Multithreading 1 quiz - Thread::run

[tfwongao]

For the Multithreading 1 quiz on Nov 8, it was mentioned that "We cannot call Thread::run but should call Thread::start. JVM will automatically call Thread::run after initializing the thread. We never call Thread::run ourselves"
However, while I am testing out, (option 1) Thread t = new Thread(this); t.run(); runs successfully just like (option 5) this.run(); with thread ID same as the main thread ID (A new thread has not been created). Should we consider option 1 correct as well?

[sccust]

Thanks for your checking. You are right. The first answer has the similar effect as the last answer on the slide. If a thread's start method is not called, Java does not perform a context switching to a new call stack, and therefore the run method is run at the current call stack; in this example, it is the one used by the main thread. Without context switching to a new call stack, the effect is essentially like no new created thread.

I have updated the finalreview slides at the course web page with additional comment for classmates' reference. In this examination, I will clarify the questions to minimize possible confusion. There will be a paper checking session after we have released the score, and classmates can appeal should we have missed correct answers in the grading. We will regrade a question for the whole class if we have made mistakes on it.

Hope it clarifies.