messageformatdemo.java

JavaTM 2 SDK, Standard Edition Documentation

/*
 * @(#)MessageFormatDemo.java	1.1 96/11/23
 *
 * (C) Copyright Taligent, Inc. 1996 - All Rights Reserved
 * (C) Copyright IBM Corp. 1996 - All Rights Reserved
 *
 * Portions copyright (c) 1996 Sun Microsystems, Inc. All Rights Reserved.
 *
 *   The original version of this source code and documentation is copyrighted
 * and owned by Taligent, Inc., a wholly-owned subsidiary of IBM. These
 * materials are provided under terms of a License Agreement between Taligent
 * and Sun. This technology is protected by multiple US and International
 * patents. This notice and attribution to Taligent may not be removed.
 *   Taligent is a registered trademark of Taligent, Inc.
 *
 * Permission to use, copy, modify, and distribute this software
 * and its documentation for NON-COMMERCIAL purposes and without
 * fee is hereby granted provided that this copyright notice
 * appears in all copies. Please refer to the file "copyright.html"
 * for further important copyright and licensing information.
 *
 * SUN MAKES NO REPRESENTATIONS OR WARRANTIES ABOUT THE SUITABILITY OF
 * THE SOFTWARE, EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
 * TO THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
 * PARTICULAR PURPOSE, OR NON-INFRINGEMENT. SUN SHALL NOT BE LIABLE FOR
 * ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING OR
 * DISTRIBUTING THIS SOFTWARE OR ITS DERIVATIVES.
 *
 */

import java.applet.Applet;
import java.awt.event.*;
import java.awt.*;
import java.util.*;
import java.lang.*;
import java.text.*;

