How to "throw out the new ZygoteInit.MethodAndArgsCaller" to clear the stacks of frames?

Question

I am a beginner of Java and Android, and I was puzzled after reading the Zygote code init.

After Zygote expands the child process, in the end invokeStaticMain, he throws

throw new ZygoteInit.MethodAndArgsCaller(m, argv)

which is handled by a catch block that executes the child process ZygoteInit.main

catch (MethodAndArgsCaller caller) {
    caller.run();
}

Comments throw new ZygoteInit.MethodAndArgsCallersay that it will clear all the frames of the stack that were necessary when setting up the process.

But I can’t understand how frame stacks are cleared. I checked a related SO question, What are ZygoteInit calls? , but neither the question nor its answer explain the cleaning work.

Does an exception help with stack recycling?

Answer 1

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