src/javax/persistence/criteria/Order.java

/*******************************************************************************
 * Copyright (c) 2008 - 2012 Oracle Corporation. 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:
 *     Linda DeMichiel - Java Persistence 2.1
 *     Linda DeMichiel - Java Persistence 2.0
 *
 ******************************************************************************/
package javax.persistence.criteria;

/**
 * An object that defines an ordering over the query results.
 *
 * @since Java Persistence 2.0
 */
public interface Order {

   /**
    * Switch the ordering.
    * @return a new <code>Order</code> instance with the reversed ordering
    */
    Order reverse();

   /**
    * Whether ascending ordering is in effect.
    * @return boolean indicating whether ordering is ascending
    */
    boolean isAscending();

   /**
    * Return the expression that is used for ordering.
    * @return expression used for ordering
    */
   Expression<?> getExpression();
}