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Top 5 Books and Courses to Crack Oracle's Java SE 11 Certification | OCAJP 11 1Z0-815 and OCPJP 11 1Z0-816, 1Z0-817

Hello guys, if you are preparing for the OCAJP 11 (1Z0-815)  or OCPJP 11 (1z0-816) exam and looking for some advice on preparation then you have come to the right place. The Java SE 11 Certification is one of the toughest of Java certification at the developer level. It's much harder than OCAJP 8, it's predecessor, and some of the programmers who have attempted it calling it even harder than the professional-level certification like OCPJP 8. In order to crack Java SE 11 certification, you need to prepare hard, but, at the same time, you also need to know which areas you should focus on. What topics should you spend more time on and which books and courses can help you to learn those essential topics?

Difference between @Component, @Service, @Controller, and @Repository in Spring

Before you learn the difference between @Component, @Service, @Controller, and @Repository annotations in the Spring framework, it's important to understand the role of @Component annotation in Spring. During the initial release of Spring, all beans are used to be declared in an XML file. For a large project, this quickly becomes a massive task, and Spring guys recognize the problem rather quickly. In later versions, they provide annotation-based dependency injection and Java-based configuration. From Spring 2.5 annotation-based dependency injection was introduced, which automatically scans and registers classes as Spring bean which is annotated using @Component annotation.