Transformation Guide

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Defining Helper Code

On the

Helper Code

Helpers

tab, you can declare user-defined variables and methods for the Java transformation class in active or passive Java transformations.

After you declare variables and methods on the

Helper Code

Helpers

tab, you can use the variables and methods on any code entry tab except the

Import Packages

Imports

tab.

On the

Helper Code

Helpers

tab, you can declare the following types of code, variables, and methods:

Static code and static variables.

Within a static block, you can declare static variables and static code. All instances of a reusable Java transformation in a mapping

and all partitions in a session

share static code and variables. Static code runs before any other code in a Java transformation.

For example, the following code declares a static variable to store the error threshold for all instances of a Java transformation in a mapping:

static int errorThreshold;

Use this variable to store the error threshold for the transformation and access it from all instances of the Java transformation in a mapping

and from any partition in a session

You must synchronize static variables

in a multiple partition session or

in a reusable Java transformation.

Instance variables.

You can declare partition-level instance variables.

Multiple instances of a reusable Java transformation in a mapping

or multiple partitions in a session

do not share instance variables. Declare instance variables with a prefix to avoid conflicts and initialize non-primitive instance variables.

For example, the following code uses a boolean variable to decide whether to generate an output row:

// boolean to decide whether to generate an output row 
// based on validity of input
private boolean generateRow;

User-defined static or instance methods.

Extends the functionality of the Java transformation. Java methods declared on the

Helper Code

Helpers

tab can use or modify output variables or locally declared instance variables. You cannot access input variables from Java methods on the

Helper Code

Helpers

tab.

For example, use the following code on the

Helpers

tab to declare a function that adds two integers:

private int myTXAdd (int num1,int num2)
{
     return num1+num2;
}

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Table of Contents

Transformation Guide

Transformation Guide

Defining Helper Code

Defining Helper Code