transform-function-java.md

The TransformFunction API provides the following methods for extension by subclasses:

public void setup(ServerInterface srvInterface, SizedColumnTypes argTypes);

public abstract void processPartition(ServerInterface srvInterface,
        PartitionReader input_reader, PartitionWriter input_writer)
    throws UdfException, DestroyInvocation;

protected void cancel(ServerInterface srvInterface);

public void destroy(ServerInterface srvInterface, SizedColumnTypes argTypes);

The PartitionReader and PartitionWriter classes provide getters and setters for column values, along with next() to iterate through partitions. See the API reference documentation for details.