One of Java's design goals is to develop Applets. The so-called applet is a small program executed on a web browser. Because applet is absolutely safe, what you can do is limited.
1. APPLET
The execution of Applet is extremely limited, usually called "doing things in the sandbox", because there is an invisible guy (Java execution period security system) is warned.
2. Applet's goal
Applet is expected to expand the functionality of the web page in the browser.
3. APPLET limit
A. Applet can't touch this machine disk content - no matter whether you read and write, no one wants applet to read your personal secret data without permission; if you open your machine disk, you may bring viruses Intrusion. Java provides a digital signature feature for Applet, once the user selects the trusted Applet (provided by a trusted source visa) to access the machine, the applet is loosely.
B. It may take a long time to display Applet, because everything is downloaded every time, including the file request for each Class to another server. The browser can save the applet buffer (cache) in this machine, and if it does not guarantee it. Based on this reason, you should pack your Applet and all its constituent components (including other Class files, graphics files, audio files) in a single compressed JAR file, then just establish a single connection with the server. This file can be obtained. You can also provide a digital signature for each independent project in the JAR file.
4. Advantages of applet
If you can accept these restrictions, Applet has undoubted advantages in the following points - especially when developers from architecture or web applications.
A. No longer have problems, Applet has the ability to real with the platform (including easy play), so you don't need to modify the code for different platforms, and you will not let your users are upset because of the installation. In fact, when the user loads Applet, Automatically complete the installation. All updated movements have been unscrupulous.
B. No need to be a wrong program code to destroy others, because the security mechanism has been built into the core Java language and Applet organizations.
