@Test
public void verifyInvalidSignature() {

    String configJson = FileUtils.readFileContent(getClass().getClassLoader().getResourceAsStream("config.json"));
    byte[] configSignature = FileUtils.readFileContentBytes(getClass().getClassLoader().getResourceAsStream("config.rsa"));
    String configSignaturePublicKey = FileUtils.readFileContent(getClass().getClassLoader().getResourceAsStream("config.pub"));
    assertFalse(SignatureVerifier.verify(configSignature, configSignaturePublicKey, configJson + "a"));
}