java - 将两个存在于 hive 中的 spark 表连接起来

Question

我已经在 eclipse 中编写了 Java 程序来连接 spark 中的两个表，但是在 package 附近出现错误 这是下面的错误

The type scala.reflect.api.TypeTags$TypeTag cannot be resolved. It is indirectly referenced from required .class files

这是我写的程序

package joins;

import org.apache.spark.SparkConf;
import org.apache.spark.SparkContext;
import org.apache.spark.api.java.JavaSparkContext;
import org.apache.spark.sql.DataFrame;
import org.apache.spark.sql.hive.HiveContext;

public class Spark {
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        SparkConf conf = new SparkConf();
        SparkContext sc = new SparkContext(conf);
        HiveContext sqlContext = new org.apache.spark.sql.hive.HiveContext(sc);
        sqlContext.sql(" use myown ");
        DataFrame table_01 = sqlContext.sql("SELECT * FROM customer");
        table_01.saveAsTable("spark_table_01");
        sqlContext.cacheTable("spark_table_01");
        DataFrame table_02 = sqlContext.sql("SELECT * FROM account");
        table_02.saveAsTable("spark_table_02");
        sqlContext.cacheTable("spark_table_02");
        DataFrame table_join = sqlContext.sql(" SELECT a.* FROM  customer a join account b on a.ssn=b.ssn ");
        table_join.insertInto("customeraccount");
        sqlContext.uncacheTable("spark_table_01");
        sqlContext.uncacheTable("spark_table_02");
    }
}

Answer 1

您的应用程序中似乎缺少 scala reflect jar 文件。下载scala-reflect.jar，放入类路径中，重新编译。