Thread: For loop with a string as the subject

I am building a basic calculator and this is my first program in Java after reading about.. 2 tutorials and I am having a hard time getting the program to check the input on the string and run code if that input satisfies the condition.

The user inputs either +, -, * or /

I want to check to see if the input is a +, if it is then run the code. So far it runs no matter what you enter, null or otherwise.

Here is my code - let's not judge if it is crap.. you started this way (maybe);

import java.io.*;
 
public class Main {
 
public static void main (String args[]) throws IOException {
 
	InputStreamReader inStream = new InputStreamReader(System.in);
	BufferedReader readIN = new BufferedReader(inStream);
 
		System.out.println("Multiply | Divide | Add | Subtract");
		System.out.println("   *     |    /   |  +  |     -   ");
 
		try {
			System.out.println("What operation?");
 
			String oprt = readIN.readLine();
			/*if(oprt != null){
				System.out.println("Null entry detected.");
				System.out.println("End of program. Press any key to terminate.");
			}*/
			if("+".equals(oprt));{
				System.out.println("You selected addition!");
			}
			System.out.println( oprt );
		}
		catch (IOException err){
			System.out.println("Error reading input.");
		}
 
		System.out.println("End of program. Press any key to terminate.");
		String termin = readIN.readLine();
	}
 
}

Take a closer look at your if statement:

if("+".equals(oprt));{

You've to an extra ';' in there, which is causing the block of code immediately following it to execute no matter what. I assume that's what you mean by "it runs no matter what you enter".

Originally Posted by Fluidz

That is the biggest fail ever.

Cheers mate, and off topic: How come the code tags didn't highlight the java codes syntax? Is it [java][/java]?

I think what you're looking to do is [highlight=java]code goes here[/highlight]