SpringBoot Metadata generated by the configuration properties annotation processor can miss inherited properties from nested classes

Some properties of 3rd party provided class with inheritance relationship cannot be render to configuration metadata.

Versions

• Spring Boot 2.3.0.RELEASE

Details

For example, following class provides from 3rd-party library:

Example 1

public class BaseConfig {
  private boolean boolValue;
  private int intValue;
  private final Nest nest = new Nest();
  // getter and setter ...
}

public class ChildConfig extends BaseConfig {
  private long longValue;
  private final NestInChild childNest = new NestInChild();
  // getter and setter ...
  public static class NestInChild {
    private boolean boolValue;
    private int intValue;
    // getter and setter ...
  }
}

  @Bean
  @ConfigurationProperties(prefix = "my.child")
  public ChildConfig childConfig() {
    return new ChildConfig();
  }

Above configuration is valid and bind to all properties but the spring-boot-configuration-processor cannot render the metadata of the BaseConfig#nest property (nested property on parent class).

Example 2

public class OverrideChildConfig extends BaseConfig {
  private long longValue;
  private final CustomNest nest = new CustomNest();
  @Override
  public CustomNest getNest() { // override getter as return the custom nested object
    return nest;
  }
  // getter and setter ...

  public static class CustomNest extends Nest { // custom class of nested class defined in parent class
    private long longValue;
    // getter and setter ...
  }
}

  @Bean
  @ConfigurationProperties(prefix = "my.override-child")
  public OverrideChildConfig overrideChildConfig() {
    return new OverrideChildConfig();
  }

Above configuration is valid and bind to all properties but the spring-boot-configuration-processor cannot render the metadata of the OverrideChildConfig#nest property.

Executable examples

• https://github.com/kazuki43zoo/spring-boot-issue-21626

Comment From: kazuki43zoo

I've published the executable example.

Comment From: philwebb

We might be able to refine PropertyDescriptor.isParentTheSame to detect these types. Processing complicated class relationships with the annotation processor is unfortunately quite difficult.

Comment From: kazuki43zoo

@philwebb

Thanks for your quick response !! I found a workaround as follow:

For Example1

public class SpringBootChildConfig extends ChildConfig {
  @ConfigurationProperties("my.child.nest") // mark nested configuration property on sub class
  @Override
  public Nest getNest() {
    return super.getNest();
  }
  @ConfigurationProperties("my.child.child-nest")  // mark nested configuration property on sub class
  @Override
  public ChildNest getChildNest() {
    return super.getChildNest();
  }
}

For Example2

public class SpringBootOverrideChildConfig extends OverrideChildConfig {
  @ConfigurationProperties("my.override-child.nest")  // mark nested configuration property on sub class
  @Override
  public CustomNest getNest() { // override getter as return the custom nested object
    return super.getNest();
  }
}