Spring Boot中的嵌套外部配置类

Question

我想把我application.yml注入这样的嵌套Map:

application.yml

components:
  component1:
    host: host1
    port: 1111
  component2:
    host: host2
    port: 2222
  component3:
    host: host3
    port: 3333

MyComponents.java

@Component
@ConfigurationProperties
public class MyComponents {
  Map<String, MyComponent> components;

  public static class MyComponent {
    String host;
    Integer port;

    //empty constructor, getters, setters
  }

  //empty constructor, getters, setters
}

但即使我没有实例化object(@Autowire),我收到以下错误信息:

org.springframework.beans.NullValueInNestedPathException:bean类的无效属性'components [component1]'[package.path.MyComponents]:无法实例化属性类型[package.path.MyComponents $ MyComponent]以自动增长嵌套属性路径:java .lang.InstantiationException:package.path.MyComponents $ MyComponent

如何将配置添加到我的类布局中？

解:

我自己找到了解决方案:内部类必须是静态的.

Answer 1

内部class MyComponent必须是static：

@Component
@ConfigurationProperties
public class MyComponents {
  Map<String, MyComponent> components;

  public static class MyComponent {
    String host;
    Integer port;
    
    //empty constructor, getters, setters
  }

  //empty constructor, getters, setters
}

_{这个答案是由OP Squall在CC BY-SA 3.0下作为对Spring Boot中的嵌套外部配置类问题的编辑发布的。}