JsonVerification.java

package quadrum.lib;

import java.io.File;
import java.lang.reflect.Field;
import java.util.List;
import java.util.Map;

import com.google.common.collect.Lists;
import com.google.gson.JsonElement;
import com.google.gson.JsonObject;
import com.google.gson.annotations.SerializedName;

import org.apache.logging.log4j.Level;

import quadrum.Quadrum;

public class JsonVerification {

	private static final String ERROR = "Failed to load %s. One or more required fields were missing %s";

	public static boolean verifyRequirements(File file, JsonObject jsonObject, Class<?> clazz) {
		List<String> keys = Lists.newArrayList();
		for (Map.Entry<String, JsonElement> entry : jsonObject.entrySet())
			keys.add(entry.getKey());

		List<String> missingFields = Lists.newArrayList();

		for (Field field : clazz.getDeclaredFields()) {
			String name = field.getName();
			if (field.getAnnotation(SerializedName.class) != null)
				name = field.getAnnotation(SerializedName.class).value();

			if (field.getAnnotation(Required.class) != null && !keys.contains(name))
				missingFields.add(name);
		}

		if (!missingFields.isEmpty()) {
			Quadrum.log(Level.WARN, ERROR, file.getName(), missingFields);
			return false;
		} else
			return true;
	}
}