Academic Tutorials



English | French | Portugese | German | Italian
Home Advertise Payments Recommended Websites Interview Questions FAQs
News Source Codes E-Books Downloads Jobs Web Hosting
Chats

Java Tutorial
Java Introduction
Object Oriented Programming Concepts
Anatomy of a Java Application
Syntax and Semantics of Java
Java Objects, Classes, and Interfaces
The String and StringBuffer Classes in Java
Setting Program Attributes in Java
Using System Resources in Java
Threads of Control in Java
Errors and Exceptions in Java
Java Input and Output Streams
Overview of Java Applet
Creating an Applet User Interface in Java
Communicating with Other Programs in Java
Overview of the Java UI
Using GUI Building Blocks in Java
Laying Out Components within a Container
Working with Graphics in Java
How Java Differs from C and C++
Java Summary

HTML Tutorials
HTML Tutorial
XHTML Tutorial
CSS Tutorial
TCP/IP Tutorial
CSS 1.0
CSS 2.0
HLML
XML Tutorials
XML Tutorial
XSL Tutorial
XSLT Tutorial
DTD Tutorial
Schema Tutorial
XForms Tutorial
XSL-FO Tutorial
XML DOM Tutorial
XLink Tutorial
XQuery Tutorial
XPath Tutorial
XPointer Tutorial
RDF Tutorial
SOAP Tutorial
WSDL Tutorial
RSS Tutorial
WAP Tutorial
Web Services Tutorial
Browser Scripting
JavaScript Tutorial
VBScript Tutorial
DHTML Tutorial
HTML DOM Tutorial
WMLScript Tutorial
E4X Tutorial
Server Scripting
ASP Tutorial
PERL Tutorial
SQL Tutorial
ADO Tutorial
CVS
Python
Apple Script
PL/SQL Tutorial
SQL Server
PHP
.NET (dotnet)
Microsoft.Net
ASP.Net
.Net Mobile
C# : C Sharp
ADO.NET
VB.NET
VC++
Multimedia
SVG Tutorial
Flash Tutorial
Media Tutorial
SMIL Tutorial
Photoshop Tutorial
Gimp Tutorial
Matlab
Gnuplot Programming
GIF Animation Tutorial
Scientific Visualization Tutorial
Graphics
Web Building
Web Browsers
Web Hosting
W3C Tutorial
Web Building
Web Quality
Web Semantic
Web Careers
Weblogic Tutorial
SEO
Web Site Hosting
Domain Name
Java Tutorials
Java Tutorial
JSP Tutorial
Servlets Tutorial
Struts Tutorial
EJB Tutorial
JMS Tutorial
JMX Tutorial
Eclipse
J2ME
JBOSS
Programming Langauges
C Tutorial
C++ Tutorial
Visual Basic Tutorial
Data Structures Using C
Cobol
Assembly Language
Mainframe
Forth Programming
Lisp Programming
Pascal
Delphi
Fortran
OOPs
Data Warehousing
CGI Programming
Emacs Tutorial
Gnome
ILU
Soft Skills
Communication Skills
Time Management
Project Management
Team Work
Leadership Skills
Corporate Communication
Negotiation Skills
Database Tutorials
Oracle
MySQL
Operating System
BSD
Symbian
Unix
Internet
IP-Masquerading
IPC
MIDI
Software Testing
Testing
Firewalls
SAP Module
ERP
ABAP
Business Warehousing
SAP Basis
Material Management
Sales & Distribution
Human Resource
Netweaver
Customer Relationship Management
Production and Planning
Networking Programming
Corba Tutorial
Networking Tutorial
Microsoft Office
Microsoft Word
Microsoft Outlook
Microsoft PowerPoint
Microsoft Publisher
Microsoft Excel
Microsoft Front Page
Microsoft InfoPath
Microsoft Access
Accounting
Financial Accounting
Managerial Accounting
Network Sites


Overview of Java Applet


Previoushome Next





Most common Java programs are the applications and applets. Applications are the stand-alone programs, like HotJava browser.

A D V E R T I S E M E N T
Applets are similar to the applications, but they will not run on their own. Instead they adhere to a set of conventions which lets them run within the Java-compatible browser.