/**
 * <P> Pattern formats are used to put together sequences of strings, numbers,
 * dates, and other formats to create messages.  The pattern formatters
 * facilitate localization because they prevent both hard-coding of message
 * strings, <I> and </I> hard-coding of the concatenation sequence for portions
 * of message strings.  This means localizers can change the content, format,
 * and order of any text as appropriate for any language.
 * </P>
 * <P><CENTER>
 * <A HREF="#format">About the Pattern Format</A>&nbsp;
 * <A HREF="#arguments">Formatting Arguments</A><BR>
 * <A HREF="#choices">Supporting Multiple Choices</A>
 * </CENTER></P>
 * <HR>
 * <H3><A NAME="format">About the Pattern Format </A></H3>
 * <P> The pattern is a sequence of text and arguments, all of which can be
 * edited.  The positions of the arguments within the sequence are indicated
 * by a &quot;&#37;&quot; followed by a digit <I> n </I> identifying the
 * argument.  The pattern in the demo applet has three arguments, numbered 0,
 * 1, and 2.  The arguments can appear in any order within the sequence, which
 * can be edited and modified.
 * </P>
 * <TABLE WIDTH=100% CELLPADDING=5>
 * <TR>
 * <TH ALIGN=left VALIGN=bottom>To See This...</TH>
 * <TH ALIGN=left VALIGN=bottom>Do This...</TH>
 * </TR>
 * <TR>
 * <TD WIDTH=50% VALIGN=top> You can move arguments freely within the sequence
 * or delete arguments.  You can also edit or translate any of the unformatted
 * text.
 * </TD>
 * <TD VALIGN=top>
 * <TABLE CELLSPACING=0 CELLPADDING=0>
 * <TR>
 * <TD WIDTH=10 VALIGN=top> 1.
 * </TD>
 * <TD> Move the string &quot;on &#37;2&quot; from the end of the pattern to
 * the front and correct the capitalization
 * </TD>
 * </TR>
 * </TABLE>
 * </TD>
 * </TR>
 * <TD WIDTH=50% VALIGN=top> Translations are provided in the demo applet for
 * the G7 countries.
 * </TD>
 * <TD VALIGN=top>
 * <TABLE CELLSPACING=0 CELLPADDING=0>
 * <TR>
 * <TD WIDTH=10 VALIGN=top> 1.
 * </TD>
 * <TD> Pull down the Locale menu
 * </TD>
 * </TR>
 * <TR>
 * <TD WIDTH=10 VALIGN=top> 2.
 * </TD>
 * <TD> Try several different locales with the up and down arrow keys (on
 * Windows) or the mouse button (on Macintosh)
 * </TD>
 * </TR>
 * </TABLE>
 * </TD>
 * </TR>
 * </TABLE>
 * <P><STRONG><I>Note:</I></STRONG> To add a real percentage character to the
 * pattern, enter &quot;&#37;&#37;&quot;.
 * </P>
 * <HR WIDTH=50% ALIGN=left>
 * <H3><A NAME="arguments"> Formatting Arguments </A></H3>
 * <P> The arguments can be either simple text strings or formattable,
 * localizable objects.  The pattern in the demo applet, for example, includes
 * a date, an unformatted string, and a more complex format called a <I> choice
 * </I> format (described below).  You can edit these arguments at will.  When
 * localizing, you can also select any format to be associated with an
 * argument.
 * </P>
 * <TABLE WIDTH=100% CELLPADDING=5>
 * <TR>
 * <TH ALIGN=left VALIGN=bottom>To See This... </TH>
 * <TH ALIGN=left VALIGN=bottom>Do This...</TH>
 * </TR>
 * <TR>
 * <TD WIDTH=50% VALIGN=top> You can modify the value of any argument.
 * </TD>
 * <TD VALIGN=top>
 * <TABLE CELLSPACING=0 CELLPADDING=0>
 * <TR>
 * <TD WIDTH=10 VALIGN=top> 1.
 * </TD>
 * <TD> Select the &quot;3&quot; in argument 2 and change it to another number
 * &#151;the formatted date adjusts to the new value
 * </TD>
 * </TR>
 * </TABLE>
 * </TD>
 * </TR>
 * <TR>
 * <TD WIDTH=50% VALIGN=top> You can change the format of any argument, and can
 * specify &quot;unformatted&quot; arguments that are not localized.
 * </TD>
 * <TD VALIGN=top>
 * <TABLE CELLSPACING=0 CELLPADDING=0>
 * <TR>
 * <TD WIDTH=10 VALIGN=top> 1.
 * </TD>
 * <TD> Change the format type for argument 2 to <I> None </I>
 * </TD>
 * </TR>
 * <TR>
 * <TD WIDTH=10 VALIGN=top> 2.
 * </TD>
 * <TD> Try different locales and notice that the date does not reformat for
 * different locales
 * </TD>
 * </TR>
 * <TR>
 * <TD WIDTH=10 VALIGN=top> 3.
 * </TD>
 * <TD> Return the format back to <I>Date </I> and try different locales again.
 * The date reformats.
 * </TD>
 * </TR>
 * </TABLE>
 * </TD>
 * </TR>
 * </TABLE>
 * <HR WIDTH=50% ALIGN=left>
 * <H3> <A NAME="choices">Supporting Multiple Choices </A></H3>
 * <P> Choice formats, like that used for argument 0, let localizers create
 * more natural messages, avoiding phrases like &quot;3 file(s)&quot;.  As
 * shown here, the correct text can be chosen for different numbers.  This
 * works even in more complicated contexts, such as Slavic languages which
 * have more than one plural format based on the number involved.  A particular
 * choice is chosen based on the value of the argument, and each choice can be
 * edited individually.
 * </P>
 * <P> Look also at the format for the choice associated with values of 2 and
 * higher, &quot;&#37;0|3&quot;.  The vertical bar indicates that the choice
 * uses the value for argument 0, but the format for argument 3 (in this case,
 * a Number).  This allows for a degree of flexibility in using different
 * formats.
 * </P>
 * <TABLE WIDTH=100% CELLPADDING=5>
 * <TR>
 * <TH ALIGN=left VALIGN=bottom>To See This...</TH>
 * <TH ALIGN=left VALIGN=bottom>Do This... </TH>
 * </TR>
 * <TR>
 * <TD WIDTH=50% VALIGN=top> You can edit the value of any of the choice
 * options.
 * </TD>
 * <TD VALIGN=top>
 * <TABLE CELLSPACING=0 CELLPADDING=0>
 * <TR>
 * <TD WIDTH=10 VALIGN=top> 1.
 * </TD>
 * <TD> Select the Choice String &quot;no files&quot; and type in &quot;not a
 * single file&quot;
 * </TD>
 * </TR>
 * <TR>
 * <TD WIDTH=10 VALIGN=top> 2.
 * </TD>
 * <TD> Select the value for argument 0 and type in &quot;0&quot;
 * </TD>
 * </TR>
 * </TABLE>
 * </TD>
 * </TR>
 * <TR>
 * <TD WIDTH=50% VALIGN=top> You can establish different choices for parameters
 * based on the value of an argument, so that strings are substituted that
 * agree numerically.
 * </TD>
 * <TD VALIGN=top>
 * <TABLE CELLSPACING=0 CELLPADDING=0>
 * <TR>
 * <TD WIDTH=10 VALIGN=top> 1.
 * </TD>
 * <TD> Select the value for argument 0 and type in &quot;0&quot;, then replace
 * it with a &quot;1&quot;, and then with a &quot;2&quot;.  The string changes
 * correspondingly.
 * </TD>
 * </TR>
 * <TR>
 * <TD WIDTH=10 VALIGN=top> 2.
 * </TD>
 * <TD> Select argument 0 and return the value to &quot;0&quot;.  Choose the
 * French or German locale and notice that it makes correct substitutions in
 * any language.
 * </TD>
 * </TR>
 * </TABLE>
 * </TD>
 * </TR>
 * <TR>
 * <TD WIDTH=50% VALIGN=top> You can add as many alternatives as you need for
 * different value ranges.
 * </TD>
 * <TD VALIGN=top>
 * <TABLE CELLSPACING=0 CELLPADDING=0>
 * <TR>
 * <TD WIDTH=10 VALIGN=top> 1.
 * </TD>
 * <TD> Select the U.S. English locale
 * </TD>
 * </TR>
 * <TR>
 * <TD WIDTH=10 VALIGN=top> 2.
 * </TD>
 * <TD> Select the empty choice value box (under the &quot;2&quot;) and type
 * in &quot;10&quot;
 * </TD>
 * </TR>
 * <TR>
 * <TD WIDTH=10 VALIGN=top> 3.
 * </TD>
 * <TD> Type in &quot;many files&quot; in the corresponding <I> Choice Strings
 * </I> field
 * </TD>
 * </TR>
 * <TR>
 * <TD WIDTH=10 VALIGN=top> 4.
 * </TD>
 * <TD> Enter a number larger than10 for the value of argument 0&#151;&quot;
 * many files&quot; is substituted in the resulting message
 * </TD>
 * </TR>
 * </TABLE>
 * </TD>
 * </TR>
 * </TABLE>
 * <P>  You can type in other text in the pattern, arguments, or choices fields
 * to  see different formatting behaviors.  Try it out!
 * </P>
 * @see        java.util.Format
 * @see        java.util.MessageFormat
 * @version    1.1 11/23/96
 * @author     Laura Werner, Mark Davis
*/

