> 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/9.3-data-integration/pdi-transformation-steps-reference-overview/user-defined-java-class/options-user-defined-java-class/parameters-tab.md).

# Parameters tab

![Parameters tab](/files/WUHsyBRSCjkgKeC8BfA3)

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);
}
```


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