title: Spring Boot: Scalable tasks like Threads - how to do?
body: <p>I am starting with Spring Boot and want to execute tasks.</p>
  <p>Lets say my application knows different clients. For any client I like to do a periodic action (e.g. check a mail-account every minute). The number of clients may vary during the execution of the application (e.g. out of a DB table that grows or shrinks in time).</p>
  <p>In a &quot;normal&quot; program I would start a thread for any client that does the mail-handling inside a endless loop with a delay. During execution the number of threads would vary.</p>
  <p>How can I do such tasks with Spring Boot?
  I would expect some tools beside threads out of the framework.</p>
  <p>I know Components with @Scheduled but that is static and not dynamically to control (as far I know).</p>