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Referencing applets in JavaScript

In this mime type, JPI is short for

Java PlugIn

and it ensures that the applet is not run unless the plugin

on the user ’s computer is exactly equal to version 1.4.2. So even if the user has version 1.4.3, the applet

does not run. For this reason, it’s best to omit the plugin version to avoid any annoyance for your users.

The applet class can be contained within a JAR (Java Archive) file. In that case, specify the JAR file by

using the

archive

attribute:

archive=”ExampleArchive.jar”

code=”ExampleApplet.class” width=”100” height=”100” id=”ExampleApplet”>

</object>

To support Netscape Navigator 4.x, you use the original

element. To ensure that the code

works in all browsers, you can embed

inside of

(similar to the way you can

place

inside of

). However, doing so requires the use of the IE-proprietary

element. Although Mozilla and other browsers ignore content inside of

, IE

doesn’t, and could end up rendering two copies of the same applet. Inserting the

element

tells IE to ignore the extra content:

code=”ExampleApplet.class” width=”100” height=”100” id=”ExampleApplet”>

<applet code=”ExampleApplet.class” width=”100” height=”100”

name=”ExampleApplet”></applet>

</comment>

</object>

Referencing applets in JavaScript

After an applet has been included in an HTML page, you need a way to access it via JavaScript.

Traditionally, applets were referenced through the

document.applets

collection, which indexed all

elements by their name attribute and position in the document (similar to

document.forms

and

document.frames

). For example, to get a reference to an applet with the

name

attribute set to

“ExampleApplet”

, you could do the following:

var oApplet = document.applets[“ExampleApplet”];

However, if you use the

element to embed applets, the

document.applets

collection doesn’t

include it. When using

, you can access the applet using

document.getElementById()

var oApplet = document.getElementById(“ExampleApplet”);

If you are using both

and

for compatibility with older browsers, you should use

a function to determine the appropriate method:

function getApplet(sName) {

if (document.getElementById) {

return document.getElementById(sName);

} else {

return document.applets[sName];

}

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