HealthCheckServlet

package th.in.oneauthen.servlet;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.URISyntaxException;
import java.util.Date;
import java.util.List;
import java.util.concurrent.Executors;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.TimeUnit;

import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;


import org.apache.http.HttpResponse;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.utils.URIBuilder;
import org.apache.http.impl.client.HttpClientBuilder;


import com.google.gson.Gson;


import th.in.oneauthen.object.HelpcheckDB;
import th.in.oneauthen.object.SystemConfigDB;
import th.in.oneauthen.object.DAO.HelpcheckDAO;
import th.in.oneauthen.object.DAO.SystemConfigDAO;



@WebServlet(description = "test for loadstart", urlPatterns = { "/HealthCheckServlet" },loadOnStartup = 5)
public class HealthCheckServlet extends HttpServlet {
    private static final long serialVersionUID = 1L;
    public static String RESPONSE_QUERY = "query";

    /**
     * @see HttpServlet#HttpServlet()
     */
    public HealthCheckServlet() {
        super();
        // TODO Auto-generated constructor stub
    }

    /**
     * @see Servlet#init(ServletConfig)
     */
    public void init(ServletConfig config) throws ServletException {

                Runnable runnable = new Runnable() {
                  public void run() {
                    // task to run goes here


                      query();
                      try {
                        check() ;
                    } catch (URISyntaxException | IOException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    }
                  }
                };

                ScheduledExecutorService service = Executors
                                .newSingleThreadScheduledExecutor();
                service.scheduleAtFixedRate(runnable, 0, 1, TimeUnit.MINUTES);

    }

    /**
     * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // TODO Auto-generated method stub
        response.getWriter().append("Served at: ").append(request.getContextPath());
    }

    /**
     * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // TODO Auto-generated method stub
        doGet(request, response);
    }

     public static void check() throws URISyntaxException, ClientProtocolException, IOException {
            BufferedReader br = null;
            String output;
            StringBuilder responseBuilder = null;

            HttpClient httpClient = HttpClientBuilder.create().build();
            URIBuilder uriBuilder;

            String checkURL = null;

            try {
                SystemConfigDB sysConfig = new SystemConfigDAO().find("CHECK_URL");
                if (sysConfig != null)
                    checkURL = sysConfig.getValue();

            } catch (Exception e) {
                e.printStackTrace();
            }



            int start = (int) System.currentTimeMillis();
                uriBuilder = new URIBuilder(checkURL);
                HttpGet getMethod = new HttpGet(uriBuilder.build());


                HttpResponse httpResponse = httpClient.execute(getMethod);
                int responseCode = httpResponse.getStatusLine().getStatusCode();
                int end = (int) (System.currentTimeMillis()-start);
                System.out.println(end +"ms");
                if (responseCode == 201 || responseCode == 200) {
                    br = new BufferedReader(new InputStreamReader((httpResponse.getEntity().getContent())));
                    responseBuilder = new StringBuilder();
                    while ((output = br.readLine()) != null) {
                        responseBuilder.append(output);
                    }
                    System.out.println(responseBuilder.toString());
                    System.out.println(new Date());

                    HelpcheckDAO checkDao = new HelpcheckDAO();
                    HelpcheckDB check = new HelpcheckDB();
                    check.setStatus(responseBuilder.toString());
                    check.setTimeUse(end);
                    check.setTimeNow(new Date());
                    try {
                        checkDao.save(check);
                    } catch (Exception e) {
                        e.printStackTrace();
                    }

                } else {
                    System.out.println("Failed : HTTP error code : " + httpResponse.getStatusLine().getStatusCode());
                }
            }
     public static void query() {

         HelpcheckDAO check  = new HelpcheckDAO();
         List<HelpcheckDB> listCheck = check.getList();
         RESPONSE_QUERY = new Gson().toJson(listCheck);


     }



}