Security in Java™

Security is extremely important as the Internet grows. Java protects users against nasty Java code via a number of methods. The Java compiler and run time system implements several layers of defense against potentially incorrect code. First, memory layout is deferred to run time, guarding against altered compilers. Also, Java programmers are opaque to the memory allocation and referencing model which is controlled entirely by the underlying run-time system.

Secondly, the Java run-time system subjects incoming code to bytecode verification. The range of tests makes sure the code does not forge pointers and doesn't violate access restrictions. Thirdly, the Java bytecode loader ensures that classes don't violate access restrictions or name space when they are loaded into the system. There is one name space for classes that come from the local file system, and a separate name space for each network source. Finally, the API specific security prevents applets from doing destructive things.

Java is secure to survive in the network-based environment. So far people on the Internet have sacrificed security for maximum flexibility. Java can help enable much better security.

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