application.yml的格式寫法：（注意在值的前面有空格）

server:
    port: 8081
aa:
    name: 代斌
    age: 21
    list: [你好, 哈利]
    map: {a: 世界,b: 不知道}
    dog: {dog_name: 狗名字, dog_age: 89}

想要專案中可以讀取配置檔案中的資訊需要配置外掛

<dependency>
   <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-configuration-processor</artifactId
 
>
    <optional>true</optional>
</dependency>

用法

**Aa類**

package com.example.daibin.bean;


import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.stereotype.Component;

import java.util.List;
import java.util.Map;
@Component
 

@ConfigurationProperties(prefix = "aa")
public class Aa {
    private String name;
    private int age;
    private List<Object> list;
    private Map<String,Object> map;
    private Dog dog;

    @Override
    public String toString() {
        return "Aa{" +
                "name='" + name + '\''
 
 +
                ", age=" + age +
                ", list=" + list +
                ", map=" + map +
                ", dog=" + dog +
                '}';
    }

    public String getName() {
        return name;
    }

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

    public int getAge() {
        return age;
    }

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

    public List<Object> getList() {
        return list;
    }

    public void setList(List<Object> list) {
        this.list = list;
    }

    public Map<String, Object> getMap() {
        return map;
    }

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

    public Dog getDog() {
        return dog;
    }

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

    **dog類**

package com.example.daibin.bean;

public class Dog {
    private String dog_name;
    private int dog_age;

    @Override
    public String toString() {
        return "Dog{" +
                "dog_name='" + dog_name + '\'' +
                ", dog_age=" + dog_age +
                '}';
    }

    public String getDog_name() {
        return dog_name;
    }

    public void setDog_name(String dog_name) {
        this.dog_name = dog_name;
    }

    public int getDog_age() {
        return dog_age;
    }

    public void setDog_age(int dog_age) {
        this.dog_age = dog_age;
    }
}

這是輸出的結果（說明讀取配置檔案中的資訊成功）
Aa{name=’代斌’, age=21, list=[你好, 哈利], map={a=世界, b=不知道}, dog=Dog{dog_name=’狗名字’, dog_age=89}}