public class MessageFormatDemo extends DemoApplet
{
    /**
     * The main function which defines the behavior of the MessageFormatDemo
     * applet when an applet is started.
     */
    public static void main(String argv[]) {
        DemoApplet.showDemo(new MessageFormatFrame(null));
    }

    /**
     * This creates a MessageFormatFrame for the demo applet.
     */
    public Frame createDemoFrame(DemoApplet applet) {
        return new MessageFormatFrame(applet);
    }
}

/**
 * A Frame is a top-level window with a title. The default layout for a frame
 * is BorderLayout.  The MessageFormatFrame class defines the window layout of
 * MessageFormatDemo.
 */
 class MessageFormatFrame extends Frame implements WindowListener, ItemListener, KeyListener {

    /**
     * Constructs a new MessageFormatFrame that is initially invisible.
     */
    public MessageFormatFrame(DemoApplet applet)
    {
        super("Message Formatting Demo");
        this.applet = applet;
	addWindowListener(this);
        init();
        start();
    }

    /**
     * Initializes the applet. You never need to call this directly, it
     * is called automatically by the system once the applet is created.
     */
    public void init() {

        //Get all locales for debugging, but only get G7 locales for demos.
        if (DEBUG == true)
             locales = NumberFormat.getAvailableLocales();
        else locales = Utility.getG7Locales();

        buildGUI();

    }

    /**
     * Called to start the applet. You never need to call this method
     * directly, it is called when the applet's document is visited.
     */
    public void start() {

