> 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/examples.md).

# Examples

The `data-integration/samples/transformations` directory contains the following example KTRs that show how to use this step:

| Example KTR File                                                   | Description                                                                  |
| ------------------------------------------------------------------ | ---------------------------------------------------------------------------- |
| `User Defined Java Class - Calculate the date of Easter.ktr`       | Develops a class to calculate the date of Easter.                            |
| `User Defined Java Class - Concatenate firstname and lastname.ktr` | Develops a class to combine first and last names into a full name.           |
| `User Defined Java Class - Query the database catalog.ktr`         | Shows how a user-defined class would access a database.                      |
| `User Defined Java Class - Real-time search on Twitter.ktr`        | Shows how to use a user-defined class in a real-time system.                 |
| `User Defined Java Class - LambdaExamples.ktr`                     | Shows how to use the Java streaming API with a User Defined Java Class step. |

We recommend starting with the `User Defined Java Class - Calculate the date of Easter.ktr` example transformation.


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