Applet life cycle?
Applet life cycle: Every java applet inherits a set of default behaviours from the applet class. as a result, when an a...
https://www.computersprofessor.com/2017/01/applet-life-cycle.html
Applet life cycle:
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Every java
applet inherits a set of default behaviours from the applet class. as a
result, when an applet is loaded it undergoes a series of charged in its
state.
The applet
states include:
Born (or) initialization state.
running state.
idle state.
dead (or) destroyed state.
Initialization state:
Applet enters
the initialization state when it is first loaded. This is achieved by calling
the init() method of applet class. The applet is born. At this stage, we may
do the following if required.
create objects needed by the applet
set up initial values
load images or fonts
set up colours
The
initialization occurs only once in the applets life cycle. To provide any of
the behaviors mentioned above, we must override the init method.
public void
init()
{
----------
---------(action)
}
Running state:
Applet enters
the running state when the system calls the start( ) method of applet class.
This occurs automatically after the applet is initialized. Starting can also
occur if the applet is already “stopped” (idle) state. For example, we may leave the webpage
containing the applet temporarily to another page and return back to the
page. This again starts the applet running. Note that, unique init() method,
the start() method may be called more than once. We may override start()
method to create a thread to control the applet.
public void
start()
{
----------
---------
--------(action)
}
Idle (or) stopped state:
An applet becomes
idle when it is stopped from running. Stopping occurs automatically when we leave
the page containing the currently running applet. We can also do so by
calling the stop () method explicitly. If we use a thread to run the applet, then
we must use stop() method to terminate the thread. We can achieve this by
overriding the stop() method.
public void
stop()
{
---------
----------
---------(action)
}
Dead state:
An applet is
said to be dead when it is removed from memory. This occurs automatically, by
invoking the destroy() method when we quite the browser. Like initialization,
destroying stage occurs only once in the applets life cycle. If applet has
created any resources, like threads, we may over ride the destroy() method to
clean up these resources.
public void
destroy()
{
----------
----------(action)
}
Display state:
Applet moves
to the display state whenever it has to perform some output operations on the
screen. This happens immediately after the applet enters into the running state.
The point () method is called to accomplish this task. Atmost every applet
will have a point() method.
We must
therefore over ride this method if we want anything to be displayed on the
screen.
public void
point(Graphics g)
{
-----------
------------(display
statements)
}
It is to be
noted that the display state is not considered as a part of the applets life
cycle.
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