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Application initialization – Apple WebObjects 3.5 User Manual

Page 47

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Initialization and Deallocation Methods

47

- awake {

/* initializations go here */

}

public void awake () {

/* initializations go here. */

}

Application Initialization

The application

init

method is invoked only once, when the application is

launched. You perform two main tasks in the application’s

init

method:

Initialize application variables

Configure applicationwide settings

For example, the Visitors application has this

init

method in

Application.wos

:

// WebScript Visitors Application.wos
- init {

[super init];
lastVisitor = @"";
[self setTimeOut:7200];
return self;

}

// Java Visitors Application.java
public Application () {

super();
...
lastVisitor = "";
setTimeOut(7200);
...

}

This method begins by calling the application’s

init

method. Then, it

initializes the application variable

lastVisitor

to be the empty string. (The

application has just started, so there has been no last visitor.) Finally, it sets
the application to terminate after it has been running 2 hours.

This example sets the application time-out value. You might want to do
other configurations in the application object’s

init

method as well. For

example, you can control how pages and components are cached and how
state is stored. For more information, read the chapter “Managing State”
(page 109).

The application’s

awake

method is invoked at the start of every cycle of the

request-response loop. Therefore, in the

awake

method, you perform

anything that should happen before each and every user request is
processed. For example, the DodgeDemo example application keeps track
of the number of requests the application has received. It increments and
logs that number at the top of the request-response loop: