小编Sam*_*jee的帖子

我有一个简单的spark应用程序，试图在YARN Cluster上广播String类型的变量。但是每次我尝试访问广播的变量值时，在Task中都会得到null。如果你们可以提出建议，这对我在这里做错的事情真的很有帮助。我的代码如下：

public class TestApp implements Serializable { 
  static Broadcast<String[]> mongoConnectionString; 

  public static void main( String[] args ) { 
    String mongoBaseURL = args[0]; 
    SparkConf sparkConf =  new SparkConf().setAppName(Constants.appName); 
    JavaSparkContext javaSparkContext = new JavaSparkContext(sparkConf); 

    mongoConnectionString = javaSparkContext.broadcast(args); 

    JavaSQLContext javaSQLContext = new JavaSQLContext(javaSparkContext); 

    JavaSchemaRDD javaSchemaRDD = javaSQLContext.jsonFile(hdfsBaseURL+Constants.hdfsInputDirectoryPath); 

    if(javaSchemaRDD!=null) { 
      javaSchemaRDD.registerTempTable("LogAction"); 
      javaSchemaRDD.cache(); 
      pageSchemaRDD = javaSQLContext.sql(SqlConstants.getLogActionPage); 
      pageSchemaRDD.foreach(new Test());     
    } 
  } 

  private static class Test implements VoidFunction<Row> { 
    private static final long serialVersionUID = 1L; 

    public void call(Row t) throws Exception { 
      logger.info("mongoConnectionString "+mongoConnectionString.value()); 
    } …