/***********************************************************************************************************************
* Copyright (C) 2010-2013 by the Stratosphere project (http://stratosphere.eu)
*
* Licensed 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 eu.stratosphere.api.common.operators;
/**
* Enumeration representing order. May represent no order, an ascending order or a descending order.
*/
public enum Order {
/**
* Indicates no order.
*/
NONE,
/**
* Indicates an ascending order.
*/
ASCENDING,
/**
* Indicates a descending order.
*/
DESCENDING,
/**
* Indicates an order without a direction. This constant is not used to indicate
* any existing order, but for example to indicate that an order of any direction
* is desirable.
*/
ANY;
// --------------------------------------------------------------------------------------------
/**
* Checks, if this enum constant represents in fact an order. That is,
* whether this property is not equal to <tt>Order.NONE</tt>.
*
* @return True, if this enum constant is unequal to <tt>Order.NONE</tt>,
* false otherwise.
*/
public boolean isOrdered() {
return this != Order.NONE;
}
public String getShortName() {
return this == ASCENDING ? "ASC" : this == DESCENDING ? "DESC" : this == ANY ? "*" : "-";
}
}