package frame.data.meta;

import java.util.HashMap;
import java.util.Map;

public class MetaContainer {

	private static MetaContainer instance;
	private Map<String, EntityMeta> metaMap;
	
	
	private MetaContainer() {
		metaMap = new HashMap<String, EntityMeta>();
	}
	
	public static synchronized MetaContainer getInstance() {
		if (instance == null) {
			instance = new MetaContainer();
		}
		
		return instance;
	}
	
	public static EntityMeta get(String entityName) throws Exception {
		return instance.doGet(entityName, false);
	}
	
	public static EntityMeta get(String entityName, boolean refresh) throws Exception {
		return instance.doGet(entityName, refresh);
	}

	public EntityMeta doGet(String tableName, boolean refresh) throws Exception {
		if (tableName == null) {
			return null;
		}
		
		tableName = tableName.toLowerCase();
		
		EntityMeta meta = metaMap.get(tableName);
		
		if (refresh || meta == null) {
			MetaDataLoader metaDataLoader = new MetaDataLoader(tableName);
			EntityMeta newMeta = metaDataLoader.getEntityMeta();
			
			metaMap.put(tableName.toLowerCase(), newMeta);
			meta = newMeta;
		}
		
		return meta;
	}

}