Java programming calculator

I had to make a calculator using stacks. Here is what i have so far. For some reason, the equal sign doesn't work. Can someone help me fix this. The code shows no error,
http://pastebin.com/SjemnE0V

Use printf debugging: make calculate() show a popup when it is called to see if it is called right.  If that worked, then start putting them at different places throughout its logic and printing to see if it's doing what you expect.  For example, have it print str to see if it's really one of the values you expect.

Speaking of str, you should have a default fallthrough at the end of that if-else chain to print an error if it gets an unexpected value:

if(str.equals("-")){
    /* do stuff */
} else if(str.equals("+"){
    /* do stuff */
} else {
    show_popup("unexpected value of str: " + str);
}
And similarly in other places throughout your program.

>>1 posts a link to miserable pile of spaghetti.
>>2 suggests adding tumors.
>>3 tells >>1,2 to go back to /b/, please.

>>1
Thanks for reminding me why, after Lisp, I didn't look back.

>>2

java have no debuggers?

>>5
How does the code smell?


Sloooooow!

>>5

Why use a debugger when you have printf() System.out.println() SomeJavaGuiShit.MessageBoxFactory()?

When I saw ``Java programming calculator'', I immediately thought that it is a salary calculator for aspiring enterprise scalable n-tier turkey solutionist employees.

When I saw ``Java programming calculator'', I knew >>1-san came from /g/.

I'd tell >>1-san we don't help /g/aylords or any other retard with their homeworks but it doesn't matter anyway since they never listen.

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LELLLLLLLLLLLLLLLLLLLLLLLLLLLLLLL
>EGINWIMGOINGWIM /G/RO
>LE LEL FACE
>LEEEEEEEEEEEEEEEEEEEEEELLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLL

Super Turbo Turnkey Solution Provider THREE

String numbers[]={"0","1","2","3","4","5","6","7","8","9","+","-","*","/",".","CE","C","=","+/-"};

I don't think you belong here.

>>12
CE is a valid number and it means Current Era

>>13
In the case of calculators, it means "clear everything", and is definitely not a number.

Lies. It means CUNT EXTERMINATOR