traininfoservice/banedk/TimetableServlet.java

package dk.thoerup.traininfoservice.banedk;

import java.io.IOException;
import java.util.List;
import java.util.logging.Level;
import java.util.logging.Logger;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import dk.thoerup.circuitbreaker.CircuitBreakerException;
import dk.thoerup.traininfoservice.Statistics;

/**
 * Servlet implementation class 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();
                
                boolean useTempSite =  Boolean.parseBoolean( getServletContext().getInitParameter("usetempsite") );
                int cacheTimeout =  Integer.parseInt( getServletContext().getInitParameter("cache_timeout") );
                logger.info( "TimetableServlet, use temp site=" + useTempSite + ", cache=" + cacheTimeout);
                fetcher = new TimetableFetcher(useTempSite,cacheTimeout);
        }
        
        @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
                {
                        List<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");
                        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(List<TimetableBean> timetable) {
                StringBuffer sb = new StringBuffer();
                
                sb.append("<timetable>");
                
                for (TimetableBean bean : timetable) {
                        sb.append("<entry");
                        if (bean.isCurrent())
                                sb.append(" current=\"true\"");
                        sb.append(">");
                        
                        sb.append("<station>").append( bean.getStation() ).append("</station>");
                        sb.append("<arrival>").append( bean.getArrival() ).append("</arrival>");
                        sb.append("<departure>").append( bean.getDeparture() ).append("</departure>");
                        sb.append("<stationid>").append( bean.getStationId() ).append("</stationid>");
                        
                        sb.append("</entry>");
                }
                
                sb.append("</timetable>");
                
                return sb.toString();
        }

}
1	package dk.thoerup.traininfoservice.banedk;
2
3	import java.io.IOException;
4	import java.util.List;
5	import java.util.logging.Level;
6	import java.util.logging.Logger;
7
8	import javax.servlet.ServletException;
9	import javax.servlet.http.HttpServlet;
10	import javax.servlet.http.HttpServletRequest;
11	import javax.servlet.http.HttpServletResponse;
12
13	import dk.thoerup.circuitbreaker.CircuitBreakerException;
14	import dk.thoerup.traininfoservice.Statistics;
15
16	/**
17	* Servlet implementation class TimetableServlet
18	*/
19	public class TimetableServlet extends HttpServlet {
20	private static final long serialVersionUID = 1L;
21
22
23	Logger logger = Logger.getLogger( TimetableServlet.class.getName() );
24
25	TimetableFetcher fetcher;
26
27	@Override
28	public void init() throws ServletException {
29	super.init();
30
31	boolean useTempSite = Boolean.parseBoolean( getServletContext().getInitParameter("usetempsite") );
32	int cacheTimeout = Integer.parseInt( getServletContext().getInitParameter("cache_timeout") );
33	logger.info( "TimetableServlet, use temp site=" + useTempSite + ", cache=" + cacheTimeout);
34	fetcher = new TimetableFetcher(useTempSite,cacheTimeout);
35	}
36
37	@Override
38	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
39	if (request.getParameter("train") == null) {
40	response.sendError(400, "not enough parameters (train)");
41	return;
42	}
43	if (request.getParameter("type") == null) {
44	response.sendError(400, "not enough parameters (type)");
45	return;
46	}
47	Statistics.getInstance().incrementTimetableLookups();
48
49	String train = request.getParameter("train").trim();
50	String type = request.getParameter("type").trim();
51
52	try
53	{
54	List<TimetableBean> timetable = fetcher.cachedLookupTimetable(train, type);
55
56	String responseXML = formatTimetable(timetable);
57
58	response.setContentType("text/xml");
59	response.getWriter().print(responseXML);
60	} catch (java.io.IOException ioe) {
61	logger.warning("(timetable) Read failed, type=" + type + ", train="+train + ". " + ioe.getMessage());
62	Statistics.getInstance().incrementTimetableErrors();
63	response.sendError(500, "Backend timed out");
64	} catch (CircuitBreakerException cbe) {
65	logger.warning("Circuitbreaker - failing fast");
66	Statistics.getInstance().incrementTimetableErrors();
67	response.sendError(500);
68	}catch (Exception e) {
69	logger.log(Level.WARNING, "failure looking up timetable: type=" + type + ",train=" +train, e);
70	Statistics.getInstance().incrementTimetableErrors();
71	response.sendError(500);
72	}
73
74	}
75
76	String formatTimetable(List<TimetableBean> timetable) {
77	StringBuffer sb = new StringBuffer();
78
79	sb.append("<timetable>");
80
81	for (TimetableBean bean : timetable) {
82	sb.append("<entry");
83	if (bean.isCurrent())
84	sb.append(" current=\"true\"");
85	sb.append(">");
86
87	sb.append("<station>").append( bean.getStation() ).append("</station>");
88	sb.append("<arrival>").append( bean.getArrival() ).append("</arrival>");
89	sb.append("<departure>").append( bean.getDeparture() ).append("</departure>");
90	sb.append("<stationid>").append( bean.getStationId() ).append("</stationid>");
91
92	sb.append("</entry>");
93	}
94
95	sb.append("</timetable>");
96
97	return sb.toString();
98	}
99
100	}