Map a subtree of YAML to POJO using Jackson

Question

I am using Jackson's Object mapper to map a YAML to my Pojo. My YAML is a configuration file and I want to read config of only a particular type using Jackson.

Following is how my YAML looks like:

A:
  a:
    1: i
    2: ii
    3: iii

  b:
   foo: bar

I want to read all the data lying under Aa ie 1,2,3 in a POJO.

My POJO looks like

public class MyPojo{
 String one;
 String two;
 String three;
}

You get the idea. I want to map all the children of a particular node in Pojo.

I know I can readTree("myYaml").get("A").get("a") and get list of all children. But is there any way already in Jackson to convert that subtree to Pojo just like readValue(file, class) ??

Answer 1

No one helped me so I helped my self:).

There is a method treeToValue(TreeNode, Class) , so nesting treeToValue and readTree helps in doing the desired thing.

So in order to read the subtree Aa , we need to do

File myYamlFile = new File(someclass.getClass().getClassLoader().getResource("myYAML").getFile())
MyPojo myPojo = jacksonObjectMapper.treeToValue(jacksonObjectMapper.readTree(myYamlFile).get("A").get("a"), MyPojo.class)