Enthuware

i dont get why collections are splitted in 3 chapters

16 Generics
18 Collections
21 Streams

chapter 16 starts with generics, followed by collections, ends with generics...

Collections and generics are closely linked. Chapter 16 introduces the concept of collections and the need for generics without getting bogged down with the details of the Collections API. Other than section 16.2, everything in this chapter 16 is important for the exam. Detailed discussion of generics in separated out section 16.2 so that one can simply skip this section altogether without affecting their preparation for the exam. But the details are there if one is curious to learn about them.

Chapter 18 is focused on the Collections API i.e. the classes and interfaces that are available in the Java collections framework. This is also important for the exam but to make sense of and to use them the way exam expects you to use them, you need to know about generics as well as lambdas and method references, which is why those are discussed before discussing the details of the Collections API. Collections API itself is quite huge and all of this chapter is in scope for the exam. Chapter 18 is mostly information based (stuff that you need to cram for the exam), while Chapter 16 and 17 are more logical (stuff that you need to understand).

Streams makes heavy use of collection classes and interfaces, so you cannot really avoid them while talking about streams. The streams chapter only references collections (the stuff that you learnt in previous chapters) and focuses on Streams. Again, everything in this chapter is required for the exam.

thanks a lot

so chapter 17 lambda is also more logical (stuff that you need to understand)?

cuz im reading java.util.function.Function explanation and find it very abstract

questions about lambda in OCP 17 exam will be same as in OCA 8?

what would be the difference?

Ocp 17/21 use lambdas a lot more than oca 8 in code given in the questions.

ok gotchu cuz oca 8 was like 1 question about it