The Life Cycle of the Applet

Loading an Applet
When an applet is been loaded, this is what happens:

  • An instance of applet's controlling class is created.
  • The applet gets initialized itself.
  • The applet starts to run.

Leaving and Returning to Applet's Page
When user leaves the page -- say for example, to go to different page -- the applet has an option to stop by itself. When the user returns to the page, applet can do start by itself again. The same thing takes place when the user iconifies a browser window which contains the applet.

Reloading the Applet
Some browsers let the users to reload the applets, which consists of unloading applet and then loading it again. Before an applet is been unloaded, it is given the chance to stop itself and then perform the final cleanup, so that the applet can do release any of the resources it holds. After that the applet is unloaded and loaded as described in Loading the Applet, above.




Role of Threads in Applets

Every applet can do run in multiple threads. example: when a HotJava browser first views the document that contains an applet, browser's DocumentSwitcher thread executes an applet's init() method. And when user scrolls the document, AWT WServer thread executes an applet's update() method.

So why would a applet need to create and use its own threads? Imagine an applet that performs the time-consuming initialization -- like loading images -- in its init() method. The thread which invokes the init() method cannot do anything else until the init() returns. In the HotJava browser, this means that browser cannot display applet or anything after it until the applet has finished the initializing itself. Therefoer if an applet is at the top of the page, then nothing would appear on the page until the applet has finished initializing itself.

The solution to this is to create a thread and move the initialization code from the init() method into thread body.




What the Applets Can and Can't Do

The Security Restrictions
For the security reasons, an applet which is loaded over network has the following restrictions:

  • It cannot load the libraries or define native methods.
  • It cannot ordinarily read or write the files on host that is executing it.
  • It cannot make network connections except the host which it came from
  • It cannot start any program on the host which is executing it.
  • It cannot read every system property.
  • Windows which an applet brings up look different than windows which an aplication brings up.

Each browser do have a SecurityManager object which checks for the applet security violations. When a SecurityManager detects violation, it throws up an SecurityException.

The Applet Capabilities
Here are some of the other things that an applet can do which you might not expect:

  • Applets running within the Web browser can easily cause an HTML documents to be displayed.
  • Applets can do invoke the public methods of other applets on same page.
  • Applets that are loaded from local file system (from a directory in user's CLASSPATH) have none of the restrictions that applets loaded over the network do have.
  • Although most of the applets stop running once you leave their page.

The java.applet package provides the API that gives an applets some capabilities which applications dont have. as an applets can play sounds, which other programs cannot do.



Be the first one to comment on this page.




  Java Tutorial eBooks
More Links » »
 
 Java Tutorial FAQs
More Links » »
 
 Java Tutorial Interview Questions
More Links » »
 
 Java Tutorial Articles
More Links » »
 
 Java Tutorial News
More Links » »
 
 Java Tutorial Jobs
More Links » »

Share And Enjoy:These icons link to social bookmarking sites where readers can share and discover new web pages.
  • blinkbits
  • BlinkList
  • blogmarks
  • co.mments
  • connotea
  • del.icio.us
  • De.lirio.us
  • digg
  • Fark
  • feedmelinks
  • Furl
  • LinkaGoGo
  • Ma.gnolia
  • NewsVine
  • Netvouz
  • RawSugar
  • Reddit
  • scuttle
  • Shadows
  • Simpy
  • Smarking
  • Spurl
  • TailRank
  • Wists
  • YahooMyWeb

Previoushome Next

Keywords: java applet download, gameboyemu java applet, free java applet, java applet games, java applet package, java applet tutorial, loading java applet failed, java djvu viewer applet, java applet that will calculate when, java applet developer provides highly adaptive

