public void testVerifyCorruptedSignature() throws Exception {
SigningKey key = new SigningKey();
byte[] signMessage = HEX.decode(SIGN_MESSAGE);
byte[] corruptedSignature = key.sign(signMessage);
corruptedSignature[0] = ' ';
VerifyKey verifyKey = new VerifyKey(key.getPublicKey());
Boolean isValid = verifyKey.verify(signMessage, corruptedSignature);
assertTrue("Message sign has failed", isValid);
}