/**
* sample采样倾斜key单独进行join
*/
JavaPairRDD<Long, String> sampledRDD = userid2PartAggrInfoRDD.sample(false, 0.1, 9);
JavaPairRDD<Long, Long> mappedSampledRDD = sampledRDD.mapToPair(
new PairFunction<Tuple2<Long,String>, Long, Long>() {
private static final long serialVersionUID = 1L;
@Override
public Tuple2<Long, Long> call(Tuple2<Long, String> tuple)
throws Exception {
return new Tuple2<Long, Long>(tuple._1, 1L);
}
});
JavaPairRDD<Long, Long> computedSampledRDD = mappedSampledRDD.reduceByKey(
new Function2<Long, Long, Long>() {
private static final long serialVersionUID = 1L;
@Override
public Long call(Long v1, Long v2) throws Exception {
return v1 + v2;
}
});
JavaPairRDD<Long, Long> reversedSampledRDD = computedSampledRDD.mapToPair(
new PairFunction<Tuple2<Long,Long>, Long, Long>() {
private static final long serialVersionUID = 1L;
@Override
public Tuple2<Long, Long> call(Tuple2<Long, Long> tuple)
throws Exception {
return new Tuple2<Long, Long>(tuple._2, tuple._1);
}
});
final Long skewedUserid = reversedSampledRDD.sortByKey(false).take(1).get(0)._2;
JavaPairRDD<Long, String> skewedRDD = userid2PartAggrInfoRDD.filter(
new Function<Tuple2<Long,String>, Boolean>() {
private static final long serialVersionUID = 1L;
@Override
public Boolean call(Tuple2<Long, String> tuple) throws Exception {
return tuple._1.equals(skewedUserid);
}
});
JavaPairRDD<Long, String> commonRDD = userid2PartAggrInfoRDD.filter(
new Function<Tuple2<Long,String>, Boolean>() {
private static final long serialVersionUID = 1L;
@Override
public Boolean call(Tuple2<Long, String> tuple) throws Exception {
return !tuple._1.equals(skewedUserid);
}
});
JavaPairRDD<String, Row> skewedUserid2infoRDD = userid2InfoRDD.filter(
new Function<Tuple2<Long,Row>, Boolean>() {
private static final long serialVersionUID = 1L;
@Override
public Boolean call(Tuple2<Long, Row> tuple) throws Exception {
return tuple._1.equals(skewedUserid);
}
}).flatMapToPair(new PairFlatMapFunction<Tuple2<Long,Row>, String, Row>() {
private static final long serialVersionUID = 1L;
@Override
public Iterable<Tuple2<String, Row>> call(
Tuple2<Long, Row> tuple) throws Exception {
Random random = new Random();
List<Tuple2<String, Row>> list = new ArrayList<Tuple2<String, Row>>();
for(int i = 0; i < 100; i++) {
int prefix = random.nextInt(100);
list.add(new Tuple2<String, Row>(prefix + "_" + tuple._1, tuple._2));
}
return list;
}
});
JavaPairRDD<Long, Tuple2<String, Row>> joinedRDD1 = skewedRDD.mapToPair(
new PairFunction<Tuple2<Long,String>, String, String>() {
private static final long serialVersionUID = 1L;
@Override
public Tuple2<String, String> call(Tuple2<Long, String> tuple)
throws Exception {
Random random = new Random();
int prefix = random.nextInt(100);
return new Tuple2<String, String>(prefix + "_" + tuple._1, tuple._2);
}
}).join(skewedUserid2infoRDD).mapToPair(
new PairFunction<Tuple2<String,Tuple2<String,Row>>, Long, Tuple2<String, Row>>() {
private static final long serialVersionUID = 1L;
@Override
public Tuple2<Long, Tuple2<String, Row>> call(
Tuple2<String, Tuple2<String, Row>> tuple)
throws Exception {
long userid = Long.valueOf(tuple._1.split("_")[1]);
return new Tuple2<Long, Tuple2<String, Row>>(userid, tuple._2);
}
});
JavaPairRDD<Long, Tuple2<String, Row>> joinedRDD2 = commonRDD.join(userid2InfoRDD);
JavaPairRDD<Long, Tuple2<String, Row>> joinedRDD = joinedRDD1.union(joinedRDD2);
JavaPairRDD<String, String> sessionid2FullAggrInfoRDD = joinedRDD.mapToPair(
new PairFunction<Tuple2<Long,Tuple2<String,Row>>, String, String>() {
private static final long serialVersionUID = 1L;
@Override
public Tuple2<String, String> call(
Tuple2<Long, Tuple2<String, Row>> tuple)
throws Exception {
String partAggrInfo = tuple._2._1;
Row userInfoRow = tuple._2._2;
String sessionid = StringUtils.getFieldFromConcatString(
partAggrInfo, "\\|", Constants.FIELD_SESSION_ID);
int age = userInfoRow.getInt(3);
String professional = userInfoRow.getString(4);
String city = userInfoRow.getString(5);
String sex = userInfoRow.getString(6);
String fullAggrInfo = partAggrInfo + "|"
+ Constants.FIELD_AGE + "=" + age + "|"
+ Constants.FIELD_PROFESSIONAL + "=" + professional + "|"
+ Constants.FIELD_CITY + "=" + city + "|"
+ Constants.FIELD_SEX + "=" + sex;
return new Tuple2<String, String>(sessionid, fullAggrInfo);
}
});
