@Test(expected = IllegalArgumentException.class)
public void testHash256ParamCreationFromTooShortString() {

    String sig = "576f6f6c6f576f6f6c6f576f6f6c6f576f6f6c6ff6c6f576f6f6c6f576f6f6c";
    ContractParameter.hash256(sig);
}