(Multiple Browser Supported) Java applet using XHTML 'object' tag

This Java applet uses the Java Plug-in supplied by Sun. It has been tested and shown to work with the following browsers:
Microsoft Internet Explorer, Firefox, Mozilla, Camino, Netscape, Safari, Konqueror, and Opera.

NOTE: Need Java 1.4 (or later version) Plug-in to run this applet, so if it does not work, get the latest Java Plug-in here.

Applet source code Sample2.java:: jar file Sample2.jar

Here is the important XHTML source code

NOTE:

• The first key idea is to use nested objects. Microsoft Internet Explorer (MSIE) works by invoking the Java Plug-in ActiveX object GUID via the classid tag. The parameters to the Plug-in are then passed via the param tags. MSIE uses the inner nested object and Firefox/others will use the outer object.
  NOTE: When an applet's main class and its supporting classes are archived within a jar file, the Konqueror browser needs an archive parameter to be explicitly set to this jar file.
• By using classid="clsid:8AD9C840-044E-11D1-B3E9-00805F499D93", the latest installed version of the Java plug-in is used. For further information, see Using OBJECT, EMBED and APPLET Tags in Java Plug-in .
• The second key idea is to use Internet Explorer's Conditional Comments (see below) so that MS IE will ignore the outer object. Otherwise MS IE will try and produce two objects/applets. MS IE will not see the outer object because of the conditional Comments. Firefox/others will not do anything with the inner nested object (they will not understand the ActiveX object GUID classid tag) and will use only the outer object.
• The conditional comments begin like this:
  <!--[if !IE]>
  and end like this:
  <![endif]-->
• Firefox/others will use the outer object to active the Java Plug-in.

NOTE: (Extra Features for handling Java Plug-in problems)
The example code that follows uses features that aid the user if their browser either does not have a Java Plug-in or has an older version of the Java Plug-in.

• By using

  codebase="http://java.sun.com/update/1.5.0/jinstall-1_5_0-windows-i586.cab"
  

  Microsoft Internet Explorer will automatically get the Java 1.5 Plug-in. Getting the Java 1.5 Plug-in will occur when the browser either does not have a Java Plug-in or when the browser has an earlier version of the Java Plug-in than is needed. For further information, see Using OBJECT, EMBED and APPLET Tags in Java Plug-in .
• By putting this code within the inner nested object

              <strong>
                This browser does not have a Java Plug-in.
                <br />
                <a href="http://java.sun.com/products/plugin/downloads/index.html">
                  Get the latest Java Plug-in here.
                </a>
              </strong>
  

  If the browser is Firefox/others and there is no Java Plug-in then the user will be told this and a link to the latest Java Plug-in will be provided.

Example Code
(using Extra Features for handling Java Plug-in problems)

• The main class is Sample2 and it and its supporting classes are NOT archived within a jar file.
  • HTML (using applet tag)

            <!-- Compatible with all browsers --> 
            <applet code="Sample2" 
                    height="300" width="550" >
            </applet>
    

  • XHTML (using object tag)

          <!--[if !IE]> Firefox and others will use outer object -->
          <object classid="java:Sample2.class" 
                  type="application/x-java-applet"
                  height="300" width="550" >
          <!--<![endif]-->
            <!-- MSIE (Microsoft Internet Explorer) will use inner object --> 
            <object classid="clsid:8AD9C840-044E-11D1-B3E9-00805F499D93" 
                    codebase="http://java.sun.com/update/1.5.0/jinstall-1_5_0-windows-i586.cab"
                    height="300" width="550" > 
              <param name="code" value="Sample2" />
              <strong>
                This browser does not have a Java Plug-in.
                <br />
                <a href="http://java.sun.com/products/plugin/downloads/index.html">
                  Get the latest Java Plug-in here.
                </a>
              </strong>
            </object> 
          <!--[if !IE]> close outer object -->
          </object>
          <!--<![endif]-->
    

• The main class is Sample2 and it and its supporting classes are archived within a jar file named Sample2.jar.
  • HTML (using applet tag)

            <!-- Compatible with all browsers --> 
            <applet code="Sample2" 
                    archive="Sample2.jar"
                    height="300" width="550" >
            </applet>
    

  • XHTML (using object tag)

          <!--[if !IE]> Firefox and others will use outer object -->
          <object classid="java:Sample2.class" 
                  type="application/x-java-applet"
                  archive="Sample2.jar" 
                  height="300" width="550" >
            <!-- Konqueror browser needs the following param -->
            <param name="archive" value="Sample2.jar" />
          <!--<![endif]-->
            <!-- MSIE (Microsoft Internet Explorer) will use inner object --> 
            <object classid="clsid:8AD9C840-044E-11D1-B3E9-00805F499D93" 
                    codebase="http://java.sun.com/update/1.5.0/jinstall-1_5_0-windows-i586.cab"
                    height="300" width="550" > 
              <param name="code" value="Sample2" />
              <param name="archive" value="Sample2.jar" />
              <strong>
                This browser does not have a Java Plug-in.
                <br />
                <a href="http://java.sun.com/products/plugin/downloads/index.html">
                  Get the latest Java Plug-in here.
                </a>
              </strong>
            </object> 
          <!--[if !IE]> close outer object -->
          </object>
          <!--<![endif]-->
    

Advantages of using the Extra Features for handling Java Plug-in problems

• If the browser is Microsoft Internet Explorer and
  1. the user does not have a Java Plug-in OR
  2. the applet requires a later version of the Java Plug-in
  then the user will be prompted to download a recent version of the Java Plug-in.
  In this case the plug-in for Java 1.5
• If the browser is Firefox/others, and there is no Java Plug-in, then the user will be given a link to the latest Java Plug-in.
• If the browser is Firefox/others, and there is an older Java Plug-in than is needed, then the applet will not work, so be sure to include a NOTE above your applet telling the user where to go if the applet does not work. See the NOTE over the applet above for an example.