To learn Spring Framework Basics like Dependency Injection, Bean Life Cycle, Autowiring, MVC, AOP(Aspect Oriented Programming), it should take around 50+ Hrs , assuming spending about 2 to 3 hrs, in about 30 days(approximately) & it also depends on your prior expertise/experience, you will get some confidence.
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Since most of the developers want to learn Spring MVC, I suggest you first start with Spring Core and then follow the Spring MVC part.
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