Checkstyle is a development tool to help programmers write Java code that adheres to a coding standard. By default it supports the Sun Code Conventions, but is highly configurable. It can be invoked with an ANT task and a command line program.
Open source project that offer summary and download services on this page is a project that carry out their development work on other open source development sites. Their work is linked to this page via a feature called OFI, and their work is not carried out here on OSDN site.