Tutorial5.java

/*
 * Copyright (c) 2008-2013, Hazelcast, Inc. All Rights Reserved.
 *
 * Licensed 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 tutorials;

import com.hazelcast.core.HazelcastInstance;
import com.hazelcast.core.ICompletableFuture;
import com.hazelcast.core.IList;
import com.hazelcast.mapreduce.Job;
import com.hazelcast.mapreduce.JobTracker;
import com.hazelcast.mapreduce.KeyValueSource;
import model.Crime;
import model.CrimeCategory;
import model.Person;
import tutorials.impl.CrimeMapper;
import tutorials.impl.CrimeReducerFactory;
import tutorials.impl.SalaryCollator;
import tutorials.impl.SalaryCombinerFactory;
import tutorials.impl.SalaryMapper;
import tutorials.impl.SalaryReducerFactory;
import tutorials.impl.ToStringPrettyfier;

import java.util.List;
import java.util.Map;

public class Tutorial5
        implements Tutorial {

    @Override
    public void execute(HazelcastInstance hazelcastInstance)
            throws Exception {

        JobTracker jobTracker = hazelcastInstance.getJobTracker("default");

        IList<Person> list = hazelcastInstance.getList("persons");
        KeyValueSource<String, Person> source = KeyValueSource.fromList(list);

        Job<String, Person> job = jobTracker.newJob(source);

        ICompletableFuture<List<Map.Entry<String, Integer>>> future =
                job.mapper(new SalaryMapper())
                        .combiner(new SalaryCombinerFactory())
                        .reducer(new SalaryReducerFactory())
                        .submit(new SalaryCollator());

        // Intermediate result
        List<Map.Entry<String, Integer>> orderedSalariesByState = future.get();
        Map.Entry<String, Integer> topSalary = orderedSalariesByState.get(0);

        IList<Crime> crimesList = hazelcastInstance.getList("crimes");
        KeyValueSource<String, Crime> crimeSource = KeyValueSource.fromList(crimesList);

        Job<String, Crime> crimeJob = jobTracker.newJob(crimeSource);

        ICompletableFuture<Map<CrimeCategory, Integer>> crimeFuture =
                crimeJob.mapper(new CrimeMapper(topSalary.getKey()))
                        .reducer(new CrimeReducerFactory())
                        .submit();

        System.out.println(ToStringPrettyfier.toString(crimeFuture.get()));
    }
}