Hands-On High Performance with Spring 5

DI pitfalls

As we know, there are three DI patterns in the Spring application: constructor-setter-and field-based. Each type has different advantages and disadvantages. Only field-based DI is an incorrect approach and not even recommended by Spring.

Following is an example of a field-based injection:

@Autowiredprivate ABean aBean;

As per Spring bean best practices, we should not use field-based dependency in our Spring application. The main reason is that it is impossible to test without Spring context. As we cannot supply the dependency from outside, it will not be possible to instantiate the object independently. As per my opinion, this is the only problem with field-based injections.

As we learned in an earlier section, constructor-based ...