datetimedemo.java

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        dateStyleMenu= new Choice();
	dateStyleMenu.addItemListener(this);
        dateStyleMenu.addItem("Full");
        dateStyleMenu.addItem("Long");
        dateStyleMenu.addItem("Default");
        dateStyleMenu.addItem("Short");
        dateStylePanel.add("loc",dateStyleLabel);
        dateStylePanel.add(dateStyleMenu);

        Panel timeStylePanel=new Panel();
        timeStylePanel.setLayout(new GridLayout(2,1));
        timeStyleLabel=new Label("Time Style");
        timeStyleLabel.setFont(Utility.labelFont);
        timeStyleMenu= new Choice();
	timeStyleMenu.addItemListener(this);
        timeStyleMenu.addItem("Full");
        timeStyleMenu.addItem("Long");
        timeStyleMenu.addItem("Default");
        timeStyleMenu.addItem("Short");
        timeStylePanel.add("loc",timeStyleLabel);
        timeStylePanel.add(timeStyleMenu);

        Panel dtStylePanel = new Panel();
        dtStylePanel.setLayout(new GridLayout(1,2,20,0));
        dtStylePanel.add(dateStylePanel);
        dtStylePanel.add(timeStylePanel);

        formatPanel.add(formatButtons);
        formatPanel.add(dtStylePanel);
        Utility.fixGrid(formatPanel,1);

        Panel localesFormatPanel = new Panel();

        localesFormatPanel.add(localePanel);
        localesFormatPanel.add(formatPanel);
        Utility.fixGrid(localesFormatPanel,1);
         add(localesFormatPanel);

        Panel copyrightPanel = new Panel();
        addWithFont (copyrightPanel,new Label(copyrightString, Label.LEFT),
            Utility.creditFont);
        addWithFont (copyrightPanel,new Label(copyrightString2, Label.LEFT),
            Utility.creditFont);
        Utility.fixGrid(copyrightPanel,1);
         add(copyrightPanel);

        //}}

    }


  /* ActionListener method */
  public void actionPerformed(ActionEvent e) {
    if (e.getSource() == up){
      dateFieldChanged(true);
    } else if (e.getSource() == down) {
      dateFieldChanged(false);
    }
  }

  /* ItemListener method */
  public void itemStateChanged(ItemEvent e) {
    if (e.getSource() == localeMenu) {
      selectedLocaleMenu();
    } else if (e.getSource() == dateStyleMenu) {
      selectedDateStyleMenu();
    } else if (e.getSource() == timeStyleMenu) {
      selectedTimeStyleMenu();
    } else if (e.getSource() == cityMenu) {
      cityChanged();
    } else if (e.getSource() == getRoll) {
      clickedGetRoll();
    } else if (e.getSource() == getAdd) {
      clickedGetAdd();
    } else if (e.getSource() == getLocalized) {
      isLocalized = getLocalized.getState();
      handleNewFormat();
    } else if (e.getSource() == getValidationMode) {
      validationMode = getValidationMode.getState();
      validationModeChanged();      
    } else if (e.getSource() == getDateInstance) {
      clickedGetDateFormat();
    } else if (e.getSource() == getTimeInstance) {
      clickedGetTimeFormat();
    } else if (e.getSource() == getDateTimeInstance) {
      clickedGetDateTimeFormat();
    }
 
  }
  
  /* KeyListener methods */
  public void keyPressed(KeyEvent e) {
  }

  public void keyReleased(KeyEvent e) {
    if (e.getSource() == patternText) {
      e.consume();
      patternTextChanged();
    } else if (e.getSource() == inputText) {
      e.consume();
      formatText();
    } else if (e.getSource() == outputText) {
      e.consume();
      parseText();
    } else if (e.getSource() == millisText) {
      e.consume();
      millisChanged();
    }
  }

  public void keyTyped(KeyEvent e) {
  }
  
  /* Window Listener methods */
  public void windowClosed(WindowEvent e) {
  }

  public void windowDeiconified(WindowEvent e) {
  }

  public void windowIconified(WindowEvent e) {
  }

  public void windowActivated(WindowEvent e) {
  }

  public void windowDeactivated(WindowEvent e) {
  }

  public void windowOpened(WindowEvent e) {
  }

  public void windowClosing(WindowEvent e) {
    setVisible(false);
    dispose();

    if (applet != null) {
      applet.demoClosed();
    } else System.exit(0);

