Coboldoc is a java web 2.0 style interface for analyzing COBOL. It maintains its own cross reference database for static & dynamic calls to help with impact analysis or for general COBOL surfing. It's also designed to run directly on z/OS
PL1DOC is a documentation tool for PL1 projects entirely written in Java. It currently supports PL1 version 2.3 (later releases will be captured in the future). PL1DOC produces HTML output and provides a tagset to allow a rich annotation of source files.