In the source code of collection system, the design of HashMap in Map is the most classic, involving data structure, programming idea, hash calculation and so on. It is necessary to refer to some ideas of source code in daily development.

A small project is going to use Google Map as its main presentation, showing the current state of the world on a map. Although I have used Google Map before, it still took me two days to complete the development of the main map function. Here is a record for my own use.

There are a lot of things that I didn't pay much attention to when I was learning. When I reviewed HashMap, I also found that there are many problems that can be studied in detail, which will eventually return to mathematics. For example, why is the loading factor of HashMap 0.75?

You've all heard of the Map interface, right? It is a common way to store key-value pairs in Java, and I believe you should also be familiar with HashMap. When it comes to HashMap, I think everyone who knows a little bit about it should say: this is a way to store key-value pairs, and it is stored in the form of array and linked list. But do you have any idea how it's actually stored and how the underlying architecture is implemented?

Steam in Java8 can be defined as a sequence of elements from a source, and Streams supports aggregation of elements, which are collections and arrays of data that feed a stream, in which we can get the data that we want from the stream

Sorting Lists (mainly ArrayList) and Maps (mainly HashMap) is the most common business scenario, so it's worth systematically reviewing and learning about them. This article summarizes the commonly used sorting methods.

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Java collection system Set (interface) : on behalf of the disorder, do not repeat collection List (interface) : on behalf of the orderly and repeated collection of Map (interface) : on behalf of a Set of mapping the Queue (interface) : Representing a Queue Collection Collection Classes and Arrays Difference An array element can be either a value of a primitive type or an object (which actually holds a reference variable to an object). Only objects can be stored in a collection (in fact, objects' reference variables are stored, but it is common practice...

What is the difference between a class and an ID selector in a CSS class? What is the difference between a class and an ID selector? What is the difference between map, reduce and filter in these three methods? [Soft Skills] How do you get along with airborne leaders? In The Analects of Confucius, Confucius Zeng said, "I examine myself three times every day." (I reflect on myself many times every day.) Front end interview daily...