  }


    /**
     * This function is called when users select a new time and/or date
     * format pattern, or a new locale.
     */
    public void setFormatFromLocale(boolean localChanged) {
        int localeIndex = localeMenu.getSelectedIndex();
        int dateStyleIndex = dateStyleMenu.getSelectedIndex()
                             + DateFormat.FULL;
        int timeStyleIndex = timeStyleMenu.getSelectedIndex()
                             + DateFormat.FULL;
        if (localChanged)
            // Find the locale corresponding to the selected menu item
            curLocale = locales[localeIndex];

        if (getDateInstance.getState()) {
            format =
            (SimpleDateFormat) DateFormat.getDateInstance(dateStyleIndex,
                                                        curLocale);
        } else if (getTimeInstance.getState()) {
            format =
            (SimpleDateFormat) DateFormat.getTimeInstance(timeStyleIndex,
                                                        curLocale);
        } else {
            format =
            (SimpleDateFormat) DateFormat.getDateTimeInstance(dateStyleIndex,
                                                            timeStyleIndex,
                                                            curLocale);
        }

        patternText.setText( format.toPattern() );
        if (!localChanged)
        {
            // locale not changed, only pattern format is changed.
            setMillisText();
            millisFormat();
        }
        else // change to selecting a rep. city based on new locale selected
        {
            cityMenu.select(kAdjCityIndex[localeIndex]);
            cityChanged();
        }
    }

    /**
     * This function is called when users change the pattern text.
     */
    public void setFormatFromPattern() {
        String timePattern = patternText.getText();
        format.applyPattern(timePattern);
        millisFormat();
        millisParse();
    }

    private boolean add = false;

    /**
     * This function is called when the "Roll" radio button is selected.
     */
    public  void clickedGetRoll() {
        add=false;
    }

    /**
     * This function is called when the "Add" radio button is selected.
     */
    public void clickedGetAdd() {
        add=true;
    }

    /**
     * This function is called when the "Date Format" radio button is selected.
     */
    public void clickedGetDateFormat() {
        setFormatFromLocale(false);
    }

    /**
     * This function is called when the "Time Format" radio button is selected.
     */
    public void clickedGetTimeFormat() {
        setFormatFromLocale(false);
    }

    /**
     * This function is called when the "Date and Time Format" radio button
     * is selected.
     */
    public void clickedGetDateTimeFormat() {
        setFormatFromLocale(false);
    }

    /**
     * This function is called when a new locale is selected.
     */
    public void selectedLocaleMenu() {
        setFormatFromLocale(true);
    }

    /**
     * This function is called when a new Date (Format) Style is selected.
     */
    public void selectedDateStyleMenu() {
        setFormatFromLocale(false);
    }

    /**
     * This function is called when a new Time (Format) Style is selected.
     */
    public void selectedTimeStyleMenu() {
        setFormatFromLocale(false);
    }

    /**
     * Store the current time in milliseconds.
     */
    long time = System.currentTimeMillis();

    /**
     * This function is called when it is necessary to parse the time
     * string in the "1.0 Date" text field.
     */
    public void formatText() {
        String leftString = inputText.getText();
        if (leftString.length() == 0)
        {
            errorText("Error: no input to format!");
            return;
        }

        try {
	  // intentional use of deprecated method
	  time = Date.parse(leftString); 
        }
        catch (Exception e) {
            outputText.setText("ERROR");
            errorText("Exception: Date.parse: "+leftString);
            return;
        }
        setMillisText();
        millisFormat();
    }

    /**
     * This function is called when it is necessary to parse the time
     * string in the "New Date" text field.
     */
    public void parseText() {
        String rightString = outputText.getText();

