CallableTaskletAdapter Spring Batch

Question

Does CallableTaskletAdapter use a separate thread than the step itself?

    @Bean
    public Callable<RepeatStatus> callableObject() {

        return () -> {
            System.out.println(Thread.currentThread().getName());
            System.out.println("This was executed in another thread");

            return RepeatStatus.FINISHED;
        };
    }

    @Bean
    public CallableTaskletAdapter tasklet() {
        CallableTaskletAdapter callableTaskletAdapter =new CallableTaskletAdapter();

        callableTaskletAdapter.setCallable(callableObject());

        return callableTaskletAdapter;
    }
@Bean
    public Step callableStep() {
        System.out.println(Thread.currentThread().getName());
        return this.stepBuilderFactory.get("callableStep")
                .tasklet(tasklet())
                .build();
    }

Running this code prints the thread name as "main" in callable tasklet. Which means it is not using the new thread. Am I missing something?

Answer 1

Does CallableTaskletAdapter use a separate thread than the step itself?

No, it does not use a separate thread. It calls Callable#call using the thread executing the tasklet.