How to construct Map with values in application.yml file-CodePudding

How to construct map with values in application.yml file, I was able to create a list of Objects but I'm looking for how can I construct Map

Here is my application.ymal file

parentkey:
  child:
    - key1: 123
      key2:
        subkey: value1
      key3:
        subkey1: value2
        subkey3: value3
      key4:
        subkey4: value4
    - key1: 123
      key2:
        subkey: value5
      key3:
        subkey1: value6
        subkey3: value7
      key4:
        subkey4: value8

and I created my like this:

@Configuration
@ConfigurationProperties("parentkey")
public class ConfigurationTest {
 private List<Configuration> child;
}

now in my ConfigurationTest class can I get Map with key as value of key1 and value as Object contains key2 to ke4

if yes, how Can I construct my application.ymal file

CodePudding user response：

The map in yml can be created like this

parentkey:
 child:
   123:
    key2:
     subkey: value1
    key3:
     subkey1: value2
     subkey3: value3
    key4:
     subkey4: value4
   234:
    key2:
     subkey: value5
    key3:
     subkey1: value6
     subkey3: value7
    key4:
     subkey4: value8

This can be read the same way Map<String, Object> child where keys will be 123 and 234.

CodePudding user response：

Spring can translate YAML into a variety of object types, including user-defined classes as well as things like List<> and Map<>. It is also recursive; it can translate nested objects into other types.

Knowing that, you can define an @ConfigurationProperties class that contains a Map<> and Spring will automatically create the objects to populate your map as long as it can figure out how to translate the key and value types.

For example, using a properties class like this:

@Component
@ConfigurationProperties(prefix = "parentkey")
public class MyConfigProps {
    private Map<String, String> children;

    // getters and setters
}

This YAML will populate an instance of that class:

parentkey:
  children:
    - key1: 123
    - key2: abc

In the question it looks like the children nodes are not all of the same type; some are simple integer or string values, some have nested children themselves. So you'll have to tweak my example to match the actual structure you need to support. But since Spring can translate arbitrarily nested structures/objects, almost anything is possible.