SpringBoot+SparkSQL操作JSON字符串

在SpringBoot中通过maven来做包管理构建，有几个地方需要注意一下的，需要解决包之间的冲突，否则运行时会报错：

（1）sparkSQL中需要先排除两个包：

        <dependency>
            <groupId>org.apache.spark</groupId>
            <artifactId>spark-sql_2.11</artifactId>
            <version>${spark.version}</version>
            <exclusions>
                <exclusion>
                    <groupId>org.codehaus.janino</groupId>
                    <artifactId>janino</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>org.codehaus.janino</groupId>
                    <artifactId>commons-compiler</artifactId>
                </exclusion>
            </exclusions>
        </dependency>

（2）重新引入:

        <dependency>
            <groupId>org.codehaus.janino</groupId>
            <artifactId>commons-compiler</artifactId>
            <version>2.7.8</version>
        </dependency>

        <dependency>
            <groupId>org.codehaus.janino</groupId>
            <artifactId>janino</artifactId>
            <version>2.7.8</version>
        </dependency>

ok,准备工作做完之后，开始代码层面得工作：

主要给大家演示的场景是将json字符串转换成临时表，然后通过sparkSQL操作临时表，非常简单方便：

public class SparkJsonSQL {

    public void Exec(){
        SparkConf conf = new SparkConf();
        conf.setMaster("local[2]").setAppName("jsonRDD");
        JavaSparkContext sc = new JavaSparkContext(conf);
        SQLContext sqlContext = new SQLContext(sc);

        JavaRDD<String> nameRDD = sc.parallelize(Arrays.asList(
                "{\"name\":\"zhangsan\",\"age\":\"18\"}",
                "{\"name\":\"lisi\",\"age\":\"19\"}",
                "{\"name\":\"wangwu\",\"age\":\"20\"}"
        ));
        JavaRDD<String> scoreRDD = sc.parallelize(Arrays.asList(
                "{\"name\":\"zhangsan\",\"score\":\"100\"}",
                "{\"name\":\"lisi\",\"score\":\"200\"}",
                "{\"name\":\"wangwu\",\"score\":\"300\"}"
        ));

        Dataset<Row> namedf = sqlContext.read().json(nameRDD);
        Dataset<Row> scoredf = sqlContext.read().json(scoreRDD);
        namedf.registerTempTable("name");
        scoredf.registerTempTable("score");

        Dataset<Row> result = sqlContext.sql("select name.name,name.age,score.score from name,score where name.name = score.name");
        //Dataset<Row> result = sqlContext.sql("select * from name");
        result.show();
        result.foreach(x ->System.out.print(x));
        sc.stop();
    }
}

我们将程序运行起来看看效果：