        ParsePosition status = new ParsePosition(0);

        if (rightString.length() == 0)
        {
            errorText("Error: no input to parse!");
            return;
        }

        try {
            time = format.parse(rightString, status).getTime();
        }
        catch (Exception e) {
            inputText.setText("ERROR");
            errorText("Exception: parse: "+rightString);
            return;
        }
        setMillisText();
        millisParse();

    }

    /**
     * This function is called when it is necessary to format the time
     * in the "Millis" text field.
     */
    public void millisFormat() {
        String out = "";
        try {
            out = format.format(new Date(time));
        }
        catch (Exception e) {
            outputText.setText("ERROR");
            errorText("Exception: format: "+time);
            return;
        }
        outputText.setText( out );
        errorText("Formatted...");
    }

    /**
     * This function is called when it is necessary to display the time
     * value parsed using GMT string in the "1.0 Date" text field.
     */
    public void millisParse() {
        String input = "";
        try {
	  // intentional use of deprecated method
	  input = new Date(time).toGMTString(); 
            }
        catch (Exception e) {
            inputText.setText("ERROR");
            errorText("Exception: in toGMTString: "+time); 
            return;
        }
        inputText.setText( input );
        errorText("Parsed...");
    }

    /**
     * This function is called when the time value in the "Millis" text field
     * is changed. The new time value will be formatted and displayed in both
     * "New Date" and "1.0 Date" text fields.
     */
    public void millisChanged() {
        String millisString = millisText.getText();
        try {
            time = Long.parseLong(millisString);
            }
        catch (Exception e) {
            errorText("Exception: Bad value for millis. Must be Long");
            return;
        }
        millisFormat();
        millisParse();
        errorText("Millis changed...");
    }

    /**
     * This function is called when it is necessary to display the time
     * value in milliseconds in the "Millis" text field.
     */
    public void setMillisText() {
        millisText.setText(Long.toString(time));
    }

    /**
     * This function is called when users change the pattern text.
     */
    public void patternTextChanged() {
        setFormatFromPattern();
    }

    /**
     * This function is called when users select a new representative city.
     */
    public void cityChanged() {
        int index = cityMenu.getSelectedIndex();

        SimpleTimeZone timeZone = new SimpleTimeZone(kZoneOffsets[index],
                                                     kZoneIDs[index]);
        timeZone.setStartRule(Calendar.APRIL, 1, Calendar.SUNDAY,
            2 * millisPerHour);
        timeZone.setEndRule(Calendar.OCTOBER, -1, Calendar.SUNDAY,
            2 * millisPerHour);

        format.setTimeZone(timeZone);

        millisFormat();
        millisParse();
    }

    private boolean addMode() {
        return add;
    }

    /**
     * This function is called when users select a new time field
     * to add or roll its value.
     */
    public void dateFieldChanged(boolean up) {
        String d = dateMenu.getSelectedItem();
        byte field = 0;

        if (d.equals("Year")) {
            field = (byte) Calendar.YEAR;
        } else
        if (d.equals("Month")) {
            field = (byte) Calendar.MONTH;
        } else
        if (d.equals("Day of Month")) {
            field = (byte) Calendar.DATE;
        } else
        if (d.equals("Hour of Day")) {
            field = (byte) Calendar.HOUR_OF_DAY;
        } else
        if (d.equals("Minute")) {
            field = (byte) Calendar.MINUTE;
        } else
        if (d.equals("Second")) {
            field = (byte) Calendar.SECOND;
        } else
        if (d.equals("Millisecond")) {
            field = (byte) Calendar.MILLISECOND;
        }

        format.getCalendar().setTime(new Date(time));
	//        format.getCalendar().computeFields();

        if (up) {
            if (addMode()) {
                format.getCalendar().add(field, 1);
            } else {
                format.getCalendar().roll(field, true);
            }
        } else {
            if (addMode()) {
                format.getCalendar().add(field, -1);
            } else {
                format.getCalendar().roll(field, false);
            }
        }

        time = format.getCalendar().getTime().getTime();

        setMillisText();

        millisFormat();

        millisParse();

    }

    /**
     * Print out the error message while debugging this program.
     */
    public void errorText(String s)
    {
        if (DEBUG)
        {
            System.out.println(s);
        }
    }

}