/*******************************************************************************
* Copyright (c) 2011, 2013 Oracle and/or its affiliates. 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:
* bdoughan - initial implementation
* tware - initial unmarshall method
******************************************************************************/
package org.eclipse.persistence.jpa.rs.util.xmladapters;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import javax.xml.bind.annotation.adapters.XmlAdapter;
import org.eclipse.persistence.config.CacheUsage;
import org.eclipse.persistence.config.QueryHints;
import org.eclipse.persistence.descriptors.ClassDescriptor;
import org.eclipse.persistence.internal.dynamic.DynamicEntityImpl;
import org.eclipse.persistence.jpa.rs.PersistenceContext;
import org.eclipse.persistence.jpa.rs.util.IdHelper;
import org.eclipse.persistence.mappings.DatabaseMapping;
import org.eclipse.persistence.queries.FetchGroup;
/**
* Used with JAXB to convert from a URL representing an relationship to an object
* It provides functionality at marshall and unmarshall time
*
* At marshall time, the target of a relationship will be marshalled as a URL that could be
* used to find the object through a REST service
*
* At unmarsall time, the URL will be deconstructed and used to find the object in JPA.
*
* @author tware
*
*/
public class LinkAdapter extends XmlAdapter<String, Object> {
private String baseURI = null;
protected PersistenceContext context;
public LinkAdapter() {
}
public LinkAdapter(String baseURI, PersistenceContext context) {
this.baseURI = baseURI;
this.context = context;
}
@Override
public Object unmarshal(String v) throws Exception {
if (v.equals("")){
return null;
}
String fixedString = v.replace("\\/", "/");
int lastSlash = fixedString.lastIndexOf('/');
String entityType = fixedString.substring((baseURI + context.getName() + "/entity/" ).length(), lastSlash);
String entityId = fixedString.substring(lastSlash + 1);
ClassDescriptor descriptor = context.getDescriptor(entityType);
Object id = IdHelper.buildId(context, descriptor.getAlias(), entityId);
return constructObjectForId(entityType, id);
}
protected Object constructObjectForId(String entityType, Object id){
FetchGroup fetchGroup = new FetchGroup();
ClassDescriptor descriptor = context.getDescriptor(entityType);
List<DatabaseMapping> pkMappings = descriptor.getObjectBuilder().getPrimaryKeyMappings();
for (DatabaseMapping mapping: pkMappings){
fetchGroup.addAttribute(mapping.getAttributeName());
}
Map<String, Object> properties = new HashMap<String, Object>();
properties.put(QueryHints.FETCH_GROUP, fetchGroup);
properties.put(QueryHints.CACHE_USAGE, CacheUsage.CheckCacheOnly);
Object entity = context.find(null, entityType, id, properties);
if (entity == null){
return IdHelper.buildObjectShell(context, entityType, id);
}
return entity;
}
@Override
public String marshal(Object v) throws Exception {
if (null == v) {
return null;
}
String href = null;
String version = context.getVersion();
if (version != null) {
href = baseURI + version + "/" + context.getName() + "/entity/" + v.getClass().getSimpleName() + "/"
+ IdHelper.stringifyId((DynamicEntityImpl) v, ((DynamicEntityImpl) v).getType().getName(), context);
} else {
href = baseURI + context.getName() + "/entity/" + v.getClass().getSimpleName() + "/"
+ IdHelper.stringifyId((DynamicEntityImpl) v, ((DynamicEntityImpl) v).getType().getName(), context);
}
return href;
}
}