decimal operators builder

DecimalOperators.java

    public static final ParametricFunction DECIMAL_ADD_OPERATOR = decimalAddOperator();

    private static ParametricFunction decimalAddOperator()
    {
        Signature signature = Signature.builder()
                .type(SCALAR)
                .operatorType(ADD)
                .argumentTypes("decimal(p, s)", "decimal(p, s)")
                .returnType("decimal(min(38, p + 1), s)")
                .build();
        return ParametricFunction.builder(DecimalOperators.class)
                .signature(signature)
                .methods("addShortShortShort", "addLongLongLong", "addShortShortLong")
                .build();
    }

    public static long addShortShortShort(long a, long b)
    {
        return a + b;
    }

    public static Slice addShortShortLong(long a, long b)
    {
        BigInteger aBigInteger = BigInteger.valueOf(a);
        BigInteger bBigInteger = BigInteger.valueOf(b);
        BigInteger result = aBigInteger.add(bBigInteger);
        return LongDecimalType.unscaledValueToSlice(result);
    }

    public static Slice addLongLongLong(Slice a, Slice b)
    {
        BigInteger aBigInteger = LongDecimalType.unscaledValueToBigInteger(a);
        BigInteger bBigInteger = LongDecimalType.unscaledValueToBigInteger(b);
        BigInteger result = aBigInteger.add(bBigInteger);
        checkOverflow(result);
        return LongDecimalType.unscaledValueToSlice(result);
    }