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Case 1: Lambda expression exercise 1 Requirements: define an interface (Eatable), which defines an abstract method: void eat();         Define a test class (EatableDemo) and provide two methods in the test class                 One method is: use eatable (eatable E)     ...

background The thing is, at present, I am participating in the construction of XXXX project and need to interface with a third party. There are several asynchronous notifications in the other party's interface. In order to ensure the security of the interface, it is necessary to verify the parameters of the interface. In order to facilitate t ...

prefaceLast article Git Worktree Dharma is really fragrant Let's learn how git worktree helps me work in multiple branches at the same time without affecting each other. However, the directory where the worktree is created is not under the current project. I always feel that these created WorkTrees do not belong to the current project, which is ...

This article is excerpted from "design patterns should be learned this way"1 definition of specification modeSpecification Pattern can be considered as an extension of composite pattern. Many times, some conditions in the program determine the business logic. These conditions can be extracted and combined in a certain relationship (an ...

Write in front Recently, in project development, easy excel technology was used to analyze and write excel, so today I share with you how to use easy excel technology to analyze Excel files Introduction to Easyexcel Technology Easyexcel technology is developed on the basis of poi. It is the optimization and promotion of poi '. Compared with ...

concept Do you understand the database index? Generally speaking, the underlying data structure There are two common mysql structures: Hash index, B+ Tree index and full text index. We use innoDB engine, The default is B + tree. Differences between the two structures: The bottom layer of hash index is hash tab ...

This article is excerpted from "design patterns should be learned this way"1. Application scenario of intermediary modeIn real life, the existence of intermediaries is indispensable. Without intermediaries, we can't communicate with distant friends. Each colleague object will reference each other. If each object interacts with multipl ...

##Database connection pool       The code logic in the previous section is equivalent to opening a restaurant, recruiting a waiter connection to connect to the database service when the guest comes, and firing the close when the guest leaves   So we should recruit a few employees. It's a great waste of resources   &n ...

summary When communicating between our client and server, we must abide by certain protocols. These protocols may have been designed in advance, such as Http protocol, or we can customize them. Last We explained some codecs provided by Netty, so that we can design some protocols ourselves. This article mainly explains the Http protocol in Ne ...

Here are some common interview questions, analysis of test sites, answers, etc. Basic concepts Some basic java knowledge, various basic concepts, etc. What are the access modifiers? difference? Modifier Current classSame packageSubclassOther packagespublic√√√√protected√√√×default√√××private√×××    Scan VX for Java data, front-end ...