@Test
public void isMultiSigScript() {

    byte[] scriptBytes = Numeric.hexStringToByteArray(""
            + OpCode.PUSH2.toString() // signing threshold
            + OpCode.PUSHDATA1.toString() + "21"// PUSHDATA1 and 33 bytes of key
            + "02028a99826edc0c97d18e22b6932373d908d323aa7f92656a77ec26e8861699ef" // key
            + OpCode.PUSHDATA1.toString() + "21"// PUSHDATA1 and 33 bytes of key
            + "031d8e1630ce640966967bc6d95223d21f44304133003140c3b52004dc981349c9" // key
            + OpCode.PUSHDATA1.toString() + "21"// PUSHDATA1 and 33 bytes of key
            + "03f0f9b358dfed564e74ffe242713f8bc866414226649f59859b140a130818898b" // key
            + OpCode.PUSH3.toString() // number of public keys
            + OpCode.PUSHNULL.toString() // null message
            + OpCode.SYSCALL.toString()
            + InteropServiceCode.NEO_CRYPTO_CHECKMULTISIGWITHECDSASECP256R1.getHash());
    VerificationScript s = new VerificationScript(scriptBytes);
    assertTrue(s.isMultiSigScript());
}