# Simple Java Regular Expression Parser and Recognizer

This applet lets you enter a simple regular expression and tells you if strings match that regular expression.
Currently, the regular expression language supports
contatenation (ab),
intesection (a+b),
and repeat zero or more times (a*).
'?' matches any symbol.
'^' is the NULL symbol.
Parenthesis are recommended.
Spaces are treated like symbols.
Source code is provided.
Sample regular expressions:

- a
- ((ab)+(a*))
- (a*)
- (This is a test)+(This is not a test)
- ((?*((h+H)ello+(g+G)oodbye)?*)+^)
- ((?*)ab(?*))+^

Source Code

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