The Java EE 5 Tutorial

Including an Applet

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

     { 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> }

The jsp:plugin tag is replaced by either an <object> or an <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 override the default URL where the plug-in can be downloaded.

The jsp:params element specifies 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 because of 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 pop-up window reporting a ClassNotFoundException.

The Duke’s Bookstore page /template/prelude.jspf creates the banner that displays a dynamic digital clock generated by DigitalClock (see Figure 5–3).

Figure 5–3 Duke’s Bookstore with Applet

Screen capture of Duke's Bookstore with "Web Components
for Web Developers" recommendation, "Start Shopping" link and date and time

Here is the jsp:plugin element that is used to download the applet:

     align="center" height="25" width="300"
     iepluginurl="" >
        <jsp:param name="language"
            value="${pageContext.request.locale.language}" />
        <jsp:param name="country"
            value="${}" />
        <jsp:param name="bgcolor" value="FFFFFF" />
        <jsp:param name="fgcolor" value="CC0066" />
        <p>Unable to start plugin.</p>