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Java Virtual Machine - the java Stack

When a new thread is launched, the Java Virtual Machine creates a new java stack and program counter for the thread. A Java stack stores a thread's state in discrete frames, the java virtual machine only performs two operations directly on Java Stacks: it pushes and pops frames.

The method that is currently being executed by a thread is the thread's current method. The class in which the current method is defined is called the current clas, and the current class's constant pool is the current constant pool.

When a thread invokes a java method, the virtual machine creates and pushes a new frame onto the thread's java stack. This new frame becomes the current frame. As the method executes, it uses the frame to store parameters, local variables, intermediate computations, and other data.

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