1 /* 2 * Licensed to the Apache Software Foundation (ASF) under one 3 * or more contributor license agreements. See the NOTICE file 4 * distributed with this work for additional information 5 * regarding copyright ownership. The ASF licenses this file 6 * to you under the Apache License, Version 2.0 (the 7 * "License"); you may not use this file except in compliance 8 * with the License. You may obtain a copy of the License at 9 * 10 * http://www.apache.org/licenses/LICENSE-2.0 11 * 12 * Unless required by applicable law or agreed to in writing, software 13 * distributed under the License is distributed on an "AS IS" BASIS, 14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 15 * See the License for the specific language governing permissions and 16 * limitations under the License. 17 */ 18 package org.apache.giraph.block_app.framework.piece; 19 20 import org.apache.giraph.block_app.framework.api.BlockWorkerApi; 21 import org.apache.giraph.block_app.framework.api.BlockWorkerValueAccessor; 22 import org.apache.hadoop.io.Writable; 23 import org.apache.hadoop.io.WritableComparable; 24 25 /** 26 * Piece that should be extended when WorkerContext is used. 27 * 28 * @param <I> Vertex id type 29 * @param <V> Vertex value type 30 * @param <E> Edge value type 31 * @param <M> Message type 32 * @param <WV> Worker value type 33 * @param <WM> Worker message type 34 * @param <S> Execution stage type 35 */ 36 @SuppressWarnings("rawtypes") 37 public class PieceWithWorkerContext<I extends WritableComparable, 38 V extends Writable, E extends Writable, M extends Writable, WV, 39 WM extends Writable, S> 40 extends DefaultParentPiece<I, V, E, M, WV, WM, S> { 41 42 /** 43 * Get global worker value. 44 * Value returned can be accessed from may threads, and so all 45 * accesses to it should be done in a thread-safe manner! 46 * 47 * This is the only place in Blocks Framework where you need 48 * to take care of concurrency. 49 */ 50 @SuppressWarnings("unchecked") 51 public WV getWorkerValue(BlockWorkerApi<I> workerApi) { 52 return (WV) ((BlockWorkerValueAccessor) workerApi).getWorkerValue(); 53 } 54 }