CODEWITHSUNDEEP
javacountif-statement
Mike
Mike

Reputation: 2313

Counting characters in java

I don't know how to insert a line of code that counts the numbers entered in a box that pops up. Basically I can't enter more than 5 numbers. So I think some sort of if statement needs to be inputed, which I don't know how to do.

Here is my code:

String number;


number = JOptionPane.showInputDialog("Enter Number");       


JOptionPane.showMessageDialog(null,"The new result is" + number,"Results",
        JOptionPane.PLAIN_MESSAGE);

        System.exit(0);

Thanks

Upvotes: 0

Views: 851

Answers (2)

Bala R
Bala R

Reputation: 108957

EDIT: a little shabby but how about something like this?

while(true)
{
    String number = JOptionPane.showInputDialog("Enter Number");       

    if(number.length() >5 )
    {

        JOptionPane.showMessageDialog(null ,"Too Long! try again",JOptionPane.PLAIN_MESSAGE);
    }
    else break;
}

Upvotes: 1

Erik
Erik

Reputation: 2051

There are some complications to this, you don't check for non-numeric characters, for instance. 

String number = JOptionPane.showInputDialog("Enter number");

number = number.trim(); // remove any spaces before and after
if (number.length() > 5 || hasNonNumeric(String)) {
   // show message
   JOptionPane.showMessageDialog(null,"Too long or non numeric characters in the string", 
   JOptionPane.PLAIN_MESSAGE);
}

boolean hasNonNumeric(String pSrc) {
    for (char c : pSrc.toCharArray()) {
        if (!Character.isDigit(c)) {
            return true;
        }
    }
    return false;
}

This is a bit safer.

Upvotes: 0

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