SpringBoot 配置文件给实体注入值方式

# 例如修改端口号 直接赋值
server.port=8888

# 例如修改端口号
server:
    port: 8888

// 实体类
@Component // 把实体类放入到spring容器中
@ConfigurationProperties(prefix = "student") // 识别配置文件
public class Student {
    private String name;
    private int age;
    private boolean sex;
    private Date birthday;
    private Map<String, Object> location;
    private String[] hobbies;
    private List<String> skills;
    private Pet pet;
    
    // .... set/get/toString
}

# yml 配置文件
student: 
	name: zs
	age: 23
	sex: true
	birthday: 2020/10/1
	location: {province: 湖北,city: 武汉, zone: 洪山}
	hobbies: [足球, 篮球]
	skills: [编程, 金融]
	pet: 
		nickName: wc
		strain: hsq

# map类型和对象类型 的两种写法
# 1.行内写法
location: {province: 湖北,city: 武汉, zone: 洪山}
pet: {nickName: wc, strain: hsq}
# 2.分行写
location:
	province: 湖北
	city: 武汉
	zone: 洪山
pet: 
	nickName: wc
	strain: hsq

# 数组、list、set
# 1、行内写法, 其中中括号还可以省略
hobbies: [足球, 篮球]
skills: [编程, 金融]
# 2、分行写
hobbies:
	- 足球
	- 篮球
skills: 
	- 编程
	- 金融

    @Autowired
    Student student;
    @Test
    void contextLoads() {
        System.out.println(student);
    }

# 如果对字符串加单引号，双引号会有什么区别
location: {province: "湖北",city: '武汉', zone: 洪山}
# 如果引号中只是字符串时没什么区别
location: {province: "湖\n北",city: '武\n汉', zone: 洪\n山}
# 此时双引号中的转义字符会被识别，会换行，单引号和不加引号会原样输出

student.name=ls
student.age=24
...

@PropertySource(value = {"classpath:conf.properties"})
public class Student {
    ...

person:
  lastName: Mary
  age: 16
  birthDate: 2004/01/01
  maps: {one:1,two:2,three:3}
  lists:
    - 1
    - 2
    - 3
  pet:
    name: wanGCai
    age: 3

@Component
@ConfigurationProperties(prefix = "person")
public class Person {
    private String lastName;
    private Integer age;
    private Date birthDate;
    private Map<String,Object> maps;
    private List<Object> lists;
    private Pet pet;
    //省略get，set方法
    @Override
    public String toString() {
        String mapValue = "";
        
        if(this.maps!=null){
            for(String key:this.maps.keySet()){
                Object value = this.maps.get(key);
                mapValue += key+"\t"+value+"\t";
            }
        }
        return "lastName:"+this.lastName+
                "\nage:"+this.age+
                "\nbirthDate:"+this.birthDate+
                "\nmaps:"+mapValue+
                "\nlists:"+this.lists+
                this.pet;
    }
}

public class Pet {
    private String name;
    private Integer age;
    //省略get，set方法
    
    @Override
    public String toString() {
        return "\nPet:\n\tPet name:"+this.name+
                "\n\tPet age:"+this.age+"\n";
    }
}

<!--导入配置文件处理器，配置文件进行绑定就会有提示-->
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-configuration-processor</artifactId>
    <optional>true</optional>
</dependency>

@SpringBootTest
class DemoApplicationTests {
    @Autowired
    Person person;
    @Test
    void contextLoads() {
        System.out.println(person.toString());
    }
}

 <bean class="Person">
     <property name="lastName" value="字面量/${key}从环境变量、配置文件中获取值/#{SpEL}"></property>
 <bean/>

@Component
public class Person {
    @Value("${person.last-name}")  //@Value("#{'Lily'.toUpperCase()}")
    private String lastName;
    @Value("#{11*2}")
    private Integer age;
    private Date birthDate;
    private Map<String,Object> maps;
    private List<Object> lists;
    private Pet pet;    
    //省略get,set和toString    
}

person.lastName = Lily
person.age = 20
person.birthDate = 2000/01/01
person.maps.one = 1
person.maps.two = 2
person.lists = a,b,ch
person.pet.name = wangcai
person.pet.age = 3

@Component
@PropertySource(value = {"classpath:person.properties"})
@ConfigurationProperties(prefix = "person")
public class Person {
    //...省略属性，get,set,toString
}

@Component
@PropertySource(value = {"classpath:person.properties"})
public class Person {    
    @Value("${person.last-name}")
    private String lastName;    
    //...省略属性，get,set,toString
}