/*
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
 * 
 * // Copyright (c) 1998, 2007, Oracle. All rights reserved.
 * 
 *
 * The contents of this file are subject to the terms of either the GNU
 * General Public License Version 2 only ("GPL") or the Common Development
 * and Distribution License("CDDL") (collectively, the "License").  You
 * may not use this file except in compliance with the License. You can obtain
 * a copy of the License at https://glassfish.dev.java.net/public/CDDL+GPL.html
 * or glassfish/bootstrap/legal/LICENSE.txt.  See the License for the specific
 * language governing permissions and limitations under the License.
 * 
 * When distributing the software, include this License Header Notice in each
 * file and include the License file at glassfish/bootstrap/legal/LICENSE.txt.
 * Sun designates this particular file as subject to the "Classpath" exception
 * as provided by Sun in the GPL Version 2 section of the License file that
 * accompanied this code.  If applicable, add the following below the License
 * Header, with the fields enclosed by brackets [] replaced by your own
 * identifying information: "Portions Copyrighted [year]
 * [name of copyright owner]"
 * 
 * Contributor(s):
 * 
 * If you wish your version of this file to be governed by only the CDDL or
 * only the GPL Version 2, indicate your decision by adding "[Contributor]
 * elects to include this software in this distribution under the [CDDL or GPL
 * Version 2] license."  If you don't indicate a single choice of license, a
 * recipient has the option to distribute your version of this file under
 * either the CDDL, the GPL Version 2 or to extend the choice of license to
 * its licensees as provided above.  However, if you add GPL Version 2 code
 * and therefore, elected the GPL Version 2 license, then the option applies
 * only if the new code is made subject to such option by the copyright
 * holder.
 */
package oracle.toplink.essentials.querykeys;

import oracle.toplink.essentials.internal.helper.DatabaseField;
import oracle.toplink.essentials.descriptors.ClassDescriptor;

/**
 * <p>
 * <b>Purpose</b>: Define an alias to a database field.
 * <p>
 * <b>Responsibilities</b>:
 * <ul>
 * <li> Define the field that is being aliased.
 * </ul>
 */
public class DirectQueryKey extends QueryKey {
    DatabaseField field;

    /**
     * INTERNAL:
     * Return the field for the query key.
     */
    public DatabaseField getField() {
        return field;
    }

    /**
     * PUBLIC:
     * Return the field name for the query key.
     */
    public String getFieldName() {
        return getField().getName();
    }

    /**
     * PUBLIC:
     * Return the qualified field name for the query key.
     */
    public String getQualifiedFieldName() {
        return getField().getQualifiedName();
    }

    /**
     * INTERNAL:
     * Initialize any information in the receiver that requires its descriptor.
     * Set the receiver's descriptor back reference.
     * @param descriptor is the owner descriptor of the receiver.
     */
    public void initialize(ClassDescriptor descriptor) {
        super.initialize(descriptor);
        if (!getField().hasTableName()) {
            getField().setTable(descriptor.getDefaultTable());
        }
    }

    /**
     * INTERNAL:
     * override the isDirectQueryKey() method in the superclass to return true.
     * @return boolean
     */
    public boolean isDirectQueryKey() {
        return true;
    }

    /**
     * INTERNAL:
     * Set the field for the query key.
     */
    public void setField(DatabaseField field) {
        this.field = field;
    }

    /**
     * PUBLIC:
     * Set the field name for the query key.
     */
    public void setFieldName(String fieldName) {
        setField(new DatabaseField(fieldName));
    }
}