| /* |
| * 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.backend.hadoop.executionengine.tez; |
| |
| import java.io.IOException; |
| import java.util.Map; |
| import java.util.Set; |
| |
| import org.apache.commons.logging.Log; |
| import org.apache.commons.logging.LogFactory; |
| import org.apache.hadoop.conf.Configuration; |
| import org.apache.pig.EvalFunc; |
| import org.apache.pig.backend.executionengine.ExecException; |
| import org.apache.pig.data.Tuple; |
| import org.apache.tez.runtime.api.LogicalInput; |
| import org.apache.tez.runtime.library.api.KeyValueReader; |
| |
| public class ReadScalarsTez extends EvalFunc<Object> implements TezInput { |
| private static final Log LOG = LogFactory.getLog(ReadScalarsTez.class); |
| private String inputKey; |
| private transient Tuple t; |
| private transient LogicalInput input; |
| |
| public ReadScalarsTez(String inputKey) { |
| this.inputKey = inputKey; |
| } |
| |
| @Override |
| public String[] getTezInputs() { |
| return new String[] { inputKey }; |
| } |
| |
| @Override |
| public void replaceInput(String oldInputKey, String newInputKey) { |
| if (oldInputKey.equals(inputKey)) { |
| inputKey = newInputKey; |
| } |
| } |
| |
| @Override |
| public void addInputsToSkip(Set<String> inputsToSkip) { |
| String cacheKey = "scalar-" + inputKey; |
| Object cacheValue = ObjectCache.getInstance().retrieve(cacheKey); |
| if (cacheValue != null) { |
| inputsToSkip.add(inputKey); |
| } |
| } |
| |
| @Override |
| public void attachInputs(Map<String, LogicalInput> inputs, |
| Configuration conf) throws ExecException { |
| String cacheKey = "scalar-" + inputKey; |
| Object cacheValue = ObjectCache.getInstance().retrieve(cacheKey); |
| if (cacheValue != null) { |
| t = (Tuple) cacheValue; |
| return; |
| } |
| input = inputs.get(inputKey); |
| if (input == null) { |
| throw new ExecException("Input from vertex " + inputKey + " is missing"); |
| } |
| try { |
| KeyValueReader reader = (KeyValueReader) input.getReader(); |
| if (reader.next()) { |
| t = (Tuple) reader.getCurrentValue(); |
| String first = t == null ? null : t.toString(); |
| if (reader.next()) { |
| String msg = "Scalar has more than one row in the output. " |
| + "1st : " + first + ", 2nd :" |
| + reader.getCurrentValue(); |
| throw new ExecException(msg); |
| } |
| } else { |
| LOG.info("Scalar input from vertex " + inputKey + " is null"); |
| } |
| LOG.info("Attached input from vertex " + inputKey + " : input=" + input + ", reader=" + reader); |
| } catch (Exception e) { |
| throw new ExecException(e); |
| } |
| ObjectCache.getInstance().cache(cacheKey, t); |
| log.info("Cached scalar in Tez ObjectRegistry with vertex scope. cachekey=" + cacheKey); |
| } |
| |
| @Override |
| public Object exec(Tuple input) throws IOException { |
| int pos = (Integer) input.get(0); |
| Object obj = t.get(pos); |
| return obj; |
| } |
| } |