SpringBoot中用Junit测试实体类中绑定yml中的值

1、编写SpringBoot的引导类

package springboot_test.springboot_test;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.context.properties.EnableConfigurationProperties;

@SpringBootApplication
public class SpringbootTestApplication {

    public static void main(String[] args) {
        SpringApplication.run(SpringbootTestApplication.class, args);
    }

}

2、编写普通实体Dog

package springboot_test.springboot_test.bean;

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

//普通实体，会做为Person类中的属性使用，不需要加任何注解
//@ConfigurationProperties(prefix = "person.dog")
//@Component
public class Dog {
    private String name;
    private String color;

    public String getName() {
        return name;
    }

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

    public String getColor() {
        return color;
    }

    public void setColor(String color) {
        this.color = color;
    }

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

3、编写需要绑定yml文件中的值的配置类Person

package springboot_test.springboot_test.bean;

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

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

//prefix指定使用yml配置文件中的哪部分开头的数据
@ConfigurationProperties(prefix = "person")
//该类也做为组件才能使用容器中的其他组件，即才能使用@ConfigurationProperties
@Component
public class Person {
    private String name;
    private String age;
    private Date birthDay;

    private Map map;
    private List list;
    //类中含有其他类的对象，想让dog在yml编写的时候也给提示，需要加上该属性
    @NestedConfigurationProperty
    private Dog dog;

    public String getName() {
        return name;
    }

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

    public String getAge() {
        return age;
    }

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

    public Date getBirthDay() {
        return birthDay;
    }

    public void setBirthDay(Date birthDay) {
        this.birthDay = birthDay;
    }

    public Map getMap() {
        return map;
    }

    public void setMap(Map map) {
        this.map = map;
    }

    public List getList() {
        return list;
    }

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

    public Dog getDog() {
        return dog;
    }

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

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

4、配置pom.xml文件

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <!--依赖的父项目，父项目中还会依赖其他父项目来决定使用的jar包的版本-->
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.2.1.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>springboot_test</groupId>
    <artifactId>springboot_test</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>springboot_test</name>
    <description>Demo project for Spring Boot</description>

    <properties>
        <java.version>1.8</java.version>
    </properties>
    <!--用于引进springmvc等相关jar包，可通过页面访问-->
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <!--用于junit测试-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>

        <!--用于热部署-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
        </dependency>

        <!--配置处理器，当类上加@ConfigurationProperties注解时，需要配置-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-configuration-processor</artifactId>
            <optional>true</optional>
        </dependency>
    </dependencies>

    <!--用于使用maven的package功能进行打包-->
    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

5、编写application.yml文件

person:
  name: zhangsan
  age: 18
  birth-day: 2019/11/19
  map: {k1: v1,k2: v2}
  list:
    - pig
    - cat
  dog:
    color: black
    name: 小狗

6、编写PersonTest.java测试类

import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;
import springboot_test.springboot_test.SpringbootTestApplication;
import springboot_test.springboot_test.bean.Person;

@SpringBootTest(classes = SpringbootTestApplication.class)
@RunWith(SpringRunner.class)
public class PersonTest {
    @Autowired
    private Person person;

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

另外在测试的时候出现了报错java.lang.Exception: No runnable methods，原因为@Test注解引入的类不对，应该引入org.junit.Test;
还有一个可能的原因是没有在方法上写@Test注解

另外，如果绑定的值是在application.properties中配置的，而不是在yml中配置的，则会出现打印结果中文乱码的问题，application.properties配置如下：

person.name=张三
person.age=18
person.birth-day= 2019/11/19
person.list=a,b,c
person.map.k1=v1
person.map.k2=v2
person.dog.name=小狗
person.dog.color=black

可通过如下所示

如有理解不到位的地方，望指教！