snakeyaml命名约定

Question

From what I've seen it looks like the recommendation on yaml naming conventions is to follow the software convention, so in my case Java.

I've been given a yaml file with the following syntax

PERSON:
  NAME: John Doe

I can't get snakeyaml to map correctly to my Person object unless I change from PERSON to person. I've also tried with other variable names but only camel case or lower case object names seem to work. I can read in the all caps attribute NAME without any issues as a String when I change from PERSON to person. Can someone explain why this is the case?

public class Configuration {

  private Person person;

  public Configuration() {
    person = new Person();
  }

  public Person getPerson() {
    return person;
  }

  public void setPerson(Person person) {
    this.person = person;
  }

}

When I capitalize PERSON in the yaml file no matter the syntax of my getter/setter I can't get snakeyaml to load it. I've tried getPERSON/setPERSON with my instance variable as PERSON, but it doesn't work unless I change to person in the yaml file.

Answer 1

You need to have fields name as present in yaml file because snakeyaml internally uses Reflection Api

So your class looks like this-

 class Configuration {

    public Person PERSON;

    public Person getPERSON() {
        return PERSON;
    }

    public void setPERSON(Person PERSON) {
        this.PERSON = PERSON;
    }
}

class Person {

    public String NAME;

    public String getNAME() {
        return NAME;
    }

    public void setNAME(String NAME) {
        this.NAME = NAME;
    }
}

Note that fields need to be public as stated here

Then you need to pass the Constructor class object with the parameter as your root class.

Yaml yaml = new Yaml(new Constructor(Configuration.class));

Full code..

class Test {

    public static void main(String[] args) throws FileNotFoundException {
        String filePath = "path/to/configuartion/file/configuration.yaml";
        InputStream input = new FileInputStream(new File(filePath));
        Yaml yaml = new Yaml(new Constructor(Configuration.class));
        Configuration configuration = yaml.load(input);
    }
}