        // Stick some initial data into the controls....
        arg1Text.setText("3");
        arg1Type.select(CHOICE);

        arg2Text.setText("MyDisk");
        arg2Type.select(NONE);

        arg3Text.setText("3 Mar 96");
        arg3Type.select(DATE);

        arg4Text.setText("");
        arg4Type.select(NUMBER);

        patternText.setText("The disk '%1' contained %0 on %2.");

        // Set up the choice format controls too
        choice1Num.setText("0");
        choice2Num.setText("1");
        choice3Num.setText("2");
        resetFormat();
        doFormatting();

    }

    /**
     * Reset to the default message format using the ResourceBundle mechanism.
     * @see java.util.ResourceBundle
     * @see java.util.ListResourceBundle
     */
    public void resetFormat() {
        Locale locale = locales[localeMenu.getSelectedIndex()];

	ClassLoader classLoader = this.getClass().getClassLoader();

        choice4Num.setText("");
        choice4Text.setText("");

        ResourceBundle choiceResources =
             ResourceBundle.getBundle("ChoiceResource", locale);

	patternText.setText(choiceResources.getString("patternText"));
        choice1Text.setText(choiceResources.getString("choice1"));
        choice2Text.setText(choiceResources.getString("choice2"));
        choice3Text.setText(choiceResources.getString("choice3"));
    }

    /**
     * Create a new format based on the selected type.  For example, a new
     * format needs to be created if a different locale or format type is
     * selected.
     */
    public Format createFormat(Choice typeMenu)
    {
        int type = typeMenu.getSelectedIndex();
        Locale locale = locales[localeMenu.getSelectedIndex()];

        Format result = null;
        if (type == NUMBER) {
            result = NumberFormat.getInstance(locale);
        }
        else if (type == DATE) {
            result = DateFormat.getDateInstance(DateFormat.DEFAULT, locale);
        }
        else if (type == CHOICE) {
            result = choiceFormat;    // XXX
        }
        return result;
    }

    /**
     * Create a new format based on the selection changes and update the
     * output text area.
     */
    public void doFormatting() {

        // Create a ChoiceFormat based on the settings in the choice field
        double[] limits = new double[4];
        limits[0] = doubleValue(choice1Num.getText());
        limits[1] = doubleValue(choice2Num.getText());
        limits[2] = doubleValue(choice3Num.getText());
        limits[3] = doubleValue(choice4Num.getText());

        String[] choices = new String[4];
        choices[0] = choice1Text.getText();
        choices[1] = choice2Text.getText();
        choices[2] = choice3Text.getText();
        choices[3] = choice4Text.getText();


        choiceFormat = new ChoiceFormat(limits, choices);    // XXX

        // Create the individual formatters for the items in the pattern....
        Format[] formats = new Format[4];
        formats[0] = createFormat(arg1Type);
        formats[1] = createFormat(arg2Type);
        formats[2] = createFormat(arg3Type);
        formats[3] = createFormat(arg4Type);

        // Now create the Message Formatter itself
        MessageFormat format = new MessageFormat(patternText.getText());

        // Create the array of objects to format....
        Object[] objects = new Object[4];
        objects[0] = createObject(arg1Type, arg1Text);
        objects[1] = createObject(arg2Type, arg2Text);
        objects[2] = createObject(arg3Type, arg3Text);
        objects[3] = createObject(arg4Type, arg4Text);

        String result = null;
        try {
            result = format.format(objects);
        }
        catch (Exception e)
        {
            errorText("format threw an exception: " + e.toString());
            result = "ERROR";
        }
        resultText.setText(result);
    }

  /* ItemListener method */
  public void itemStateChanged(ItemEvent e) {
    if((e.getSource() == arg1Type) || (e.getSource() == arg2Type) || (e.getSource() == arg3Type)
       || (e.getSource() == arg4Type)) {
      doFormatting();
    } else if (e.getSource() == localeMenu) {
      resetFormat();
      doFormatting();
    }
  }
  
  /* KeyListener methods */
  public void keyPressed(KeyEvent e) {
  }

  public void keyReleased(KeyEvent e) {
    if ((e.getSource() == choice1Text) || (e.getSource() == choice2Text) || 
	(e.getSource() == choice3Text) || (e.getSource() == choice4Text)) {
      e.consume();