package foundation.state.approve;

import foundation.dao.preload.Bucket;
import foundation.state.StateMachineLoader;

public class ApproveTemplateBucket extends Bucket<ApproveTemplate> {
	
	private static ApproveTemplateBucket instance;
	
	private ApproveTemplateBucket() {

	}
	
	public static synchronized ApproveTemplateBucket getInstance() {
		if (instance == null) {
			instance = new ApproveTemplateBucket();
		}
		
		return instance;
	}

	public ApproveTemplate getOrLoad(String templateId) throws Exception {
		ApproveTemplate result = get(templateId);
		
		if (result != null) {
			return result;
		}
		
		synchronized (this) {
			result = get(templateId);
			
			if (result != null) {
				return result;
			}
			
			result = StateMachineLoader.loadOneApproveTemplate(templateId);
			
			if (result != null) {
				loadOne(templateId, result);
			}
		}
		
		return result;
	}

}