A class used to signify the occurrence of a syntax error in a
regular expression that is being compiled. The class is not
declared final so that it may be subclassed for identifying
more specific pattern comilation errors. However, at this point
in time, this package does not subclass MalformedPatternException
for any purpose. This does not preclude users and third party
implementors of the interfaces of this package from subclassing it
for their own purposes.