/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package org.apache.openjpa.persistence.jdbc.mapping.bidi;
import java.util.Collection;
import java.util.HashSet;
import java.util.Set;
import javax.persistence.CascadeType;
import javax.persistence.Entity;
import javax.persistence.FetchType;
import javax.persistence.Id;
import javax.persistence.OneToMany;
import org.apache.openjpa.persistence.jdbc.ElementJoinColumn;
/**
* Parent in a logically bidirectional but actually unidirectional parent-child
* relationship where Child holds reference to Parent via primary key and not
* via object reference.
* Parent identity is assigned by the application. Hence, Parent sets the
* children's reference to Parent whenever its identity is set by the
* application or a new child is added.
*
* @author Pinaki Poddar
*
*/
@Entity
public class ParentWithAppIdentity implements IParent {
@Id
private long id;
private String name;
/**
* This field is <em>not</em> mapped by the child. The child's table will
* hold an <em>implicit</em> foreign key linking to the primary key of this
* Parent's table.
*/
@OneToMany(cascade = CascadeType.ALL, fetch=FetchType.LAZY)
@ElementJoinColumn(name="FK_PARENT_APP_ID", referencedAttributeName="id")
private Set<Child> children;
public long getId() {
return id;
}
public void setId(long id) {
this.id = id;
postIdSet();
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Collection<Child> getChildren() {
return children;
}
public void addChild(Child child) {
if (children == null)
children = new HashSet<Child>();
children.add(child);
child.setAppParentId(this.id);
}
public boolean removeChild(Child child) {
return children != null && children.remove(child);
}
/**
* This method will be called when application has assigned identity
* to this instance.
*/
public void postIdSet() {
if (children == null)
return;
for (Child child : children) {
child.setAppParentId(this.getId());
}
}
}