Parsing a YAML document with a map at the root using snakeYaml

Question

I want to read a YAML document to a map of custom objects (instead of maps, which snakeYaml does by default). So this:

19:
  typeID: 2
  limit: 300
20:
  typ         


        

Answer 1

Here is what I did for a very similar situation. I just tabbed my whole yml file over one tab and added a map: tag to the top. So for your case it would be.

map:
  19:
    typeID: 2
    limit: 300
  20:
    typeID: 8
    limit: 100

And then create a static class in your class that reads this file like follows.

static class Items {
    public Map map;
}

And then to read your map just use.

Yaml yaml = new Yaml(new Constructor(Items));
Items items = (Items) yaml.load();
Map itemMap = items.map;

UPDATE:

If you don't want to or cannot edit your yml file you could just do the above transform in code while reading the file with something like this.

try (BufferedReader br = new BufferedReader(new FileReader(new File("example.yml")))) {
    StringBuilder builder = new StringBuilder("map:\n");
    String line;
    while ((line = br.readLine()) != null) {
        builder.append("    ").append(line).append("\n");
    }

    Yaml yaml = new Yaml(new Constructor(Items));
    Items items = (Items) yaml.load(builder.toString());
    Map itemMap = items.map;
}