Retrieve DataFrame Values in a Java Array

Question

I am using apache spark. I want to retrieve the values pf DataFrame in a String type array. I have created a table using DataFrame.

dataframe.registerTempTable("table_name");
DataFrame d2=sqlContext.sql("Select * from table_name");

Now I want this data to be retrieved in a java Array(String type would be fine). How can I do that.

abaghel · Accepted Answer · 2016-10-06 11:45:21Z

4

You can use collect() method to get Row[]. Each Row contains column values of your Dataframe.If there is single value in each row then you can add them in ArrayList of String. If there are more than one column in each row then use ArrayList of your custom object type and set the properties. In below code instead of printing "Row Data" you can add them in ArrayList.

    Row[] dataRows = d2.collect();
    for (Row row : dataRows) {
        System.out.println("Row : "+row);
         for (int i = 0; i < row.length(); i++) {
                System.out.println("Row Data : "+row.get(i));
         }
    }

answered Oct 6, 2016 at 11:45

abaghel

15.4k2 gold badges56 silver badges69 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

Retrieve DataFrame Values in a Java Array

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related