions.AbstractSession;
import org.eclipse.persistence.mappings.ContainerMapping;
import org.eclipse.persistence.oxm.XMLField;
import org.eclipse.persistence.oxm.record.UnmarshalRecord;
import org.eclipse.persistence.oxm.record.XMLRecord;
import org.eclipse.persistence.queries.ObjectBuildingQuery;
/**
* TopLink OXM version of a 1-M mapping. A list of source-target key field
* associations is used to link the source xpaths to their related target
* xpaths, and hence their primary key (unique identifier) values used when
* (un)marshalling.
*
* It is important to note that each target xpath is assumed to be set as a primary
* key field on the target (reference) class descriptor - this is necessary in order
* to locate the correct target object instance in the session cache when resolving
* mapping references.
*
* The usesSingleNode flag should be set to true if the keys are to be written out in space-separated
* lists.
*
* @see XMLObjectReferenceMapping
* @see ContainerMapping
*/
public class XMLCollectionReferenceMapping extends XMLObjectReferenceMapping implements ContainerMapping {
protected ContainerPolicy containerPolicy; // type of container used to hold the aggregate objects
private static final String SPACE = " ";
private boolean usesSingleNode;
/**
* PUBLIC:
* The default constructor initializes the sourceToTargetKeyFieldAssociations
* and sourceToTargetKeys data structures.
*/
public XMLCollectionReferenceMapping() {
sourceToTargetKeyFieldAssociations = new HashMap();
sourceToTargetKeys = new NonSynchronizedVector();
this.containerPolicy = ContainerPolicy.buildDefaultPolicy();
this.usesSingleNode = false;
}
/**
* INTERNAL:
* Retrieve the target object's primary key value that is mapped to a given
* source xpath (in the source-target key field association list).
*
* @param targetObject - the reference class instance that holds the required pk value
* @param xmlFld
* @param session
* @return null if the target object is null, the reference class is null, or
* a primary key field name does not exist on the reference descriptor that
* matches the target field name - otherwise, return the associated primary
* key value
*/
public Object buildFieldValue(Object targetObject, XMLField xmlFld, AbstractSession session) {
if (targetObject == null || getReferenceClass() == null) {
return null;
}
ClassDescriptor descriptor = getReferenceDescriptor();
ObjectBuilder objectBuilder = descriptor.getObjectBuilder();
Vector pks = objectBuilder.extractPrimaryKeyFromObject(targetObject, session);
XMLField tgtXMLField = (XMLField) getSourceToTargetKeyFieldAssociations().get(xmlFld);
int idx = descriptor.getPrimaryKeyFields().indexOf(tgtXMLField);
if (idx == -1) {
return null;
}
return pks.get(idx);
}
/**
* INTERNAL:
* Create (if necessary) and populate a reference object that will be used
* during the mapping reference resolution phase after unmarshalling is
* complete.
*
* @param record
* @param xmlField
* @param object
* @param session
* @return
*/
public void buildReference(UnmarshalRecord record, XMLField xmlField, Object object, AbstractSession session) {
ReferenceResolver resolver = ReferenceResolver.getInstance(session);
if (resolver == null) {
return;
}
Object srcObject = record.getCurrentObject();
Reference reference = resolver.getReference(this, srcObject);
// if reference is null, create a new instance and set it on the resolver
if (reference == null) {
reference = new Reference(this, srcObject, getReferenceClass(), new HashMap());
resolver.addReference(reference);
}
XMLField tgtFld = (XMLField) getSourceToTargetKeyFieldAssociations().get(xmlField);
String tgtXPath = tgtFld.getXPath();
Vector pks;
HashMap primaryKeyMap = reference.getPrimaryKeyMap();
if (primaryKeyMap.containsKey(tgtXPath)) {
pks = (Vector) primaryKeyMap.get(tgtXPath);
} else {
pks = new Vector();
primaryKeyMap.put(tgtXPath, pks);
}
ClassDescriptor descriptor = session.getClassDescriptor(getReferenceClass());
Class type = descriptor.getTypedField(tgtFld).getType();
XMLConversionManager xmlConversionManager = (XMLConversionManager) session.getDatasourcePlatform().getConversionManager();
for (StringTokenizer stok = new StringTokenizer((String) object); stok.hasMoreTokens();) {
Object value = xmlConversionManager.convertObject(stok.nextToken(), type);
if (value != null) {
pks.add(value);
}
}
}
/**
* INTERNAL:
* Return the mapping's containerPolicy.
