YamlConstructor.java

package com.github.tuserver.api.configuration.file;

import java.util.LinkedHashMap;
import java.util.Map;

import org.yaml.snakeyaml.constructor.SafeConstructor;
import org.yaml.snakeyaml.error.YAMLException;
import org.yaml.snakeyaml.nodes.Node;
import org.yaml.snakeyaml.nodes.Tag;

import com.github.tuserver.api.configuration.serialization.ConfigurationSerialization;

public class YamlConstructor extends SafeConstructor {

	public YamlConstructor() {
		this.yamlConstructors.put(Tag.MAP, new ConstructCustomObject());
	}

	private class ConstructCustomObject extends ConstructYamlMap {
		@Override
		public Object construct(Node node) {
			if (node.isTwoStepsConstruction()) {
				throw new YAMLException("Unexpected referential mapping structure. Node: " + node);
			}

			Map<?, ?> raw = (Map<?, ?>) super.construct(node);

			if (raw.containsKey(ConfigurationSerialization.SERIALIZED_TYPE_KEY)) {
				Map<String, Object> typed = new LinkedHashMap<String, Object>(raw.size());
				for (Map.Entry<?, ?> entry : raw.entrySet()) {
					typed.put(entry.getKey().toString(), entry.getValue());
				}

				try {
					return ConfigurationSerialization.deserializeObject(typed);
				} catch (IllegalArgumentException ex) {
					throw new YAMLException("Could not deserialize object", ex);
				}
			}

			return raw;
		}

		@Override
		public void construct2ndStep(Node node, Object object) {
			throw new YAMLException("Unexpected referential mapping structure. Node: " + node);
		}
	}
}