How to use spring easily

Today, I will talk to you about how to use spring easily. Many people may not know much about it. In order to make you understand better, the editor has summarized the following contents for you. I hope you can get something according to this article.

The following is suitable for students who have just started spring. Let's talk about the simple use of spring.

First create a maven project and import spring's jar 4.0.0 org.example spring-demo 1.0-SNAPSHOT org.springframework spring-context 5.2.8.RELEASE junit junit 4.12 to create an entity class Userpublic class User {private Integer id; private String username Private String password; public Integer getId () {return id;} public void setId (Integer id) {this.id = id;} public String getUsername () {return username;} public void setUsername (String username) {this.username = username;} public String getPassword () {return password;} public void setPassword (String password) {this.password = password }} create Dao interface and simple implementation

UserDao interface with an add method and a method to get user through id

Public interface UserDao {void addUser (User user); User getUser (Integer id);}

Interface, our goal is to use spring, so we don't call the database directly.

Public class UserDaoImpl implements UserDao {private final List user = new ArrayList (); @ Override public void addUser (User user) {this.user.add (user); System.out.println ("added successfully");} @ Override public User getUser (Integer id) {List collect = user.stream (). Filter (w-> w.getId (). Equals (id)) .requests (Collectors.toList ()); if (collect.size ())