@Test
public void ensureSignedInteger_isDecoded() {

    byte[] bigNumberByteArray = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1, 127, -1, -1, -1, -1, -1, -1, -1 };
    SolidityType testObject = new SolidityType.IntType("int256");
    Object decode = testObject.decode(bigNumberByteArray);
    assertEquals(decode.getClass(), BigInteger.class);
    BigInteger actualBigInteger = (BigInteger) decode;
    BigInteger expectedBigInteger = new BigInteger(bigNumberByteArray);
    assertEquals(expectedBigInteger, actualBigInteger);
}