201671010122 2016-2017-2 "Java Programming" understanding of collections

understanding of the collection

11th Week of Java Learning is still on schedule, this week we went into the study of the collection,theJAVA collection inside a lot of content and the content of the data structure is very close, we are learning the structure of the linear structures: Linear table, Stack, Queue and non-linear structure: learning the collection of JAVA after the tree and diagram , it feels a lot easier, perhaps this is the so-called relationship between disciplines and disciplines it!

Javain the collection according toJDKversion, divided into two chunks. In theJDK1.0with the1.1the collection classes in the version are independent of each other and lack a unified set of mechanisms, mainly:Vectorclass: Similar to the variable length of the array, can only store objects, cannot hold the basic data type;Stackclass: YesVectorSubclasses of the class,Vectorclass of methods he applies, he describes the stack data structure, namely the advanced post-out linear structure;Hashtableclasses: Searching for elements by key values,Hashtableuse a special value to determine the key, namedHashcode (Hash Code). These three categories I basically have mastered the use of its methods and some considerations. In theJDK1.2version, there was a huge collection system that he used to perform various collection operations. The interfaces in the collection framework are:Collectioninterface, which is the root interface of the collection hierarchy, containsSetClasses andListclass, the implementation of these two classes interface I have a general understanding of the first;Mapinterface that contains the key-value pairs (Key-valueYes, he also has his own implementation interface, but I think this part of the content is more abstract, and mapping has an association, not very good, read aboutMapclass of the program, my understanding is not very good, there is a sense of indefinitely, but also I need to strengthen their understanding of it.

now is the time for us to review what we've learned, JAVA content is more, review must start early, teachers also provide us with a concise review of information, so my review plan also began to start gradually, the No. 456 chapter of the content of the strength is not enough, I think: now go back to see, may be much better.

201671010122 2016-2017-2 "Java Programming" understanding of collections