traininfoservice/banedk/TimetableServlet.java

package dk.thoerup.traininfoservice.banedk;

import java.io.IOException;
import java.io.StringWriter;

import java.util.logging.Level;
import java.util.logging.Logger;

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.simpleframework.xml.Serializer;
import org.simpleframework.xml.core.Persister;

import dk.thoerup.android.traininfo.common.TimetableBean;
import dk.thoerup.circuitbreaker.CircuitBreakerException;
import dk.thoerup.traininfoservice.Statistics;
import dk.thoerup.traininfoservice.TraininfoSettings;;

/**
 * Servlet implementation class TimetableServlet
 */
@WebServlet(urlPatterns={"/TimetableServlet"})
public class TimetableServlet extends HttpServlet {
        private static final long serialVersionUID = 1L;
       
        
        Logger logger = Logger.getLogger( TimetableServlet.class.getName() );
        
        TimetableFetcher fetcher;
        
        
        @Override
        public void init() throws ServletException {
                super.init();
                

                TraininfoSettings settings = (TraininfoSettings) getServletContext().getAttribute("settings");
                fetcher = new TimetableFetcher(settings);
        }
        
        @Override
        protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
                if (request.getParameter("train") == null) {
                        response.sendError(400, "not enough parameters (train)");
                        return;
                }
                if (request.getParameter("type") == null) {
                        response.sendError(400, "not enough parameters (type)");
                        return;
                }
                Statistics.getInstance().incrementTimetableLookups();
                
                String train = request.getParameter("train").trim();
                String type = request.getParameter("type").trim();
                                
                try
                {
                        TimetableBean timetable = fetcher.cachedLookupTimetable(train, type);
                
                        String responseXML = formatTimetable(timetable);
                
                        response.setContentType("text/xml");
                        response.getWriter().print(responseXML);
                } catch (java.io.IOException ioe) {
                        logger.warning("(timetable) Read failed, type=" + type + ", train="+train + ". " + ioe.getMessage());
                        Statistics.getInstance().incrementTimetableErrors();
                        response.sendError(500, "Backend timed out");
                } catch (CircuitBreakerException cbe) {
                        logger.warning("Circuitbreaker - failing fast, type=" + type + ", train="+train);
                        Statistics.getInstance().incrementTimetableErrors();
                        response.sendError(500);
                }catch (Exception e) {
                        logger.log(Level.WARNING, "failure looking up timetable: type=" + type + ",train=" +train, e);
                        Statistics.getInstance().incrementTimetableErrors();
                        response.sendError(500);
                }
                
        }
        
        String formatTimetable(TimetableBean timetable) throws ServletException {
                Serializer serializer = new Persister();

                StringWriter out = new StringWriter();

                try {
                        serializer.write(timetable, out);
                } catch (Exception e) {
                        throw new ServletException(e);
                }
                
                return out.toString();
        }

}
1	package dk.thoerup.traininfoservice.banedk;
2
3	import java.io.IOException;
4	import java.io.StringWriter;
5
6	import java.util.logging.Level;
7	import java.util.logging.Logger;
8
9	import javax.servlet.ServletException;
10	import javax.servlet.annotation.WebServlet;
11	import javax.servlet.http.HttpServlet;
12	import javax.servlet.http.HttpServletRequest;
13	import javax.servlet.http.HttpServletResponse;
14
15	import org.simpleframework.xml.Serializer;
16	import org.simpleframework.xml.core.Persister;
17
18	import dk.thoerup.android.traininfo.common.TimetableBean;
19	import dk.thoerup.circuitbreaker.CircuitBreakerException;
20	import dk.thoerup.traininfoservice.Statistics;
21	import dk.thoerup.traininfoservice.TraininfoSettings;;
22
23	/**
24	* Servlet implementation class TimetableServlet
25	*/
26	@WebServlet(urlPatterns={"/TimetableServlet"})
27	public class TimetableServlet extends HttpServlet {
28	private static final long serialVersionUID = 1L;
29
30
31	Logger logger = Logger.getLogger( TimetableServlet.class.getName() );
32
33	TimetableFetcher fetcher;
34
35
36	@Override
37	public void init() throws ServletException {
38	super.init();
39
40
41	TraininfoSettings settings = (TraininfoSettings) getServletContext().getAttribute("settings");
42	fetcher = new TimetableFetcher(settings);
43	}
44
45	@Override
46	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
47	if (request.getParameter("train") == null) {
48	response.sendError(400, "not enough parameters (train)");
49	return;
50	}
51	if (request.getParameter("type") == null) {
52	response.sendError(400, "not enough parameters (type)");
53	return;
54	}
55	Statistics.getInstance().incrementTimetableLookups();
56
57	String train = request.getParameter("train").trim();
58	String type = request.getParameter("type").trim();
59
60	try
61	{
62	TimetableBean timetable = fetcher.cachedLookupTimetable(train, type);
63
64	String responseXML = formatTimetable(timetable);
65
66	response.setContentType("text/xml");
67	response.getWriter().print(responseXML);
68	} catch (java.io.IOException ioe) {
69	logger.warning("(timetable) Read failed, type=" + type + ", train="+train + ". " + ioe.getMessage());
70	Statistics.getInstance().incrementTimetableErrors();
71	response.sendError(500, "Backend timed out");
72	} catch (CircuitBreakerException cbe) {
73	logger.warning("Circuitbreaker - failing fast, type=" + type + ", train="+train);
74	Statistics.getInstance().incrementTimetableErrors();
75	response.sendError(500);
76	}catch (Exception e) {
77	logger.log(Level.WARNING, "failure looking up timetable: type=" + type + ",train=" +train, e);
78	Statistics.getInstance().incrementTimetableErrors();
79	response.sendError(500);
80	}
81
82	}
83
84	String formatTimetable(TimetableBean timetable) throws ServletException {
85	Serializer serializer = new Persister();
86
87	StringWriter out = new StringWriter();
88
89	try {
90	serializer.write(timetable, out);
91	} catch (Exception e) {
92	throw new ServletException(e);
93	}
94
95	return out.toString();
96	}
97
98	}