Java Goals

Java General Goals

• A comprehensive programming language.
• Platform independent.
• For both online (applets) and offline applications.
• Object-oriented.
• Easy to learn and use.
• Less pitfalls of other languages.
• Code portability.
• Auto Garbage Collection.
• Multi-threading.
• Better code security.
• JVM for both software and hardware.

Java Virtual Machine

• An application.
• Define instruction set(CPU).
• Define register set.
• Define class file format.
• Define stack.
• Define Garbage collected heap.
• Define memory area.
• Maintain proper type discipline from bytecodes.
• Check majority of type checking.
• Wider compliance for other JVM if approved by Sun.

Garbage Collection

• Deallocate memory that is no longer needed automatically.
• Provide a system-level thread to track memory allocation.
• Different JVM has different Garbage Collection algorithm.

Java Runtime Environment

• Load code.
• Verify code.
• Execute code.
• Installed in client machine for running Java applications.