HTML Quizzes
HTML Quiz
XHTML Quiz
CSS Quiz
TCP/IP Quiz
CSS 1.0 Quiz
CSS 2.0 Quiz
HLML Quiz
XML Quizzes
XML Quiz
XSL Quiz
XSLT Quiz
DTD Quiz
Schema Quiz
XForms Quiz
XSL-FO Quiz
XML DOM Quiz
XLink Quiz
XQuery Quiz
XPath Quiz
XPointer Quiz
RDF Quiz
SOAP Quiz
WSDL Quiz
RSS Quiz
WAP Quiz
Web Services Quiz
Browser Scripting Quizzes
JavaScript Quiz
VBScript Quiz
DHTML Quiz
HTML DOM Quiz
WMLScript Quiz
E4X Quiz
Server Scripting Quizzes
ASP Quiz
PERL Quiz
SQL Quiz
ADO Quiz
CVS Quiz
Python Quiz
Apple Script Quiz
PL/SQL Quiz
SQL Server Quiz
PHP Quiz
.NET (dotnet) Quizzes
Microsoft.Net Quiz
ASP.Net Quiz
.Net Mobile Quiz
C# : C Sharp Quiz
ADO.NET Quiz
VB.NET Quiz
VC++ Quiz
Multimedia Quizzes
SVG Quiz
Flash Quiz
Media Quiz
SMIL Quiz
Photoshop Quiz
Gimp Quiz
Matlab Quiz
Gnuplot Programming Quiz
GIF Animation Quiz
Scientific Visualization Quiz
Graphics Quiz
Web Building Quizzes
Web Browsers Quiz
Web Hosting Quiz
W3C Quiz
Web Building Quiz
Web Quality Quiz
Web Semantic Quiz
Web Careers Quiz
Weblogic Quiz
SEO Quiz
Web Site Hosting Quiz
Domain Name Quiz
Java Quizzes
Java Quiz
JSP Quiz
Servlets Quiz
Struts Quiz
EJB Quiz
JMS Quiz
JMX Quiz
Eclipse Quiz
J2ME Quiz
JBOSS Quiz
Programming Langauges Quizzes
C Quiz
C++ Quiz
Visual Basic Quiz
Data Structures Using C Quiz
Cobol Quiz
Assembly Language Quiz
Mainframe Quiz
Forth Programming Quiz
Lisp Programming Quiz
Pascal Quiz
Delphi Quiz
Fortran Quiz
OOPs Quiz
Data Warehousing Quiz
CGI Programming Quiz
Emacs Quiz
Gnome Quiz
ILU Quiz
Soft Skills Quizzes
Communication Skills Quiz
Time Management Quiz
Project Management Quiz
Team Work Quiz
Leadership Skills Quiz
Corporate Communication Quiz
Negotiation Skills Quiz
Database Quizzes
Oracle Quiz
MySQL Quiz
Operating System Quizzes
BSD Quiz
Symbian Quiz
Unix Quiz
Internet Quiz
IP-Masquerading Quiz
IPC Quiz
MIDI Quiz
Software Testing Quizzes
Testing Quiz
Firewalls Quiz
SAP Module Quizzes
ERP Quiz
ABAP Quiz
Business Warehousing Quiz
SAP Basis Quiz
Material Management Quiz
Sales & Distribution Quiz
Human Resource Quiz
Netweaver Quiz
Customer Relationship Management Quiz
Production and Planning Quiz
Networking Programming Quizzes
Corba Quiz
Networking Quiz
Microsoft Office Quizzes
Microsoft Word Quiz
Microsoft Outlook Quiz
Microsoft PowerPoint Quiz
Microsoft Publisher Quiz
Microsoft Excel Quiz
Microsoft Front Page Quiz
Microsoft InfoPath Quiz
Microsoft Access Quiz
Accounting Quizzes
Financial Accounting Quiz
Managerial Accounting Quiz
Testimonials | Contact Us | Link to Us | Site Map
Copyright 2008. Academic Tutorials.com. All rights reserved Privacy Policies | About Us
Our Portals : Academic Tutorials | Best eBooksworld | Beyond Stats | City Details | Interview Questions | Discussions World | Excellent Mobiles | Free Bangalore | Give Me The Code | Gog Logo | Indian Free Ads | Jobs Assist | New Interview Questions | One Stop FAQs | One Stop GATE | One Stop GRE | One Stop IAS | One Stop MBA | One Stop SAP | One Stop Testing | Webhosting in India | Dedicated Server in India | Sirf Dosti | Source Codes World | Tasty Food | Tech Archive | Testing Interview Questions | Tests World | The Galz | Top Masala | Vyom | Vyom eBooks | Vyom International | Vyom Links | Vyoms | Vyom World
Copyright 2003-2017 Vyom Technosoft Pvt. Ltd., All Rights Reserved.