APPLET
PROGRAMMING
IN
JAVA
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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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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

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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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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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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IV. METHODS: LIFE
CYCLE OF AN APPLET
A. Init
B. Start
C. Stop
D. Destroy
E. Paint
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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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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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Thank you.
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