SpringBoot 注入配置报错“The elements w

SpringBoot 注入配置报错“The elements were left unbound

SpringBoot2.4 注入自定义注解配置，nacos配置中心拉取配置报错 The elements [sh.dn.persons[0].age,sh.dn.persons[0].name,sh.dn.persons[1].age,sh.dn.persons[1].name] were left unbound.

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自定义配置

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import lombok.Data;
import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.stereotype.Component;

import java.util.List;


@ConfigurationProperties(prefix = "sh.dn")
@Component
@Data
@ConditionalOnProperty(value = "sh.dn.enable", havingValue = "true", matchIfMissing = false)
public class RIdConfig {

    private Boolean enable;
    private String test;
    private List<Person> persons;

}


public class Person {
  private String name;
  private Integer age;
}

Person类

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nacos配置中心配置，没有问题

sh:
  dn:
    enable: true
    test: test_jz
    persons:
    - age: 19
      name: 张三
    - age: 20
      name: 李四

问题原因

Person类中使用了lombok来生成get、set方法，缺少无参数的构造器，所以SpringBoot 启动无法创建对象，导致无法正常注入配置值

fix方案

添加lombok注解，生成无参构造器即可

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@NoArgsConstructor
@Data
public class Person {
  private String name;
  private Integer age;
}

参考
https://stackoverflow.com/questions/56637271/reason-the-elements-were-left-unbound
https://blog.csdn.net/cnds123321/article/details/118117356