package com.fei.simple_project;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;

import org.apache.spark.HashPartitioner;
import org.apache.spark.Partitioner;
import org.apache.spark.SparkConf;
import org.apache.spark.api.java.JavaPairRDD;
import org.apache.spark.api.java.JavaRDD;
import org.apache.spark.api.java.JavaSparkContext;
import org.apache.spark.api.java.function.Function;
import org.apache.spark.api.java.function.PairFunction;
import org.apache.spark.api.java.function.VoidFunction;
import org.apache.spark.storage.StorageLevel;

import com.google.common.base.Optional;

import scala.Tuple2;

/**
 * Hello world!
 *
 */
public class App {
	public static void main(String[] args) {
		SparkConf conf = new SparkConf().setAppName("Simple Application");
		JavaSparkContext sc = new JavaSparkContext(conf);

		// convert from other RDD
		JavaRDD<String> line1 = sc.parallelize(Arrays.asList("1 aa", "2 bb", "4 cc", "3 dd"));
		JavaPairRDD<String, String> prdd = line1.mapToPair(new PairFunction<String, String, String>() {
			public Tuple2<String, String> call(String x) throws Exception {
				return new Tuple2(x.split(" ")[0], x);
			}
		});
		System.out.println("111111111111mapToPair:");
		prdd.foreach(new VoidFunction<Tuple2<String, String>>() {
			public void call(Tuple2<String, String> x) throws Exception {
				System.out.println(x);
			}
		});

		// parallelizePairs
		Tuple2 t1 = new Tuple2(1, 2);
		Tuple2 t2 = new Tuple2(3, 4);
		Tuple2 t3 = new Tuple2(3, 6);
		List list1 = new ArrayList<Tuple2>();
		list1.add(t1);
		list1.add(t2);
		list1.add(t3);
		JavaPairRDD<Integer, Integer> line2 = sc.parallelizePairs(list1);
		line2.persist(StorageLevel.MEMORY_ONLY());

		Tuple2 t4 = new Tuple2(3, 9);
		List list2 = new ArrayList<Tuple2>();
		list2.add(t4);
		JavaPairRDD<Integer, Integer> line3 = sc.parallelizePairs(list2);
		line3.persist(StorageLevel.MEMORY_ONLY());
		
		// countByKey
		System.out.println("222222222222222countByKey:");
		Map<Integer, Object> ma = line2.countByKey();
		for(Entry<Integer, Object> e:ma.entrySet()){
			System.out.println(e.getKey()+" "+e.getValue()+" ");
		}
		
		// collectAsMap,如果key已存在，後面覆蓋前面
		System.out.println("3333333333333collectAsMap:");
		Map<Integer, Integer> ca = line2.collectAsMap();
		for(Entry<Integer, Integer> e:ca.entrySet()){
			System.out.println(e.getKey()+" "+e.getValue()+" ");
		}
		
		// lookup
		System.out.println("4444444444444lookup:");
		List<Integer> la = line2.lookup(3);
		for(Integer i:la){
			System.out.println(i+" ");
		}
		
		// partitionBy,  partitioner, join+filter
		Tuple2 ta = new Tuple2(1,"sina");
		Tuple2 tb = new Tuple2(2, "taobao");
		Tuple2 td = new Tuple2(2, "126");
		List lista = new ArrayList<Tuple2>();
		lista.add(ta);
		lista.add(tb);
		lista.add(td);
		//自帶hash分割槽，此外還有range分割槽
		JavaPairRDD<Integer, String> linea = sc.parallelizePairs(lista).partitionBy(new HashPartitioner(2));
		linea.persist(StorageLevel.MEMORY_ONLY());
		Optional<Partitioner> op = linea.partitioner();
		System.out.println("5555555555partitioner: "+ op);
		System.out.println("66666666666present: "+ op.isPresent());
		if (op.isPresent()) {
			System.out.println("77777777value:"+ op.get().numPartitions());
		}
		
		Tuple2 tc = new Tuple2(2, "126");
		Tuple2 te = new Tuple2(2, "baidu");
		Tuple2 tf = new Tuple2(1, "dangdang");
		List listc = new ArrayList<Tuple2>();
		listc.add(tc);
		listc.add(te);
		listc.add(tf);
		//自定義分割槽
		JavaPairRDD<Integer, String> linec = sc.parallelizePairs(listc).partitionBy(new MyPartitioner(2));
		linec.persist(StorageLevel.MEMORY_ONLY());
		System.out.println("888888888888partitioner: "+ linec.partitioner());
		
		System.out.println("9999999999join:");
		JavaPairRDD<Integer, Tuple2<String, String>> js = linea.join(linec);
		js.foreach(new VoidFunction<Tuple2<Integer, Tuple2<String,String>>>(){
			public void call(Tuple2<Integer, Tuple2<String, String>> x) throws Exception {
				System.out.println(x);
			}
		});
		JavaPairRDD<Integer, Tuple2<String, String>> fs = js.filter(new Function<Tuple2<Integer, Tuple2<String, String>>, Boolean>(){
			public Boolean call(Tuple2<Integer, Tuple2<String, String>> y) throws Exception {
				return !y._2._1.equals(y._2._2);
			}
		});
		System.out.println("aaaaaaaaaaafilter:");
		fs.foreach(new VoidFunction<Tuple2<Integer, Tuple2<String,String>>>(){
			public void call(Tuple2<Integer, Tuple2<String, String>> x) throws Exception {
				System.out.println(x);
			}
		});
	}
}
 

package com.fei.simple_project;

import org.apache.spark.Partitioner;

public class MyPartitioner extends Partitioner {
	public int num;
	public MyPartitioner(int N) {
		num = N;
	}
	@Override
	public int getPartition(Object x) {
		int ret = x.hashCode()%num;
		if(ret<0)
			ret=(-1)*ret;
		return ret;
	}
	@Override
	public int numPartitions() {
		return num;
	}
}
 

111111111111mapToPair:
[Stage 0:>                                                          (0 + 0) / 4]16/02/04 20:15:45 WARN SizeEstimator: Failed to check whether UseCompressedOops is set; assuming yes
(2,2 bb)
(4,4 cc)
(3,3 dd)
(1,1 aa)
222222222222222countByKey:                                                      
1 1 
3 2 
3333333333333collectAsMap:
1 2 
3 6 
4444444444444lookup:
4 
6 
5555555555partitioner: Optional.of(
 
[email protected])
66666666666present: true
77777777value:2
888888888888partitioner: Optional.of([email protected])
9999999999join:
(1,(sina,dangdang))
(2,(taobao,126))
(2,(taobao,baidu))
(2,(126,126))
(2,(126,baidu))
aaaaaaaaaaafilter:
(1,(sina,dangdang))
(2,(taobao,126))
(2,(taobao,baidu))
(2,(126,baidu))