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There are several predefined security managers available for certain types of applications. The applet security manager is used to manage all Java applets. It denies applets all but the most essential privileges. It is designed to protect prevent inadvertent system modification, information leakage and user impersonation. The use of security managers is not limited to client side protection. Webservers, such as Tomcat and Websphere, use this facility to isolate trojan servlets and malicious JSP code, as well as to protect sensitive system resources from inadvertent access.
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