Why is Thread not an abstract class and start() not final?

Question

Why was the Thread class implemented as a regular class and not an abstract class with run() method being abstract.

Will it po

Answer 1

Why is Thread.start() not final?

Are you sure you would never want to override it?

Class MyThreadFactory implements ThreadFactory {
    @Override
    public Thread newThread(Runnable r) {
        return new Thread(r) {
            @Override
            public void start() {
                LOGGER.info("Starting thread " + this);
                super.start();
            }
        };
    }
}