You can write user-defined nodes in C, Java™, or from a subflow.
When you have created a user-defined node, you can test it, as described in Testing a user-defined node. If you want to test or use user-defined nodes or parsers on multiple computers, follow the instructions given in Packaging and distributing user-defined extensions.
The following table shows the tasks that are involved in creating the different types of user-defined node.