Memcache.putIfUntouched

gistfile1.txt

package org.sinmetal.controller;

import javax.servlet.http.HttpServletResponse;

import org.slim3.controller.Navigation;
import org.slim3.controller.SimpleController;

import com.google.appengine.api.memcache.MemcacheService;
import com.google.appengine.api.memcache.MemcacheService.IdentifiableValue;
import com.google.appengine.api.memcache.MemcacheServiceFactory;

public class MemcacheController extends SimpleController {

	MemcacheService service = MemcacheServiceFactory.getMemcacheService();
	
	final String KEY = "hogeKey";
	
	@Override
	protected Navigation run() throws Exception {
		if ("POST".equals(request.getMethod().toUpperCase())) {
			if (service.contains(KEY) == false) {
				service.put(KEY, 1);
				
				response.setStatus(HttpServletResponse.SC_CREATED);
				return null;
			}
		} else if ("PUT".equals(request.getMethod().toUpperCase())) {
			IdentifiableValue identifiable = service.getIdentifiable(KEY);
			if (identifiable == null) {
				response.sendError(HttpServletResponse.SC_NOT_FOUND);
				return null;
			}
			
			int value = Integer.parseInt(identifiable.getValue().toString());
			value++;
			boolean result = service.putIfUntouched(KEY, identifiable, value);
			if (result) {
				response.setStatus(HttpServletResponse.SC_OK);
				return null;
			} else {
				response.sendError(HttpServletResponse.SC_CONFLICT);
				return null;
			}
		} else if ("GET".equals(request.getMethod().toUpperCase())) {
			Object value = service.get(KEY);
			if (value == null) {
				response.sendError(HttpServletResponse.SC_NOT_FOUND);
				return null;
			} else {
				response.setStatus(HttpServletResponse.SC_OK);
				response.setContentType("text/plain");
				response.getWriter().write(value.toString());
				response.flushBuffer();
				return null;
			}
		}
		
		return null;
	}

}