The ParaChat Java chat client is a 100% Java application. By its nature, the Java applet is very secure. An applet runs in a "sandbox" inside a browser, where no file operation is allowed. Nor can an applet read or write files, and this eliminates the vast majority of security problems that exist on the Internet today.
Additionally, an applet cannot open a network connection other than with the originating host server. For example, the applet HTML uses a codebase URL from which the Java class files are downloaded directly.