*/
public ContainerPolicy getContainerPolicy() {
return containerPolicy;
}
/**
* INTERNAL:
* The mapping is initialized with the given session. This mapping is fully initialized
* after this.
*/
public void initialize(AbstractSession session) throws DescriptorException {
super.initialize(session);
ContainerPolicy cp = getContainerPolicy();
if (cp != null) {
if (cp.getContainerClass() == null) {
Class cls = session.getDatasourcePlatform().getConversionManager().convertClassNameToClass(cp.getContainerClassName());
cp.setContainerClass(cls);
}
}
}
/**
* INTERNAL:
* Extract the primary key values from the row, then create an
* org.eclipse.persistence.internal.oxm.Reference instance and stored it
* on the session's org.eclipse.persistence.internal.oxm.ReferenceResolver.
*/
public Object readFromRowIntoObject(AbstractRecord databaseRow, JoinedAttributeManager joinManager, Object targetObject, ObjectBuildingQuery sourceQuery, AbstractSession executionSession) throws DatabaseException {
ClassDescriptor descriptor = sourceQuery.getSession().getClassDescriptor(getReferenceClass());
ContainerPolicy cp = this.getContainerPolicy();
Vector pkFieldNames = referenceDescriptor.getPrimaryKeyFieldNames();
Vector primaryKeyValues = new Vector();
primaryKeyValues.setSize(pkFieldNames.size());
HashMap primaryKeyMap = new HashMap();
// for each source xmlField, get the value from the row and store
for (Iterator fieldIt = getFields().iterator(); fieldIt.hasNext();) {
XMLField fld = (XMLField) fieldIt.next();
XMLField tgtFld = (XMLField) getSourceToTargetKeyFieldAssociations().get(fld);
Object fieldValue = databaseRow.getValues(fld);
if ((fieldValue == null) || (fieldValue instanceof String) || !(fieldValue instanceof Vector)) {
return cp.containerInstance();
}
// fix for bug# 5687430
// need to get the actual type of the target (i.e. int, String, etc.)
// and use the converted value when checking the cache.
XMLConversionManager xmlConversionManager = (XMLConversionManager) executionSession.getDatasourcePlatform().getConversionManager();
Vector newValues = new Vector();
for (Iterator valIt = ((Vector) fieldValue).iterator(); valIt.hasNext();) {
for (StringTokenizer stok = new StringTokenizer((String) valIt.next()); stok.hasMoreTokens();) {
Object value = xmlConversionManager.convertObject(stok.nextToken(), descriptor.getTypedField(tgtFld).getType());
if (value != null) {
newValues.add(value);
}
}
}
primaryKeyMap.put(tgtFld.getXPath(), newValues);
}
// store the Reference instance on the resolver for use during mapping resolution phase
ReferenceResolver resolver = ReferenceResolver.getInstance(sourceQuery.getSession());
if (resolver != null) {
resolver.addReference(new Reference(this, targetObject, referenceClass, primaryKeyMap));
}
return null;
}
/**
* ADVANCED:
* Set the mapping's containerPolicy.
*/
public void setContainerPolicy(ContainerPolicy containerPolicy) {
// set reference class here if necessary
this.containerPolicy = containerPolicy;
if (this.containerPolicy instanceof MapContainerPolicy) {
((MapContainerPolicy) this.containerPolicy).setElementClass(getReferenceClass());
}
}
/**
* PUBLIC:
* Configure the mapping to use an instance of the specified container class
* to hold the target objects.
* <p>jdk1.2.x: The container class must implement (directly or indirectly) the Collection interface.
