Including an Applet

Including an Applet

You can include an applet or JavaBeans component in a JSP page using the jsp:plugin element. This element generates HTML that contains the appropriate client browser dependent constructs (<object> or <embed>) that will result in the download of the Java Plug-in software (if required) and client-side component and subsequent execution of an client-side component. The syntax for the jsp:plugin element follows:

<jsp:plugin 
    type="bean|applet" 
    code="objectCode" 
    codebase="objectCodebase" 
    { align="alignment" } 
    { archive="archiveList" } 
    { height="height" } 
    { hspace="hspace" } 
    { jreversion="jreversion" } 
    { name="componentName" } 
    { vspace="vspace" } 
    { width="width" } 
    { nspluginurl="url" } 
    { iepluginurl="url" } > 
    { <jsp:params> 
        { <jsp:param name="paramName" value= paramValue" /> }+ 
    </jsp:params> } 
    { <jsp:fallback> arbitrary_text </jsp:fallback> } 
</jsp:plugin>

The jsp:plugin tag is replaced by either an <object> or <embed> tag, as appropriate for the requesting client. The attributes of the jsp:plugin tag provide configuration data for the presentation of the element as well as the version of the plug-in required. The nspluginurl and iepluginurl attributes specify the URL where the plug-in can be downloaded.

The jsp:param elements specify parameters to the applet or JavaBeans component. The jsp:fallback element indicates the content to be used by the client browser if the plug-in cannot be started (either because <object> or <embed> is not supported by the client or due to some other problem).

If the plug-in can start but the applet or JavaBeans component cannot be found or started, a plug-in-specific message will be presented to the user, most likely a popup window reporting a ClassNotFoundException.

3. Duke's Bookstore with Applet

The Duke's Bookstore page banner.jsp that creates the banner displays a dynamic digital clock generated by DigitalClock:

The jsp:plugin element used to download the applet follows:

<jsp:plugin 
    type="applet" 
    code="DigitalClock.class" 
    codebase="/bookstore2" 
    jreversion="1.3" 
    align="center" height="25" width="300" 
    nspluginurl="http://java.sun.com/products/plugin/1.3.0_01 
        /plugin-install.html" 
    iepluginurl="http://java.sun.com/products/plugin/1.3.0_01 
        /jinstall-130_01-win32.cab#Version=1,3,0,1" > 
    <jsp:params> 
        <jsp:param name="language" 
            value="<%=request.getLocale().getLanguage()%>" /> 
        <jsp:param name="country" 
            value="<%=request.getLocale().getCountry()%>" /> 
        <jsp:param name="bgcolor" value="FFFFFF" /> 
        <jsp:param name="fgcolor" value="CC0066" /> 
    </jsp:params> 
        <jsp:fallback> 
        <p>Unable to start plugin.</p> 
    </jsp:fallback> 
</jsp:plugin>