Jflex

JFlex is a lexical analyzer generator (also known as scanner generator). It is also a rewrite of the very useful tool JLex which was developed by Elliot Berk at Princeton University. JFlex is designed to work together with the LALR parser generator CUP by Scott Hudson, and the Java modification of Berkeley Yacc BYacc/J by Bob Jamison. It can also be used together with other parser generators like ANTLR or as a standalone tool.