Rename a Field
Updated: Jun 29, 2023
This example is designed to rename fields in a dataset, allowing users to modify the names of specific columns or attributes. It provides a convenient and flexible way to customize the field names according to user preferences or standard naming conventions.
Input CSV file
Account,LastName,FirstName,Balance,CreditLimit,AccountCreated,Rating 101,Reeves,Keanu,9315.45,10000.00,1/17/1998,A 312,Butler,Gerard,90.00,1000.00,8/6/2003,B 868,Hewitt,Jennifer Love,0,17000.00,5/25/1985,B 761,Pinkett-Smith,Jada,49654.87,100000.00,12/5/2006,A 317,Murray,Bill,789.65,5000.00,2/5/2007,C
Java Code Listing
package com.northconcepts.datapipeline.examples.cookbook; import java.io.File; import com.northconcepts.datapipeline.core.DataReader; import com.northconcepts.datapipeline.core.StreamWriter; import com.northconcepts.datapipeline.csv.CSVReader; import com.northconcepts.datapipeline.job.Job; import com.northconcepts.datapipeline.transform.RenameField; import com.northconcepts.datapipeline.transform.TransformingReader; public class RenameAField { public static void main(String[] args) throws Throwable { DataReader reader = new CSVReader(new File("example/data/input/credit-balance-01.csv")) .setFieldNamesInFirstRow(true); reader = new TransformingReader(reader) .add(new RenameField("Rating", "Score")); Job.run(reader, new StreamWriter(System.out)); } }
Code walkthrough
- CSVReader is created corresponding to the input file
credit-balance-01.csv
. - The
CSVReader.setFieldNamesInFirstRow(true)
method is invoked to specify that the names specified in the first row should be used as field names. - A TransformingReader is created to apply one or more transformations to the incoming data sequentially.
- RenameField object accepts
oldName
andnewName
String arguments. In the given example, the "Rating" (oldName) field is renamed to "Score" (newName). - Data is transferred from the
reader
to theStreamWriter(System.out)
via Job.run() method.
Output
----------------------------------------------- 0 - Record { 0:[Account]:STRING=[101]:String 1:[LastName]:STRING=[Reeves]:String 2:[FirstName]:STRING=[Keanu]:String 3:[Balance]:STRING=[9315.45]:String 4:[CreditLimit]:STRING=[10000.00]:String 5:[AccountCreated]:STRING=[1/17/1998]:String 6:[Score]:STRING=[A]:String } ----------------------------------------------- 1 - Record { 0:[Account]:STRING=[312]:String 1:[LastName]:STRING=[Butler]:String 2:[FirstName]:STRING=[Gerard]:String 3:[Balance]:STRING=[90.00]:String 4:[CreditLimit]:STRING=[1000.00]:String 5:[AccountCreated]:STRING=[8/6/2003]:String 6:[Score]:STRING=[B]:String } ----------------------------------------------- 2 - Record { 0:[Account]:STRING=[868]:String 1:[LastName]:STRING=[Hewitt]:String 2:[FirstName]:STRING=[Jennifer Love]:String 3:[Balance]:STRING=[0]:String 4:[CreditLimit]:STRING=[17000.00]:String 5:[AccountCreated]:STRING=[5/25/1985]:String 6:[Score]:STRING=[B]:String } ----------------------------------------------- 3 - Record { 0:[Account]:STRING=[761]:String 1:[LastName]:STRING=[Pinkett-Smith]:String 2:[FirstName]:STRING=[Jada]:String 3:[Balance]:STRING=[49654.87]:String 4:[CreditLimit]:STRING=[100000.00]:String 5:[AccountCreated]:STRING=[12/5/2006]:String 6:[Score]:STRING=[A]:String } ----------------------------------------------- 4 - Record { 0:[Account]:STRING=[317]:String 1:[LastName]:STRING=[Murray]:String 2:[FirstName]:STRING=[Bill]:String 3:[Balance]:STRING=[789.65]:String 4:[CreditLimit]:STRING=[5000.00]:String 5:[AccountCreated]:STRING=[2/5/2007]:String 6:[Score]:STRING=[C]:String } ----------------------------------------------- 5 records