spork-master/src/org/apache/pig/builtin/Nondeterministic.java
/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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 org.apache.pig.builtin;

import java.lang.annotation.Documented;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;

import org.apache.pig.classification.InterfaceAudience;
import org.apache.pig.classification.InterfaceStability;

/**
 * <p>A non-deterministic UDF is one that can produce different results when
 * invoked on the same input. Examples of non-deterministic behavior might be,
 * for example, getCurrentTime() or random().</p>
 * <p>Certain Pig optimizations depend on UDFs being deterministic. It is therefore
 * very important for correctness that non-deterministic UDFs be annotated as such.</p>
 */
@InterfaceAudience.Public
@InterfaceStability.Unstable
@Documented
@Retention(value=RetentionPolicy.RUNTIME)
public @interface Nondeterministic {

}
