From Forum Nokia Wiki

ID	CS001311	Creation date	March 30, 2009
Platform	S60 3rd Edition, S60 5th Edition, S40 2nd Edition, S40 3rd Edition, FP1	Tested on devices	Nokia E70, Nokia 5800 XpressMusic, Nokia 6021, Nokia 6131
Category	Java ME	Subcategory	PIM

Keywords (APIs, classes, methods, functions): java.util.Date, javax.microedition.lcdui.DateField, java.util.Calendar, java.util.Date

Overview

This code snippet demonstrates different ways to display date and time.

J2ME contains time and date in the Date class. There are different ways to display date and time:

1. The main way is to use the DateField UI control (see the outputDateUsingDateField method in this snippet). This control gets an instance of the Date class and displays its date and time in a formatted way, also allowing the changing of particular parts of this date.
2. The other way is to use the Date.toString() method. This method returns a textual representation of the date in string form, which can be used to display it or for other purposes. See the outputDateUsingToString method in this snippet.
3. If custom formatting of the date string is needed, the Calendar class can be used. For example, the outputDateUsingCalendar method of this snippet constructs a textual representation of the specified date, using the Calendar class to get particular parts of the date and using the StringBuffer class to construct a string from these parts of the date. It is not possible to create a textual representation of the date from a pattern string (such as "dd/mm/yyyy") in J2ME, but it can be easily implemented using the Calendar class.

Source file: DateAndTimeMidlet.java

/**
     * Sets up the main form.
     */
    private void setupMainForm() {
        mainForm = new Form("Date and time");
 
        // Get current date and output it by several ways.
        Date date = new Date();
 
        outputDateUsingDateField(date);
        outputDateUsingToString(date);
        outputDateUsingCalendar(date);
 
        mainForm.addCommand(EXIT_COMMAND);
        mainForm.setCommandListener(this);
    }
 
    /**
     * Shows specified date using DateField UI control.
     * @param date - date for showing
     */
    private void outputDateUsingDateField(Date date) {
        DateField field = new DateField("Using DateField", 
            DateField.DATE_TIME);
        field.setDate(date);
        mainForm.append(field);
    }
 
    /**
     * Converts specified date to string using Date.toString() method and
     * shows it using StringItem.
     * @param date
     */
    private void outputDateUsingToString(Date date) {
        StringItem item = new StringItem("Using .toString()", date.toString());
        mainForm.append(item);
    }
 
    /**
     * Constructs textual representation of specified date using Calendar class
     * for getting particular parts of date and using StringBuffer class 
     * to construct string from these parts of date.
     * @param date
     */
    private void outputDateUsingCalendar(Date date) {
        Calendar calendar = Calendar.getInstance();
        calendar.setTime(date);
        StringBuffer sb = new StringBuffer();
 
        int day = calendar.get(Calendar.DAY_OF_MONTH);
        sb.append(numberToString(day));
        sb.append("-");
        int month = calendar.get(Calendar.MONTH) + 1;
        sb.append(numberToString(month));
        sb.append("-");
        sb.append(calendar.get(Calendar.YEAR));
 
        StringItem item = new StringItem("Using Calendar", sb.toString());
        mainForm.append(item);
    }
 
    /**
     * Utility method. Converts number to string and adds '0' before it if this
     * number is less than 10.
     * @param value number to convert.
     * @return textual representation of value.
     */
    private String numberToString(int value) {
        String valStr = Integer.toString(value);
        return (value < 10) ? "0" + valStr: valStr;
    }

Postconditions

After launching the snippet - several controls are placed on the form of this snippet demonstrating different ways to create a textual representation of date and time and to display it for the user.

Supplementary material

This code snippet is part of the stub concept, which means that it has been patched on top of a template application in order to be more useful for developers. The version of the Java ME stub application used as a template in this snippet is v1.1.

• The patched, executable application that can be used to test the features described in this snippet is available for download at Media:DisplayingDateAndTime.zip.
• You can view all the changes that are required to implement the above-mentioned features. The changes are provided in unified diff and colour-coded diff (HTML) formats in Media:DisplayingDateAndTime.diff.zip.
• For general information on applying the patch, see Using Diffs.
• For unpatched stub applications, see Example stub.