public class Test {
    public static final int MASK_ULWALKABLE = 1;
    public static final int MASK_UNKNOWN = 2;
    public static final int MASK_UNDER_ROOF = 4;

    public static void main(String[] args){
        int value = 1;
        System.out.println("Value is = "+value);

        if((value & MASK_ULWALKABLE) == MASK_ULWALKABLE){
            System.out.println("Unwalkable");
        }
        if((value & MASK_UNKNOWN) == MASK_UNKNOWN){
            System.out.println("unknown flag is flagged");
        }
        if((value & MASK_UNDER_ROOF) == MASK_UNDER_ROOF){
            System.out.println("Under roof");
        }
    }
}

Value is = 1
Unwalkable

Value is = 2
unknown flag is flagged

Value is = 4
Under roof

Value is = 3
Unwalkable
unknown flag is flagged

Value is = 5
Unwalkable
Under roof

Value is = 7
Unwalkable
unknown flag is flagged
Under roof