OpenGrok is a fast and usable source code search and cross reference engine. It helps you search, cross-reference and navigate your source tree. It can understand various program file formats and version control histories like Mercurial, Git, SCCS, RCS, CVS, Subversion, Teamware, ClearCase, Perforce
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and Bazaar. In other words it lets you grok (profoundly understand) the open source, hence the name OpenGrok. It is written in Java. [Less]