java - Spring 3.x - @Async methods not called concurrently by task executor - Stack Overflow

java - Spring 3.x - @Async methods not called concurrently by task executor - Stack Overflow

The issue is that you're calling the methods internally so they're not proxied. For the @Async to work you need to retrieve the object from your application context and invoke the methods on the retrieved copy. Invoking it internally will not work.

The same thing happens if you try to invoke internal @Transactional methods. See the Note: section at the end of the Spring docs explaining @Transactional for details.

Additionally, the way you're immediately calling .get() on the Future return values is incorrect. If you want them to happen in parallel you should submit all the tasks then retrieve each one via .get().

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