Spark实现列转行

Posted 2022-05-26 yszd

一.代码实现　

 1 package big.data.analyse.tokenizer
 2 
 3 import com.hankcs.hanlp.HanLP
 4 import com.hankcs.hanlp.tokenizer.StandardTokenizer
 5 import org.apache.log4j.Level, Logger
 6 import org.apache.spark.sql.SQLContext, Row
 7 import org.apache.spark.sql.catalyst.expressions.StringToMap
 8 import org.apache.spark.sql.types.IntegerType, StringType, StructType, StructField
 9 import org.apache.spark.SparkContext, SparkConf
10 
11 /**
12   * spark中使用Hanlp分词器
13   * Created by zhen on 2019/5/30.
14   */
15 object HanlpTokenizer 
16   /**
17     * 设置日志级别
18     */
19   Logger.getLogger("org").setLevel(Level.WARN)
20   def main(args: Array[String]) 
21     val conf = new SparkConf()
22       .setAppName("HanlpTokenizer")
23       .setMaster("local[2]")
24 
25     val sc = new SparkContext(conf)
26 
27     val sqlContext = new SQLContext(sc)
28     val array : Array[String] = Array("spark-spark发布2.4版本，性能提升巨大，spark生态圈日渐完善",
29       "spark-sparkML机器学习是spark生态圈的重要组成部分，为spark一站式开发注入了强大的活力",
30       "机器学习-随着spark的快速发展，Hadoop的速度难以望其项背，特别是在机器学习和图计算方面，差距更少巨大",
31       "solr-搜索引擎老而弥坚，随着solrcloud的持续发展，在数据量不是特别巨大的情形下，还是具有很多先天优势的",
32       "solr-ES是对solr冲击最为严重的一种技术")
33 
34     val termRdd = sc.parallelize(array).map(row =>  // 标准分词，挂载Hanlp分词器
35       var result = ""
36       val type_content = row.split("-")
37       val termList = StandardTokenizer.segment(type_content(1))
38       for(i <- 0 until termList.size())
39         val term = termList.get(i)
40         //if(!term.nature.name.contains("w") && !term.nature.name().contains("u") && term.nature.name().contains("m"))
41           if(term.word.length > 1)
42             result += term.word + " "
43           
44         //
45       
46       Row(type_content(0),result)
47     )
48 
49    val structType = StructType(Array(
50      StructField("arth_type", StringType, true),
51     StructField("content", StringType, true)
52    ))
53 
54     val termDF = sqlContext.createDataFrame(termRdd,structType)
55 
56     /**
57       * 列转行
58       */
59     val termCheckDF = termDF.rdd.flatMap(row =>
60       val arth_type = row.getAs[String]("arth_type")
61       val content = row.getAs[String]("content")
62       var res = Seq[Row]()
63       val content_array = content.split(" ")
64       for(con <- content_array)
65         res = res :+ Row(arth_type,con, 1)
66       
67       res
68     ).collect()
69 
70     /**
71       * 重新转成df
72       */
73     val structType2 = StructType(Array(
74       StructField("arth_type", StringType, true),
75       StructField("content", StringType, true),
76       StructField("num", IntegerType, true)
77     ))
78 
79     val termListDF = sqlContext.createDataFrame(sc.parallelize(termCheckDF), structType2)
80 
81     /**
82       * 注册临时视图
83       */
84     termListDF.createOrReplaceTempView("termListDF")
85 
86     /**
87       * 分组求和
88       */
89     val result = sqlContext.sql("select arth_type,content,sum(num) num " +
90       "from termListDF group by arth_type,content order by num desc")
91 
92     result.count()
93     result.show(5)
94 
95     sc.stop()
96   
97 

二.结果