Can you explain what a call stack in JVM is and how it functions?

The JVM call stack is a data structure that stores information about methods currently being executed in a thread. Each method call pushes a new frame (or stack frame) onto the stack, which contains local variables, parameters, and return address.

How it works:

• When a method is called, the JVM creates a new frame and pushes it onto the top of the stack.
• During method execution, data from this frame is used.
• When the method finishes, the frame is popped from the stack, and control returns to the previous method.

This allows the JVM to track the sequence of calls, manage local data, and ensure correct return from methods.

Example: if method A calls method B, the stack will first contain a frame for A, then a frame for B on top. After B finishes, its frame is removed, and execution continues in A.