UniqueConstraintMetadata.java

/*******************************************************************************
 * Copyright (c) 1998, 2015 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:
 *     Oracle - initial API and implementation from Oracle TopLink
 *     05/16/2008-1.0M8 Guy Pelletier
 *       - 218084: Implement metadata merging functionality between mapping file
 *     11/06/2009-2.0 Guy Pelletier
 *       - 286317: UniqueConstraint xml element is changing (plus couple other fixes, see bug)
 *     03/24/2011-2.3 Guy Pelletier
 *       - 337323: Multi-tenant with shared schema support (part 1)
 *     11/19/2012-2.5 Guy Pelletier
 *       - 389090: JPA 2.1 DDL Generation Support (foreign key metadata support)
 *******************************************************************************/
package org.eclipse.persistence.internal.jpa.metadata.tables;

import java.util.ArrayList;
import java.util.List;

import org.eclipse.persistence.internal.jpa.metadata.ORMetadata;
import org.eclipse.persistence.internal.jpa.metadata.accessors.MetadataAccessor;
import org.eclipse.persistence.internal.jpa.metadata.accessors.objects.MetadataAnnotation;

/**
 * INTERNAL:
 * Object to hold onto a unique constraint metadata.
 *
 * Key notes:
 * - any metadata mapped from XML to this class must be compared in the
 *   equals method.
 * - when loading from annotations, the constructor accepts the metadata
 *   accessor this metadata was loaded from. Used it to look up any
 *   'companion' annotation needed for processing.
 * - methods should be preserved in alphabetical order.
 *
 */
public class UniqueConstraintMetadata extends ORMetadata {
    private String m_name;
    private List<String> m_columnNames;

    /**
     * INTERNAL:
     * Used for XML loading.
     */
    public UniqueConstraintMetadata() {
        super("<unique-constraint>");
    }

    /**
     * INTERNAL:
     * Used for annotation loading.
     */
    public UniqueConstraintMetadata(MetadataAnnotation uniqueConstraint, MetadataAccessor accessor) {
        super(uniqueConstraint, accessor);

        m_name = uniqueConstraint.getAttributeString("name");

        m_columnNames = new ArrayList<String>();

        for (Object columnName : uniqueConstraint.getAttributeArray("columnNames")) {
            m_columnNames.add((String) columnName);
        }
    }

    /**
     * INTERNAL:
     */
    @Override
    public boolean equals(Object objectToCompare) {
        if (objectToCompare instanceof UniqueConstraintMetadata) {
            UniqueConstraintMetadata uniqueConstraint = (UniqueConstraintMetadata) objectToCompare;

            if (! valuesMatch(m_name, uniqueConstraint.getName())) {
                return false;
            }

            return valuesMatch(m_columnNames, uniqueConstraint.getColumnNames());
        }

        return false;
    }

    @Override
    public int hashCode() {
        int result = m_name != null ? m_name.hashCode() : 0;
        result = 31 * result + (m_columnNames != null ? m_columnNames.hashCode() : 0);
        return result;
    }

    /**
     * INTERNAL:
     * Used for OX mapping.
     */
    public List<String> getColumnNames() {
        return m_columnNames;
    }

    /**
     * INTERNAL:
     * Used for OX mapping.
     */
    public String getName() {
        return m_name;
    }

    /**
     * INTERNAL:
     * Return true if a name has been specified for this unique constraint.
     */
    public boolean hasName() {
        return m_name != null && !m_name.equals("");
    }

    /**
     * INTERNAL:
     * Used for OX mapping.
     */
    public void setColumnNames(List<String> columnNames) {
        m_columnNames = columnNames;
    }

    /**
     * INTERNAL:
     * Used for OX mapping.
     */
    public void setName(String name) {
        m_name = name;
    }
}