This document discusses applet programming in Java. It provides an overview of applets and how they work as small applications accessed over the internet. It then discusses the key aspects of applet programming including the different ways to run an applet using a web browser or applet viewer, the steps to iterate through applet development by editing, compiling and executing code, and the lifecycle methods an applet can use like init, start, stop and destroy. It also covers event handling and the different event types applets can respond to like key and mouse events.

1. APPLET
PROGRAMMING
IN
JAVA
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2. OVERVIEW
 Applets
 Ways for running an applet
 Steps to iterate through applet development
 Methods: life cycle of an applet
 Event handling
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3. I. APPLETS
 Small applications accessed on Internet server, transported over Internet,
automatically installed and run as part of a Web document
 must be a subclass of the java.applet.Applet class
Simple applet overview-
Note the following considerations for this program-
oTwo import statements used:
oClass SimpleApplet is declared public to be accessed by code outside the
program

4. APPLETS (CONTINUED)
 Class SimpleApplet is also declared public
 paint( ) is declared inside SimpleApplet defined by the AWT
 paint( ) is called-
o Each time when applet must redisplay output
o When applet begins execution
 A call to drawString( ) inside paint( ), is a member of Graphics class
that outputs a string beginning at the specified X, Y location.
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5. II. WAYS FOR
RUNNING AN APPLET
Execution
within a Java
compatible
Web browser
Using an applet
viewer
A. Execution via Web browser-
<applet code= “SimpleApplet” width=200 height=60>
</applet>
B. Via an applet viewer-
o Applet executed in a window via Applet viewer using Command prompt
Example: if preceeding HTML file is called Run.html, SimpleApplet can run by the
following code-
C:>appletviewer Run
o Fastest and easiest way to test Applet
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6. III. STEPS TO ITERATE THROUGH
APPLET DEVELOPMENT
Edit a Java source file
Compile your program
Execute applet viewer specifying
name of applet’s source file
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7. IV. METHODS: LIFE
CYCLE OF AN APPLET
A. Init
B. Start
C. Stop
D. Destroy
E. Paint
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8. VI. EVENT HANDLING
 Mechanism used to handle events
 Key events in java:
o ActionEvent
o ItemEvent
o TextEvent
o WindowEvent
o KeyEvent
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9. CONCLUSION
Applets are one of the beauty under java programming language which
provide means to distribute interesting dynamic interactive application
over world wide web
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10. Thank you.
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