openjpa-jdbc/src/main/java/org/apache/openjpa/jdbc/meta/strats/SuperclassDiscriminatorStrategy.java

/*
 * 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.jdbc.meta.strats;

import java.sql.SQLException;

import org.apache.openjpa.jdbc.kernel.JDBCStore;
import org.apache.openjpa.jdbc.meta.ClassMapping;
import org.apache.openjpa.jdbc.sql.Joins;
import org.apache.openjpa.jdbc.sql.Result;
import org.apache.openjpa.jdbc.sql.SQLBuffer;
import org.apache.openjpa.jdbc.sql.Select;

/**
 * Discriminator strategy that delegates to superclass discriminator.
 *
 * @author Abe White
 */
public class SuperclassDiscriminatorStrategy
    extends AbstractDiscriminatorStrategy {

    
    private static final long serialVersionUID = 1L;

    @Override
    public void map(boolean adapt) {
        // if a superclass maps the discriminator value, so should we.
        // otherwise assume it's calculated
        ClassMapping sup = disc.getClassMapping().
            getJoinablePCSuperclassMapping();
        for (; sup != null; sup = sup.getJoinablePCSuperclassMapping()) {
            if (sup.getDiscriminator().getValue() != null
                || sup.getDiscriminator().getStrategy() instanceof
                ValueMapDiscriminatorStrategy) {
                disc.setValue(disc.getMappingInfo().getValue(disc, adapt));
                break;
            }
        }
    }

    @Override
    public void loadSubclasses(JDBCStore store)
        throws SQLException, ClassNotFoundException {
        disc.getClassMapping().getPCSuperclassMapping().
            getDiscriminator().loadSubclasses(store);
        disc.setSubclassesLoaded(true);
    }

    @Override
    public Class getClass(JDBCStore store, ClassMapping base, Result res)
        throws SQLException, ClassNotFoundException {
        return disc.getClassMapping().getPCSuperclassMapping().
            getDiscriminator().getClass(store, base, res);
    }

    @Override
    public boolean hasClassConditions(ClassMapping base, boolean subclasses) {
        return disc.getClassMapping().getPCSuperclassMapping().
            getDiscriminator().hasClassConditions(base, subclasses);
    }

    @Override
    public SQLBuffer getClassConditions(Select sel, Joins joins,
        ClassMapping base, boolean subclasses) {
        return disc.getClassMapping().getPCSuperclassMapping().
            getDiscriminator().getClassConditions(sel, joins, base, subclasses);
    }
}