Java/J2ME/Date
Содержание
Date Field
<source lang="java">
/*--------------------------------------------------
- Snooze.java
- Example from the book: Core J2ME Technology
- Copyright John W. Muchow http://www.CoreJ2ME.ru
- You may use/modify for any non-commercial purpose
- -------------------------------------------------*/
import java.util.*; import javax.microedition.midlet.*; import javax.microedition.lcdui.*; import java.util.Timer; import java.util.TimerTask; public class Snooze extends MIDlet implements ItemStateListener, CommandListener {
private Display display; // Reference to display object
private Form fmMain; // The main form
private Command cmSnooze; // Start the timer
private Command cmReset; // Reset to current date/time
private Command cmExit; // Exit the MIDlet
private DateField dfSnoozeTime; // How long to snooze
private int dateIndex; // Index of the DateField on the Form
private Date currentTime; // Current time...changes when pressing reset
private Timer tmSnooze; // The timer - keeps track of system time
private SnoozeTimer ttSnooze; // Called by the timer
private boolean dateOK = false; // Was the user input valid?
public Snooze()
{
display = Display.getDisplay(this);
// The main form
fmMain = new Form("When to sound the alarm:");
// Save today"s date
currentTime = new Date();
// DateField with todays date as a default
dfSnoozeTime = new DateField("", DateField.DATE_TIME);
dfSnoozeTime.setDate(currentTime);
// All the commands/buttons
cmSnooze = new Command("Snooze", Command.SCREEN, 1);
cmReset = new Command("Reset", Command.SCREEN, 1);
cmExit = new Command("Exit", Command.EXIT, 1);
// Add to form and listen for events
dateIndex = fmMain.append(dfSnoozeTime);
fmMain.addCommand(cmSnooze);
fmMain.addCommand(cmReset);
fmMain.addCommand(cmExit);
fmMain.setCommandListener(this);
fmMain.setItemStateListener(this);
}
public void startApp ()
{
display.setCurrent(fmMain);
}
public void pauseApp()
{ }
public void destroyApp(boolean unconditional)
{ }
public void itemStateChanged(Item item)
{
if (item == dfSnoozeTime)
{
// If the user selected date and/or time that is earlier
// than today, set a flag. We are using getTime()
// method of the Date class, which returns the # of
// milliseconds since January 1, 1970
if (dfSnoozeTime.getDate().getTime() < currentTime.getTime())
dateOK = false;
else
dateOK = true;
}
}
public void commandAction(Command c, Displayable s)
{
if (c == cmSnooze)
{
if (dateOK == false)
{
Alert al = new Alert("Unable to set alarm", "Please choose another date and time.", null, null);
al.setTimeout(Alert.FOREVER);
al.setType(AlertType.ERROR);
display.setCurrent(al);
}
else
{
// Create a new timer
tmSnooze = new Timer();
ttSnooze = new SnoozeTimer();
// Amount of time to delay
long amount = dfSnoozeTime.getDate().getTime() - currentTime.getTime();
tmSnooze.schedule(ttSnooze,amount);
// Remove the commands
fmMain.removeCommand(cmSnooze);
fmMain.removeCommand(cmReset);
// Remove the DateField
fmMain.delete(dateIndex);
// Change the Form message
fmMain.setTitle("Snoozing...");
}
}
else if (c == cmReset)
{
// Reset to the current date/time
dfSnoozeTime.setDate(currentTime = new Date());
}
else if (c == cmExit)
{
destroyApp(false);
notifyDestroyed();
}
}
// Handle the timer task
private class SnoozeTimer extends TimerTask
{
public final void run()
{
Alert al = new Alert("Time to wake up!");
al.setTimeout(Alert.FOREVER);
al.setType(AlertType.ALARM);
AlertType.ERROR.playSound(display);
display.setCurrent(al);
// Cancel this timer task
cancel();
}
}
}
</source>
Date Today
<source lang="java">
//jad file (please verify the jar size) /* MIDlet-Name: DateToday MIDlet-Version: 1.0 MIDlet-Vendor: MyCompany MIDlet-Jar-URL: DateToday.jar MIDlet-1: DateToday, , DateToday MicroEdition-Configuration: CLDC-1.0 MicroEdition-Profile: MIDP-1.0 MIDlet-JAR-SIZE: 100
- /
import java.util.Date; import javax.microedition.lcdui.rumand; import javax.microedition.lcdui.rumandListener; import javax.microedition.lcdui.DateField; import javax.microedition.lcdui.Display; import javax.microedition.lcdui.Displayable; import javax.microedition.lcdui.Form; import javax.microedition.midlet.MIDlet; public class DateToday extends MIDlet implements CommandListener {
private Display display;
private Form form = new Form("Today"s Date");
private Date today = new Date(System.currentTimeMillis());
private Command exit = new Command("Exit", Command.EXIT, 1);
private DateField datefield = new DateField("", DateField.DATE_TIME);
public DateToday() {
display = Display.getDisplay(this);
datefield.setDate(today);
form.append(datefield);
form.addCommand(exit);
form.setCommandListener(this);
}
public void startApp() {
display.setCurrent(form);
}
public void pauseApp() {
}
public void destroyApp(boolean unconditional) {
}
public void commandAction(Command command, Displayable displayable) {
if (command == exit) {
destroyApp(false);
notifyDestroyed();
}
}
}
</source>
KVM Calendar
<source lang="java">
import java.util.Calendar; import java.util.Date; public class KVMCalendar {
public static void main(String[] args) {
Calendar cal = Calendar.getInstance();
Date date = new Date();
cal.setTime(date);
int month = cal.get(Calendar.MONTH);
int day = cal.get(Calendar.DAY_OF_MONTH);
System.out.println("Day is " + day + ", month is " + month);
final long MILLIS_PER_DAY = 24 * 60 * 60 * 1000L;
long offset = date.getTime();
offset += 20 * MILLIS_PER_DAY;
date.setTime(offset);
cal.setTime(date);
month = cal.get(Calendar.MONTH);
day = cal.get(Calendar.DAY_OF_MONTH);
System.out.println("In 20 days time, day will " + day + ", month will be " + month);
System.out.println(cal);
}
}
</source>
KVM Time Zones
<source lang="java">
import java.util.TimeZone; public class KVMTimeZones {
public static void main(String[] args) {
TimeZone defaultTZ = TimeZone.getDefault();
String[] ids = TimeZone.getAvailableIDs();
System.out.println("Available time zone ids: ");
for (int i = 0; i < ids.length; i++) {
System.out.print(ids[i] + " ");
}
System.out.println("\nDefault timezone is " + defaultTZ.getID() +
", GMT offset = " + defaultTZ.getRawOffset());
}
}
</source>
