Apple WebObjects 3.5 - Manual (Page 39)

Client-Side Java Components
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When you look at client-side component’s bindings in the .wod file, it looks
like this example:
INPUTFIELD : WOApplet {
code = "next.wo.client.controls.TextFieldApplet.class";
codebase = "/WebObjects/Java";
archive = "woextensions.jar";
width = "200";
height = "20";
associationClass = "next.wo.client.SimpleAssociation";
stringValue = inputString
};
Like any other server-side dynamic element, the WOApplet’s definition
contains a list of attributes bound to constants or variables in the
component’s code.
The code attribute specifies which client-side component this WOApplet
should download. The codebase attribute specifies the path of the component
relative to your web server’s document root. (For the provided client-side
components, this path is always
/WebObjects/Java .)
The archive attribute specifies .jar files that should be preloaded onto the
client machine. If you don’t use this attribute, the applet downloads Java
.class files from the server one by one as it needs them. With the archive
attribute, you can package all necessary Java classes into archive files, and
they are downloaded once. However, only web browsers that have Java 1.1
support can use
.jar files. Because Java 1.1 is fairly new, there’s a good chance
your users use browsers that don’t support .jar files. All of the provided
client-side components are packaged in a single archive file named
woextensions.jar .
The associationClass attribute differentiates the client-side components from
any other applet you might include in your application. This attribute
specifies an object (a subclass of
next.wo.client.Association ) that the component
uses to communicate with the application on the server. The Association
object can get and set component state and cause methods to be invoked in
the server when actions are triggered in the client. For the WebObjects-
provided client-side components, this attribute is always
next.wo.client.SimpleAssociation . If you create your own client-side components,
you provide your own Association subclass.
The final attribute, stringValue , is an attribute specific to the TextFieldApplet
component. The Association object assigns the value of the inputString
variable to be the value of the text field on the client and keeps the two
objects in sync so that they always have the same value.