The Java transformation provides a simple native programming interface to define transformation functionality with the Java programming language. You can use the Java transformation to define simple or moderately complex transformation functionality without advanced knowledge of the Java programming language or an external Java development environment. The Java transformation is an active or passive transformation.

The Developer tool uses the Java Development Kit (JDK) to compile the Java code and generate byte code for the transformation. The Developer tool stores the byte code in the Model repository.

The Data Integration Service uses the Java Runtime Environment (JRE) to run generated byte code at run time. When the Data Integration Service runs a mapping with a Java transformation, the Data Integration Service uses the JRE to run the byte code and process input rows and generate output rows.

Create Java transformations by writing Java code snippets that define transformation logic. Define transformation behavior for a Java transformation based on the following events:

In mappings that run on the Spark engine, you can use complex data types in Java transformations to process hierarchical data. With complex data types, the Spark engine directly reads, processes, and writes hierarchical data in Avro, Parquet, and JSON complex files.