* <p>jdk1.1.x: The container class must be a subclass of Vector.
*/
public void useCollectionClass(Class concreteContainerClass) {
this.setContainerPolicy(ContainerPolicy.buildPolicyFor(concreteContainerClass));
}
public void useCollectionClassName(String concreteContainerClassName) {
this.setContainerPolicy(new CollectionContainerPolicy(concreteContainerClassName));
}
/**
* PUBLIC:
* Configure the mapping to use an instance of the specified container class
* to hold the target objects. The key used to index the value in the Map
* is the value returned by a call to the specified zero-argument method.
* The method must be implemented by the class (or a superclass) of the
* value to be inserted into the Map.
* <p>jdk1.2.x: The container class must implement (directly or indirectly) the Map interface.
* <p>jdk1.1.x: The container class must be a subclass of Hashtable.
* <p>The referenceClass must be set before calling this method.
*/
public void useMapClass(Class concreteContainerClass, String methodName) {
// the reference class has to be specified before coming here
if (this.getReferenceClass() == null) {
throw DescriptorException.referenceClassNotSpecified(this);
}
ContainerPolicy policy = ContainerPolicy.buildPolicyFor(concreteContainerClass);
policy.setKeyName(methodName, getReferenceClass().getName());
this.setContainerPolicy(policy);
}
/**
* INTERNAL:
* For the purpose of XMLCollectionReferenceMappings, 'usesSingleNode'
* refers to the fact that the source key xpath fields should all be written as
* space-separated lists. Would be used for mapping to an IDREFS field in a schema
*/
public boolean usesSingleNode() {
return this.usesSingleNode;
}
public void setUsesSingleNode(boolean useSingleNode) {
this.usesSingleNode = useSingleNode;
}
/**
* INTERNAL:
* Write the attribute value from the object to the row.
*/
public void writeFromObjectIntoRow(Object object, AbstractRecord row, AbstractSession session) {
// for each xmlField on this mapping
for (Iterator fieldIt = getFields().iterator(); fieldIt.hasNext();) {
XMLField xmlField = (XMLField) fieldIt.next();
ContainerPolicy cp = getContainerPolicy();
Object collection = getAttributeAccessor().getAttributeValueFromObject(object);
if (collection == null) {
return;
}
Object fieldValue;
Object objectValue;
String stringValue = "";
QName schemaType;
Object iterator = cp.iteratorFor(collection);
if (usesSingleNode()) {
while (cp.hasNext(iterator)) {
objectValue = cp.next(iterator, session);
fieldValue = buildFieldValue(objectValue, xmlField, session);
if (fieldValue != null) {
schemaType = getSchemaType(xmlField, fieldValue, session);
String newValue = getValueToWrite(schemaType, fieldValue, session);
if (newValue != null) {
stringValue += newValue;
if (cp.hasNext(iterator)) {
stringValue += SPACE;
}
}
}
}
if (!(stringValue.equals(""))) {
row.put(xmlField, stringValue);
}
} else {
ArrayList keyValues = new ArrayList();
while (cp.hasNext(iterator)) {
objectValue = cp.next(iterator, session);
fieldValue = buildFieldValue(objectValue, xmlField, session);
if (fieldValue != null) {
schemaType = getSchemaType(xmlField, fieldValue, session);
stringValue = getValueToWrite(schemaType, fieldValue, session);
//row.add(xmlField, stringValue);
keyValues.add(stringValue);
}
}
row.put(xmlField, keyValues);
}
}
}
public void writeSingleValue(Object value, Object parent, XMLRecord row, AbstractSession session) {
for (Iterator fieldIt = getFields().iterator(); fieldIt.hasNext();) {
XMLField xmlField = (XMLField) fieldIt.next();
Object fieldValue = buildFieldValue(value, xmlField, session);
if (fieldValue != null) {
QName schemaType = getSchemaType(xmlField, fieldValue, session);
String stringValue = getValueToWrite(schemaType, fieldValue, session);
row.add(xmlField, stringValue);
}
}
}
}