Still celebrating National IT Professionals Day with 3 months of free Premium Membership. Use Code ITDAY17

x
?
Solved

STRINGS AND NUMBERS

Posted on 1998-07-06
1
Medium Priority
?
252 Views
Last Modified: 2010-03-30
I am producing a simple Applet where the user enters a number into a text field and the computer performs some basic mathematics on the number entered. The problem is that the only commands that I can find for getting ands setting the field are 'getText' and 'setText'. These two commands only work on strimng value and I cannot find any Java commands for switching between strings and numbers.

Any help would be much appreiated.

Richard H
0
Comment
Question by:RICHARDH
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
1 Comment
 
LVL 6

Accepted Solution

by:
gadio earned 90 total points
ID: 1224713
RICHARDH, what you need is to use the formatters that java provides. The formatters are part of the java.text package. Here is an samll example of how to use diferent types of them:
---------
    //.....
    //Formatters to format and parse numbers
    private NumberFormat moneyFormatter;
    private NumberFormat percentFormatter;
    private NumberFormat integerFormatter;
    private DateFormat dateFormatter;

    //.....
    //.....
    private void setUpFormatters() {
        dateFormatter = new SimpleDateFormat("dd/MM/yy HH:mm");

        moneyFormatter = NumberFormat.getCurrencyInstance(Locale.US);

        percentFormatter = NumberFormat.getPercentInstance(Locale.US);
        percentFormatter.setMinimumFractionDigits(3);

        integerFormatter = NumberFormat.getNumberInstance(Locale.US);
        integerFormatter.setParseIntegerOnly(true);
    }
    //.....
    //.....
    //.....
   
        // using a formatter inside some function:
        // theformatter is one of the formatters instances defined above.
        public void actionPerformed(ActionEvent evt) {

            JTextField inputField = (JTextField)evt.getSource();

            try {
                if( theformatter instanceof NumberFormat ) {
                    NumberFormat formatter = (NumberFormat)theformatter;
                    Number value = formatter.parse(inputField.getText());
                    if (inputField == amountField)
                        amount = value.doubleValue();
                    else if (inputField == rateField)
                        rate = value.doubleValue();
                    else if (inputField == numPeriodsField)
                        numPeriods = value.intValue();
   
                    //Recalculate
                    payment = computePayment(amount, rate, numPeriods);

                    // Display
                    paymentField.setText(moneyFormatter.format(payment));
                }
                else {
                    DateFormat formatter = (DateFormat)theformatter;
                    Date value = formatter.parse(inputField.getText());

                    // Display
                    paymentField.setText(dateFormatter.format(value));
                }
            } catch (ParseException e) {
                Toolkit.getDefaultToolkit().beep();
                paymentField.setText("Input Error");
            }
        }
    }
-----------------------------
Hope that will help you.
G.
0

Featured Post

Build and deliver software with DevOps

A digital transformation requires faster time to market, shorter software development lifecycles, and the ability to adapt rapidly to changing customer demands. DevOps provides the solution.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

After being asked a question last year, I went into one of my moods where I did some research and code just for the fun and learning of it all.  Subsequently, from this journey, I put together this article on "Range Searching Using Visual Basic.NET …
Java functions are among the best things for programmers to work with as Java sites can be very easy to read and prepare. Java especially simplifies many processes in the coding industry as it helps integrate many forms of technology and different d…
Viewers will learn about the different types of variables in Java and how to declare them. Decide the type of variable desired: Put the keyword corresponding to the type of variable in front of the variable name: Use the equal sign to assign a v…
This tutorial covers a step-by-step guide to install VisualVM launcher in eclipse.
Suggested Courses

721 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question