Right-Padding a String with Talend Open Studio

Right-Padding a String with Talend Open Studio

This Talend Open Studio example pads a string with 0s if it is shorter than the specified amount.

To pad a String in Talend Open Studio, use the StringUtils.rightPad, leftPad, center, or repeat functions.  This example uses rightPad to add 0s to the end of a String if it's shorter than 8 characters

AAAAADDD -> AAAAADDD
CCCC -> CCCC0000
BBBB0000 -> BBBB00000

The following job sets up a list in a tForeach component of the test input data.  A tIterateToFlow component applies a Commons Lang StringUtils.rightPad function.  The result is output to a tLogRow.  The results of the run and call to the StringUtils function are below.

Application of rightPad() in a tIterateToFlow

Library Call

Commons Lang is a widely-used JAR available in Talend Open Studio. Several versions are installed with Talend 5.  I use 2.6.  The following shows the Basic Settings configuration for tLibraryLoad.

Adding Commons Lang 2.6 to a Project

tLibraryLoad also holds the Java import statements used by the job.  I like to use a Java language feature called static imports which can shorten the Java expressions used in the job (tMap, etc.).  The static import imports a function (or group of functions) rather than a class.  Here's the Advanced Settings tab I used in this job.

tForEach

I test Java expressions on a range of values from a tForEach rather than creating input files or records.  Here is the configuration used for the tForeach.

Input for Job in tForeach

If you need to pad a string or manipulate a string in such a way that it's making your Talend job difficult to maintain, consider using StringUtils from Commons Lang which provides a set of functions to dramatically shorten expression.  Also consider making the hardcoded '8' and '0' context variables: CODE_LENGTH, CODE_PAD_CHAR.