-0 Java programming

[ShunpoHadouken]

Yey the program now runs but still the problem exist 
sorry for asking too much.
still the output is zero instead of invalid.

[Byakko]

What's your current code ?

[ShunpoHadouken]

Here 
public class Switch {
    public static void main(String[] args) {
String i = "-0";
if(i.length() >= 2 && i.substring(0,1) == "-" && i.substring(1,2) == "0")
{System.out.println("INVALID");}
else
{
int x=Integer.parseInt(i);
if (x>0)
{System.out.println("POSITIVE");}
else
    if (x<0)
    {System.out.println("NEGATIVE");}
    else
        {System.out.println("ZERO");}
}
}
}

[Byakko]

That's odd. After "String i = -0" and before the if test, try adding a println to display the values of "i.length()", of "i.substring(0,1)" and of "i.substring(1,2)", I might have messed up a number when I gave you that.

[Iced]

maybe you should try charat(number) instead, since its more straight forward?

[Valodim]

INDENTATION.

learn it, use it. now.

Also: if(i.equals("-0"))

[ShunpoHadouken]

public class Switch {
    public static void main(String[] args) {
String i = "-0";
if(i.equals("-0"))
{System.out.println("INVALID");}
else
{
int x=Integer.parseInt(i);
if (x>0)
{System.out.println("POSITIVE");}
else
    if (x<0)
    {System.out.println("NEGATIVE");}
    else
        {System.out.println("ZERO");}
}
}
}
Yehey! the program now works perfectly.
Thank you very much everyone that helped me.
thanks a lot.

Now this program is finished.
but, can i ask some last question. Please. 
I need this so that i can explain it to my professor when she ask me.
Why should I declare variable "i" as string? String i = "-0"; Is it so that java will read "-0" different form a "0".
Why should i declare variable "x" like this: int x=Integer.parseInt(i);? Is it to convert the string variable i to an integer?


thnaks a lot.

[Iced]

Why should I declare variable "i" as string? String i = "-0"; Is it so that java will read "-0" different form a "0".

Because if declared as a int, java will drop the signal and assume you meant zero only.So yes, if it was int i=-0, java would only read 0.

Why should i declare variable "x" like this: int x=Integer.parseInt(i);? Is it to convert the string variable i to an integer?

so that you convert the string into a integer, in case it wasnt -o.
If the value was coming from outside and you werent able to know what it was, it would help to have you test for the -0 first, then if it passes that test, you turn it into an integer ( parse it into integer) and continue testing the values.

[ShunpoHadouken]

Oh so that was it.
thank you.

Thanks Iced,Valodim,Byakko,Cybaster, thanks a lot for help!.