tools/org.eclipse.persistence.tools.db/src/org/eclipse/persistence/tools/db/relational/spi/ExternalForeignKeyColumnPair.java

/*******************************************************************************
 * Copyright (c) 1998, 2012 Oracle. 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
******************************************************************************/
package org.eclipse.persistence.tools.db.relational.spi;

/**
 * Interface describing the meta-data describing a database foreign key.
 * <p>
 * Provisional API: This interface is part of an interim API that is still under development and
 * expected to change significantly before reaching stability. It is available at this early stage
 * to solicit feedback from pioneering adopters on the understanding that any code that uses this
 * API will almost certainly be broken (repeatedly) as the API evolves.<p>
 *
 * @see ExternalForeignKey
 * @version 2.6
 */
public interface ExternalForeignKeyColumnPair {

	/**
	 * Returns the "source" half of the column pair. This is the column on the source table that must
	 * contain a value that matches the value in the target column.
	 */
	ExternalColumn getSourceColumn();

	/**
	 * Returns the "target" half of the column pair. This is typically a column that is part of the
	 * target table's primary key.
	 */
	ExternalColumn getTargetColumn();
}