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| 1 | +package sql; |
| 2 | + |
| 3 | +import org.apache.spark.sql.Encoder; |
| 4 | +import org.apache.spark.sql.Encoders; |
| 5 | +import org.apache.spark.sql.SparkSession; |
| 6 | +import org.apache.spark.sql.expressions.Aggregator; |
| 7 | +import org.apache.spark.sql.functions; |
| 8 | +import scala.Serializable; |
| 9 | + |
| 10 | +import java.util.HashMap; |
| 11 | +import java.util.Map; |
| 12 | + |
| 13 | +public class UdafMulti { |
| 14 | + |
| 15 | + public static void main(String[] args) { |
| 16 | + SparkSession spark = SparkSession |
| 17 | + .builder() |
| 18 | + .appName("test") |
| 19 | + .master("local") |
| 20 | + .getOrCreate(); |
| 21 | + // 需先通过sql.Write生成数据 |
| 22 | + spark.read().json("output").createOrReplaceTempView("order"); |
| 23 | + spark.udf().register("userBuy", functions.udaf(new UserBuy(), Encoders.bean(Order.class))); |
| 24 | + spark.sql("select goodId, userBuy(id, userId, goodId, count) as userBuy from order group by goodId").show(); |
| 25 | + spark.close(); |
| 26 | + } |
| 27 | + |
| 28 | + public static class UdafBuffer implements Serializable { |
| 29 | + private Map<Long, Long> map = new HashMap<>(); |
| 30 | + |
| 31 | + public Map<Long, Long> getMap() { |
| 32 | + return map; |
| 33 | + } |
| 34 | + |
| 35 | + public void setMap(Map<Long, Long> map) { |
| 36 | + this.map = map; |
| 37 | + } |
| 38 | + } |
| 39 | + |
| 40 | + public static class UserBuy extends Aggregator<Order, UdafBuffer, String> { |
| 41 | + |
| 42 | + @Override |
| 43 | + public UdafBuffer zero() { |
| 44 | + return new UdafBuffer(); |
| 45 | + } |
| 46 | + |
| 47 | + @Override |
| 48 | + public UdafBuffer reduce(UdafBuffer b, Order a) { |
| 49 | + b.map.compute(a.getUserId(), (user, count) -> { |
| 50 | + if (count == null) { |
| 51 | + return Long.valueOf(a.getCount()); |
| 52 | + } else { |
| 53 | + return count + a.getCount(); |
| 54 | + } |
| 55 | + }); |
| 56 | + return b; |
| 57 | + } |
| 58 | + |
| 59 | + @Override |
| 60 | + public UdafBuffer merge(UdafBuffer b1, UdafBuffer b2) { |
| 61 | + UdafBuffer res = new UdafBuffer(); |
| 62 | + b1.map.forEach((k, v) -> res.map.compute(k, (user, count) -> { |
| 63 | + if (count == null) { |
| 64 | + return Long.valueOf(v); |
| 65 | + } else { |
| 66 | + return count + v; |
| 67 | + } |
| 68 | + })); |
| 69 | + b2.map.forEach((k, v) -> res.map.compute(k, (user, count) -> { |
| 70 | + if (count == null) { |
| 71 | + return Long.valueOf(v); |
| 72 | + } else { |
| 73 | + return count + v; |
| 74 | + } |
| 75 | + })); |
| 76 | + return res; |
| 77 | + } |
| 78 | + |
| 79 | + @Override |
| 80 | + public String finish(UdafBuffer reduction) { |
| 81 | + return reduction.map.toString(); |
| 82 | + } |
| 83 | + |
| 84 | + @Override |
| 85 | + public Encoder<UdafBuffer> bufferEncoder() { |
| 86 | + return Encoders.bean(UdafBuffer.class); |
| 87 | + } |
| 88 | + |
| 89 | + @Override |
| 90 | + public Encoder<String> outputEncoder() { |
| 91 | + return Encoders.STRING(); |
| 92 | + } |
| 93 | + |
| 94 | + } |
| 95 | + |
| 96 | +} |
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