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Java Applets

} else {

//no way to detect!

return false;

}

This function uses object detection to determine which methodology to use. If

navigator.mimeTypes

available, then the function checks for an installed plugin using Netscape-style plugin detection. If, on

the other hand, it’s possible to create

ActiveXObject

objects, it uses the IE-style of detection. If neither

of these options is available (which isn’t very likely), the function just returns

false

To detect specific plugins, you can customize this algorithm and create a whole host of plugin detection

functions.

Java Applets

The oldest form of plugin, the Java applet has recently been redefined to work with the generic browser

plugin framework. Previously, applets had to be loaded using the

element. HTML 4.0 depre-

cated

, favoring

as the sole means for embedding plugins. To aid in this move,

Sun Microsystems created the Java Plugin, which is included as part of the Java Runtime Environment

(JRE) and is available at

http://java.sun.com/

Embedding applets

Embedding an applet requires you to use the nonstandard

code

property of

to specify the

class to load. Although all browsers should work when using

data

for the same purpose, the reality is

that support isn’t yet universal. So, in the interest of cross-browser compatibility, it’s best to use

code

in this way:

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

</object>

Note the mime type for Java applets is

application/x-java-applet

. By specifying this, you are sure

that the browser will use the most appropriate (and available) version of the Java plugin. You can

optionally specify the exact version required by adding it to the end of the mime type. For example, to

specify version 1.4.2 (from JRE 1.4.2), add

“jpi-version=1.4.2”

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

</object>

Macromedia provides a Flash Detection Kit, available at

http://www.macromedia

.com/software/flash/download/detection_kit

/, which can be used to produce

cross-browser HTML and JavaScript for embedding Flash movies.

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Interacting with Plugins

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