| /* |
| * 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.Inherited; |
| import java.lang.annotation.Retention; |
| import java.lang.annotation.RetentionPolicy; |
| import java.util.concurrent.TimeUnit; |
| |
| import org.apache.pig.backend.hadoop.executionengine.physicalLayer.util.MonitoredUDFExecutor; |
| import org.apache.pig.backend.hadoop.executionengine.physicalLayer.util.MonitoredUDFExecutor.ErrorCallback; |
| import org.apache.pig.classification.InterfaceAudience; |
| import org.apache.pig.classification.InterfaceStability; |
| |
| |
| /** |
| * Describes how the execution of a UDF should be monitored, and what |
| * to do if it times out. |
| * <p> |
| * NOTE: does not work with UDFs that implement the Accumulator interface |
| * <p> |
| * |
| * Setting a default value will cause it to be used instead of null when the UDF times out. |
| * The appropriate value among in, long, string, etc, is used. |
| * The default fields of these annotations are arrays for Java reasons I won't bore you with. |
| * <p> |
| * Set them as if they were primitives: <code>@MonitoredUDF( intDefault=5 )</code> |
| * <p> |
| * There is currently no way to provide a default ByteArray, Tuple, Map, or Bag. Null will always be used for those. |
| * <p> |
| * Currently this annotation is ignored when the Accumulator interface is used. |
| */ |
| @InterfaceAudience.Public |
| @InterfaceStability.Unstable |
| @Documented |
| @Inherited |
| @Retention(value=RetentionPolicy.RUNTIME) |
| public @interface MonitoredUDF { |
| /** |
| * Time Units in which to measure timeout value. |
| * @return Time Units in which to measure timeout value. |
| */ |
| TimeUnit timeUnit() default TimeUnit.SECONDS; |
| |
| /** |
| * Number of time units after which the execution should be halted and default returned. |
| * @return Number of time units after which the execution should be halted and default returned. |
| */ |
| int duration() default 10; |
| |
| int[] intDefault() default {}; |
| long[] longDefault() default {}; |
| double[] doubleDefault() default {}; |
| float[] floatDefault() default {}; |
| String[] stringDefault() default {}; |
| |
| /** |
| * UDF author can implement a static extension of MonitoredUDFExecutor.ErrorCallback and provide its class |
| * to the annotation in order to perform custom error handling. |
| */ |
| Class<? extends ErrorCallback> errorCallback() default MonitoredUDFExecutor.ErrorCallback.class; |
| } |