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static final int safeAdd(int left, int right)
                 throws ArithmeticException {
  if (right > 0 ? left > Integer.MAX_VALUE - right
                : left < Integer.MIN_VALUE - right) {
    throw new ArithmeticException("Integer overflow");
  }
  return left + right;
}

static final int safeSubtract(int left, int right) 
                 throws ArithmeticException {
  if (right > 0 ? left < Integer.MIN_VALUE + right 
                : left > Integer.MAX_VALUE + right) {
    throw new ArithmeticException("Integer overflow");
  }
  return left - right;
}

static final int safeMultiply(int left, int right)
                 throws ArithmeticException {
  if (right > 0 ? left > Integer.MAX_VALUE/right
                  || left < Integer.MIN_VALUE/right 
                : (right < -1 ? left > Integer.MIN_VALUE/right 
                                || left < Integer.MAX_VALUE/right
                              : right == -1 
                                && left == Integer.MIN_VALUE) ) {
    throw new ArithmeticException("Integer overflow");
  }
  return left * right;
}

static final int safeDivide(int left, int right)
                 throws ArithmeticException {
  if ((left == Integer.MIN_VALUE) && (right == -1)) {
    throw new ArithmeticException("Integer overflow");
  }
  return left / right;
}

static final int safeNegate(int a) throws ArithmeticException {
  if (a == Integer.MIN_VALUE) {
    throw new ArithmeticException("Integer overflow");
  }
  return -a;
}
static final int safeAbs(int a) throws ArithmeticException {
  if (a == Integer.MIN_VALUE) {
    throw new ArithmeticException("Integer overflow");
  }
  return Math.abs(a);
}

public static int multAccum(int oldAcc, int newVal, int scale)
                  throws ArithmeticException {
  return safeAdd(oldAcc, safeMultiply(newVal, scale));
}

public static int multAccum(int oldAcc, int newVal, int scale) {
  return Math.addExact(oldAcc,               throws ArithmeticException {
  return Math.addExact(oldAcc, Math.multiplyExact(newVal, Math.multiplyExact(newVal, scale));
}

public static long intRangeCheck(long value)
                   throws ArithmeticException {
  if ((value < Integer.MIN_VALUE) || (value > Integer.MAX_VALUE)) {
    throw new ArithmeticException("Integer overflow");
  }
  return value;
}

public static int multAccum(int oldAcc, int newVal, int scale)
                  throws ArithmeticException scale) {
  final long res = intRangeCheck(
   ((long) oldAcc) + intRangeCheck((long) newVal * (long) scale)
  );
  return (int) res; // Safe downcast
}

private static final BigInteger bigMaxInt = 
  BigInteger.valueOf(Integer.MAX_VALUE);
private static final BigInteger bigMinInt =    
  BigInteger.valueOf(Integer.MIN_VALUE);

public static BigInteger intRangeCheck(BigInteger val)
                         throws ArithmeticException {
  if (val.compareTo(bigMaxInt) == 1 ||
      val.compareTo(bigMinInt) == -1) {
    throw new ArithmeticException("Integer overflow");
  }
  return val;
}

public static int multAccum(int oldAcc, int newVal, int scale)
                            throws ArithmeticException {
  BigInteger product =
    BigInteger.valueOf(newVal).multiply(BigInteger.valueOf(scale));
  BigInteger res = 
    intRangeCheck(BigInteger.valueOf(oldAcc).add(product));
  return res.intValue(); // Safe conversion
}