Compare substring with string?

Why isn't it working?

Java Code:

                                 if ((line.substring(i,i+2)) == "go")
                                                break;

I printed this to check if substring works fine, used this:

Java Code:

   System.out.println(line.substring(i,i+2) + " : "+ length);

So, output:

Er : 1

ra : 2

ag : 3

go : 4

on : 5

n' : 6

'> : 7

Line:

String line = "Eragon'>";

Shouldn't it break loop after printing "go : 4"?

line.substring(i,i+2) prints go here. But if doesn't work.

What is wrong?