| /* |
| * 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.flink.test.example.java; |
| |
| import org.apache.flink.api.common.functions.FlatMapFunction; |
| import org.apache.flink.api.common.functions.MapFunction; |
| import org.apache.flink.api.common.functions.ReduceFunction; |
| import org.apache.flink.api.java.DataSet; |
| import org.apache.flink.api.java.ExecutionEnvironment; |
| import org.apache.flink.test.testdata.WordCountData; |
| import org.apache.flink.test.util.JavaProgramTestBase; |
| import org.apache.flink.util.Collector; |
| |
| import java.io.Serializable; |
| |
| /** WordCount with subclass and interface example. */ |
| @SuppressWarnings("serial") |
| public class WordCountSubclassInterfacePOJOITCase extends JavaProgramTestBase |
| implements Serializable { |
| private static final long serialVersionUID = 1L; |
| protected String textPath; |
| protected String resultPath; |
| |
| @Override |
| protected void preSubmit() throws Exception { |
| textPath = createTempFile("text.txt", WordCountData.TEXT); |
| resultPath = getTempDirPath("result"); |
| } |
| |
| @Override |
| protected void postSubmit() throws Exception { |
| compareResultsByLinesInMemory(WordCountData.COUNTS, resultPath); |
| } |
| |
| @Override |
| protected void testProgram() throws Exception { |
| final ExecutionEnvironment env = ExecutionEnvironment.getExecutionEnvironment(); |
| DataSet<String> text = env.readTextFile(textPath); |
| |
| DataSet<WCBase> counts = |
| text.flatMap(new Tokenizer()) |
| .groupBy("word") |
| .reduce( |
| new ReduceFunction<WCBase>() { |
| private static final long serialVersionUID = 1L; |
| |
| public WCBase reduce(WCBase value1, WCBase value2) { |
| WC wc1 = (WC) value1; |
| WC wc2 = (WC) value2; |
| int c = |
| wc1.secretCount.getCount() |
| + wc2.secretCount.getCount(); |
| wc1.secretCount.setCount(c); |
| return wc1; |
| } |
| }) |
| .map( |
| new MapFunction<WCBase, WCBase>() { |
| @Override |
| public WCBase map(WCBase value) throws Exception { |
| WC wc = (WC) value; |
| wc.count = wc.secretCount.getCount(); |
| return wc; |
| } |
| }); |
| |
| counts.writeAsText(resultPath); |
| |
| env.execute("WordCount with custom data types example"); |
| } |
| |
| private static final class Tokenizer implements FlatMapFunction<String, WCBase> { |
| |
| @Override |
| public void flatMap(String value, Collector<WCBase> out) { |
| // normalize and split the line |
| String[] tokens = value.toLowerCase().split("\\W+"); |
| // emit the pairs |
| for (String token : tokens) { |
| if (token.length() > 0) { |
| out.collect(new WC(token, 1)); |
| } |
| } |
| } |
| } |
| |
| /** Abstract POJO. */ |
| public abstract static class WCBase { |
| public String word; |
| public int count; |
| |
| public WCBase(String w, int c) { |
| this.word = w; |
| this.count = c; |
| } |
| |
| @Override |
| public String toString() { |
| return word + " " + count; |
| } |
| } |
| |
| /** POJO interface. */ |
| public interface CrazyCounter { |
| int getCount(); |
| |
| void setCount(int c); |
| } |
| |
| /** Implementation of POJO interface. */ |
| public static class CrazyCounterImpl implements CrazyCounter { |
| public int countz; |
| |
| public CrazyCounterImpl() {} |
| |
| public CrazyCounterImpl(int c) { |
| this.countz = c; |
| } |
| |
| @Override |
| public int getCount() { |
| return countz; |
| } |
| |
| @Override |
| public void setCount(int c) { |
| this.countz = c; |
| } |
| } |
| |
| /** Subclass of abstract POJO. */ |
| public static class WC extends WCBase { |
| public CrazyCounter secretCount; |
| |
| public WC() { |
| super(null, 0); |
| } |
| |
| public WC(String w, int c) { |
| super(w, 0); |
| this.secretCount = new CrazyCounterImpl(c); |
| } |
| } |
| } |