230115_50_SpringBoot入门

• 如果类中属性比较多，通过@value赋值比较麻烦。可以通过yaml配置文件给实例赋值。

• 新建Person类，通过@ConfigurationProperties注解可以实现配置文件注入，其中prefix可以指定注入哪个配置。

• @ConfigurationProperties作用：
  将配置文件中配置的每一个属性的值，映射到这个组件中；
  告诉SpringBoot将本类中的所有属性和配置文件中相关的配置进行绑定
  参数 prefix = “person” : 将配置文件中的person下面的所有属性一一对应
  

package com.bill;

import com.bill.Dog;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.stereotype.Component;

import java.util.Date;
import java.util.List;
import java.util.Map;

/**
 * @Auther: wangchunwen
 * @Date: 2023/1/14 - 01 - 14 - 21:10
 * @Description: com.bill.controller
 * @version: 1.0
 */
@Component
@ConfigurationProperties(prefix = "person")
public class Person {
    private String name;
    private Integer age;
    private Boolean happy;
    private Date birth;
    private Map<String,Object> maps;
    private List<Object> lists;
    private Dog dog;

    public Person(){

    }

    public Person(String name, Integer age, Boolean happy, Date birth, Map<String, Object> maps, List<Object> lists, Dog dog) {
        this.name = name;
        this.age = age;
        this.happy = happy;
        this.birth = birth;
        this.maps = maps;
        this.lists = lists;
        this.dog = dog;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public Integer getAge() {
        return age;
    }

    public void setAge(Integer age) {
        this.age = age;
    }

    public Boolean getHappy() {
        return happy;
    }

    public void setHappy(Boolean happy) {
        this.happy = happy;
    }

    public Date getBirth() {
        return birth;
    }

    public void setBirth(Date birth) {
        this.birth = birth;
    }

    public Map<String, Object> getMaps() {
        return maps;
    }

    public void setMaps(Map<String, Object> maps) {
        this.maps = maps;
    }

    public List<Object> getLists() {
        return lists;
    }

    public void setLists(List<Object> lists) {
        this.lists = lists;
    }

    public Dog getDog() {
        return dog;
    }

    public void setDog(Dog dog) {
        this.dog = dog;
    }

    @Override
    public String toString() {
        return "Person{" +
                "name='" + name + '\'' +
                ", age=" + age +
                ", happy=" + happy +
                ", birth=" + birth +
                ", maps=" + maps +
                ", lists=" + lists +
                ", dog=" + dog +
                '}';
    }
}

• person实体类对应的配置类

person:
  name: bill
  age: 4
  happy: true
  birth: 2023/01/15
  maps: {k1: v1,k2: v2}
  lists:
    - cat
    - dog
    - fish
  dog:
    name: jack
    age: 2

• 测试类

package com.bill;

import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;

@SpringBootTest
class SpringbootApplicationTests {

   @Autowired
   private Person person;

   @Test
   void contextLoads() {
      System.out.println(person);
   }

}

测试结果：