SpringBoot2.2版本配置绑定

具体可以查看这篇：https://www.cnblogs.com/dalianpai/p/11772382.html

 原始的

/**
 * @author WGR
 * @create 2019/12/6 -- 15:14
 */
@Component
@ConfigurationProperties("person")
public class Person {
    private String lastName;
    private Integer age;
    private Boolean boss;
    private Map<String, Object> maps;
    private List<Object> lists;

    @Override
    public String toString() {
        return "Person{" +
                "lastName='" + lastName + '\'' +
                ", age=" + age +
                ", boss=" + boss +
                ", maps=" + maps +
                ", lists=" + lists +
                '}';
    }

    @Override
    public int hashCode() {

        return Objects.hash(lastName, age, boss, maps, lists);
    }

    public String getLastName() {
        return lastName;
    }

    public void setLastName(String lastName) {
        this.lastName = lastName;
    }

    public Integer getAge() {
        return age;
    }

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

    public Boolean getBoss() {
        return boss;
    }

    public void setBoss(Boolean boss) {
        this.boss = boss;
    }

    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;
    }
}

@Autowired
    Person person;

    @GetMapping("/test")
    public Person test(){
        return person;
    }

测试结果：

{"lastName":"wgr","age":20,"boss":null,"maps":null,"lists":null}

2.2.1.RELEASE

SpringBoot 2.2.1.RELEASE版本中@SpringBootApplication注解部分源码如下所示：

@Target(ElementType.TYPE)
@Retention(RetentionPolicy.RUNTIME)
@Documented
@Inherited
@SpringBootConfiguration
@EnableAutoConfiguration
@ComponentScan(excludeFilters = { @Filter(type = FilterType.CUSTOM, classes = TypeExcludeFilter.class),
        @Filter(type = FilterType.CUSTOM, classes = AutoConfigurationExcludeFilter.class) })
public @interface SpringBootApplication {
    //...
}

我们发现在SpringBoot2.2.1.RELEASE版本的@SpringBootApplication注解中已经不再默认添加@ConfigurationPropertiesScan注解的支持了，也就是我们无法通过默认的配置实现扫描@ConfigurationProperties注解的类，也无法将application.yml/application.properties文件的配置内容与实体类内的属性进行绑定。

加入@ConfigurationPropertiesScan

@ConfigurationPropertiesScan
public class Mongodb2Application {

    @Autowired(required=false)
    Person person;

    @GetMapping("/test")
    public Person test(){
        return person;
    }
}

@ConfigurationProperties( prefix = "person")
//@ConstructorBinding
//@Component
public class Person {
    private String lastName;
    private Integer age;

    public void setLastName(String lastName) {
        this.lastName = lastName;
    }

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

    @Override
    public String toString() {
        return "Person{" +
                "lastName='" + lastName + '\'' +
                ", age=" + age +
                '}';
    }

//    public Person(String lastName, Integer age) {
//        this.lastName = lastName;
//        this.age = age;
//    }

    public String getLastName() {
        return lastName;
    }

    public Integer getAge() {
        return age;
    }
}

可以不要在Person上加@Component注解了。