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The APPLET HTML Tag

Applets are included on web pages using the tag. The tag is perhaps most similar to the tag. Like needs to reference a source file that is not part of the HTML page on which it is embedded. IMG’s do this with the SRC= parameter. APPLET’s do this with the CODE= parameter. The CODE parameter tells the browser where to look for the compiled .class file. It is relative to the location of the source document. Thus if you’re browsing http://metalab.unc.edu/javafaq/index.html and that page references an applet with CODE=animation.class, then the animation.class file needs to be at http://metalab.unc.edu/javafaq/animation.class.

For reasons that remain a mystery to HTML authors everywhere, but possibly having something to do with packages and classpaths, if the applet resides somewhere other than the same directory as the page it lives on, then you don’t just give a URL to its location. Rather you point at the directory where the .class file is using the CODEBASE parameter. You still also have to use CODE to give name of the .class file.

Also like IMG, APPLET has several parameters to define how it is positioned on the page. HEIGHT and WIDTH parameters work exactly as they do with IMG, specifying how big a rectangle the browser should leave for the applet. These numbers are specified in pixels. ALIGN also works exactly as for images (in those browsers that support ALIGN) defining how the applet’s rectangle is placed on the page relative to other elements. Possible values include LEFT, RIGHT, TOP, TEXTTOP, MIDDLE, ABSMIDDLE, BASELINE, BOTTOM and ABSBOTTOM. Finally as with IMG you can specify an HSPACE and a VSPACE in pixels to set the amount of blank space between an applet and the surrounding text.

Finally also like IMG, APPLET has an ALT tag. As far as I know ALT is not yet implemented in any browsers. An ALT tag is used by a browser that understands the APPLET tag but for some reason cannot play the applet. For instance if an applet needs to write a file on your hard drive, but your preferences are set not to allow that, then the browser should display the ALT text.

ALT is not used for browsers that do not understand APPLET at all. For that purpose APPLET has been defined to include a closing tag as well,

. All raw text between the opening and closing APPLET tags is ignored by a Java capable browser. However a non-Java capable browser will ignore the APPLET tags instead and read the text between them.

This entry was posted on Wednesday, July 29th, 2009 at 9:17 am and is filed under Uncategorized. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.

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