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Applet loading process

JClic was created with "Java", a programming tool that makes it possible for the aplications to work in different types of computers, operating systems and browsers. The "applets" are Java applications embedded in web pages.

For security reasons, our applets incorporate a digital signature which ensures that they have been created by the JClic development team and assures the privacy and integrity of your data.

When entering a page containing a JClic applet for the first time, a javascript module is executed in order to check if the computer has the Java 1.3.1 plug-in installed. When it is not found, a warning screen is displayed and the user is forwarded to the Java installation page.

The Java plug-in may need some seconds to start running. During this short period of time, a small grey rectangle will appear on the screen where the applet should appear. Once completely downloaded an icon will appear on the taskbar:

Icon with Java 1.3.1 Icon with Java 1.4 and 1.5

This icon will be shown while the browser window is open. If this icon is visible, the Java engine will be active and the applet downloading will be quicker.

Next a warning window will be displayed and you will be asked to accept the applet execution:

Choose Grant always and the JClic applets will run automatically and be kept in memory.

Once this screen is validated, the Java engine will download the necessary files to run JClic. This process can last a few minutes, depending on the connection to the Internet but only the first time you visit a JClic applet or when a new version is available on the server.

The last step consists in the downloading of the activity package you are visiting. This process will depend on the size of the package. There are activities that are completely downloaded from the beginning, others will download only the basic components at startup, getting the remaining elements  (images, sounds, ...) as they need them. In this case the package starts running more quickly but there can be some delay from one activity to the next.

An animation on the JClic taskbar indicates that a file is being downloaded and we must wait for it:

When the applet starts running you can move from one activity to another  by just using the JClic navigation buttons (not the browser navigation buttons!).

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