Unsigned.java

/**
 * @author Joseph Cumbo (mooman219)
 */
public class Unsigned {

    public static void main(String[] args) {
        int test = Integer.MAX_VALUE;
        System.out.printf("0x%1$8X or %1$d\n", test);
        test++;
        System.out.printf("0x%1$8X or %1$d\n", test);
        System.out.printf("0x%1$8X or %1$d\n", asUnsignedInt(test));
    }

    public static long asUnsignedInt(int value) {
        return (value & Integer.MIN_VALUE) == Integer.MIN_VALUE // If the top bit is set
                ? (value & Integer.MAX_VALUE) + (0x80000000l) // Then, unset the top bit, then add Integer.MIN_VALUE as a long
                : value; // Else, just retun the value
    }
}

/*
 run:
 0x7FFFFFFF or 2147483647
 0x80000000 or -2147483648
 0x80000000 or 2147483648
 */