Comparison of Strings

[Cero.Uno]

I'm making a java console program, I'm taking input from the user however I want the program to only succeed if the selection given (string) is valid to the choices purposed from the console.

Code:

                printGameMenu();
		do
		{
			userChoice = getInput("Please make a selection");
		}
		while("".equals(userChoice));

Since I had problems using the != operator not working when comparing a string (nightmare), for the moment of learning I'm using the equals method, my question is what is the alternative method to equals?

I need this while loop to continue iterating WHILE the input is not equal to "q" or "p"

q for quitting the program and p for playing the game.

I need the opposite method to equals.

[hey]

Quote:

Originally Posted by Cero.Uno

I need the opposite method to equals.

Code:

while("".equals(userChoice)==false);

added: equals is the right thing to use, while comparing strings, when you do this ==,!= you compare addresses of the strings, not theactual strings (remember String is an object)

[tim]

Hello Cero.Uno

You can solve this problem simply by using boolean variables. The String.equals() method returns a boolean result of true if your Strings are equal in value.

Code:

boolean loop = true;
do{
    userChoice = getInput("Please make a selection");
    boolean quit = userChoice.equals("q");
    boolean play = userChoice.equals("p");
    loop = (quit || play) == false;
while (loop == true);

This code uses the logic operators || and ==. Google logic operators in Java, to find out more.

Good luck.

[Roughedge]

Dead easy, just put the '!' before your condition. For example:

Code:

public class TestApp 
{
    public static void main(String[] args)
    {
        int count = 0;
        System.out.println("Starting program");
        String testString1 = "hello";
        String testString2 = "world";
        
        while(!testString1.equals(testString2) && count != 2000)
        {
            count++;
            System.out.println("Number "+count+" This means it is not equal");
            
        }
    }

}

The count is there just to stop the infinite while loop that killed my computer!