void readInvalid(String input, Class<? extends Exception> exceptionClass, String exceptiondMessage) throws IOException {
expectedException.expect(exceptionClass);
expectedException.expectMessage(exceptiondMessage);
StreamSourceDelegate source =
new StreamSourceDelegate(new JsonStreamSourceImpl(new Yylex(new StringReader(input)), true));
try {
source.copy(new JsonStreamTargetImpl(new StringWriter(), true));
} finally {
source.close();
}
}