Create a new instance of component in Spring Boot/Framework

Question

In my Spring Boot based application I’ve a @Component class that has code similar to this:

ExecutorService executorService = Executors.newFixedThreadPool(poolSize);

// Start a separate thread for each entry
Map<Long, Future<Integer>> calls = new HashMap<>();

for (MyClass info : list) {
    Callable<Integer> callable = new TableProcessor(info);
    Future<Integer> future = executorService.submit(callable);
    calls.put(info.getId(), future);
}

The AutoWiring is not working in the TableProcessor class because (I think) I am creating an instance using ‘new’. What’s the best way to ‘create a new instance for each entry in my list’?

Note: Adding a ‘Bean’ to Application class won’t work in this case because I want a new instance for each thread.

Answer 1

I had a similar problem and I solved it using the ApplicationContext.

Here's an example because I like to look at code rather than explain things, so maybe it will help someone in the same boat:

First, here's the Spring component that I want to create a new instance of:

@Component
@Scope("prototype")
public class PopupWindow extends Window{

    private String someVar;

        @PostConstruct
        public void init(){
          //stuff
          someVar="hi";
    }
}

Here's the class where I want 2 instances of this Spring component:

@Component
@Scope("session")
public class MainWindow extends Window{

    private PopupWindow popupWindow1;
    private PopupWindow popupWindow2;

    @Autowired
    private ApplicationContext applicationContext;

        @PostConstruct
        public void init(){
          popupWindow1 = applicationContext.getBean(PopupWindow.class);
          popupWindow2 = applicationContext.getBean(PopupWindow.class);
    }
}

In my particular case, I'm using Vaadin + Spring, and these annotations use the Vaadin versions i.e. @SpringComponent and @UIScope instead of @Scope("session"). But the @Scope("prototype") is the same.