> For the complete documentation index, see [llms.txt](https://docs.pentaho.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.pentaho.com/pdia-data-integration/10.2-data-integration/pdi-transformation-steps-reference-overview/user-defined-java-class/options-user-defined-java-class/parameters-tab.md).

# Parameters tab

![Parameters tab](https://2745965000-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FvZoINBz5C5WnDZQlbOJQ%2Fuploads%2Fgit-blob-a8a7a4e34e2f7d0b6d3c738158b50702dc6a1d4b%2FPDITransStep_UserDefinedJavaClass_ParametersTab.png?alt=media)

You can use the **Parameters** table to avoid using hard-coded string values, such as field names (customer for example).

Another example is in the `User Defined Java Class - Calculate the date of Easter.ktr` sample transformation, which is in the `data-integration/samples/transformations` directory. That sample KTR has a parameter called **YEAR**. The **YEAR** parameter is referenced with the `getParameter()method`, as shown in the following example:

```
getParameter("YEAR")
```

At runtime, it will return the year String value.

## Class Member Variables and the getVariable Function

When getting parameters that point to transformation parameters, the User Defined Java Class step behaves differently depending on when the `getVariable` function is called. If it is in the `init()` method, the parameters behave as expected. If the initialization is on a class member variable, the variable is not resolved by design, as shown in the following example:

```java
private final String par = getVariable("somePar"); // DOES NOT resolve correctly
private String par2 = null;
 
public boolean processRow(StepMetaInterface smi, StepDataInterface sdi) throws KettleException {
   logBasic("Parameter value="+par+"\[MEMBER INIT\]");
   logBasic("Parameter value="+par2+"\[INIT FUNCTION\]");
   setOutputDone();
   return false;
}
 
public boolean init(StepMetaInterface stepMetaInterface, StepDataInterface stepDataInterface) {
   par2 = getVariable("somePar"); // WORKS FINE
   return parent.initImpl(stepMetaInterface, stepDataInterface);
}
```


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation by asking a question.

Perform an HTTP GET request on the following URL with the `ask` and `goal` query parameters:

```
GET https://docs.pentaho.com/pdia-data-integration/10.2-data-integration/pdi-transformation-steps-reference-overview/user-defined-java-class/options-user-defined-java-class/parameters-tab.md?ask=<question>&goal=<user_goal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is what the user is ultimately trying to achieve, the reason they need the answer. Sharing it helps GitBook give you a better, more relevant answer. A goal is most helpful when it describes the outcome the user wants rather than restating the question. For example, with `ask=how do I create an API token`, a goal like `automate deployments from our CI pipeline` lets GitBook tailor the answer to that use case.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.