Java developers can use the BIRT APIs to create a custom report designer or a custom report generator.

A custom report designer is a Java application that a Java developer creates to generate a well-formed report design file based on specific requirements. A custom report designer does not necessarily include a user interface. A typical example of a custom report designer is a Java application that dynamically determines the content, structure, or data source for a report, based on business logic. A custom report designer uses the same design engine API as BIRT Report Designer.

A custom Java report generator performs the same function as the BIRT report generator and is typically integrated into either a web application or a stand‑alone Java application. A custom Java report generator uses the Report Engine API to read a report design file and generate a report. A custom Java report generator can use business logic to implement security requirements, control content, and determine the output format.