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 || request.getParameter("train").equals("") ) {
                        response.sendError(400, "not enough parameters (train)");
                        return;
                }
                if (request.getParameter("type") == null || request.getParameter("type").equals("") ) {
                        response.sendError(400, "not enough parameters (type)");
                        return;
                }
                Statistics.getInstance().incrementTimetableLookups();
                
                String train = request.getParameter("train").trim();
                String type = request.getParameter("type").trim();
                        
                
                TimetableBean timetable = null;
                try
                {
                        timetable = fetcher.cachedLookupTimetable(train, type);
                
                } catch (java.io.IOException ioe) {
                        logger.warning("(timetable) Read failed, type=" + type + ", train="+train + ". " + ioe.getMessage());
                        Statistics.getInstance().incrementTimetableErrors();
                        //timetable = generateErrorBean(1);
                        response.sendError( 500, "Backend didn't answer" );
                } catch (CircuitBreakerException cbe) {
                        logger.warning("Circuitbreaker - failing fast, type=" + type + ", train="+train);
                        Statistics.getInstance().incrementTimetableErrors();                    
                        timetable = generateErrorBean(1);
                }catch (Exception e) {
                        logger.log(Level.WARNING, "failure looking up timetable: type=" + type + ",train=" +train, e);
                        Statistics.getInstance().incrementTimetableErrors();
                        response.sendError(500);
                }
                
                if (timetable != null) {
                        String responseXML = formatTimetable(timetable);
                
                        response.setContentType("text/xml");
                        response.getWriter().print(responseXML);
                }
                
        }
        
        protected TimetableBean generateErrorBean(int code) {
                TimetableBean bean = new TimetableBean();               
                bean.errorCode = code;
                return bean;
        }
        
        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	import java.util.logging.Level;
6	import java.util.logging.Logger;
7
8	import javax.servlet.ServletException;
9	import javax.servlet.annotation.WebServlet;
10	import javax.servlet.http.HttpServlet;
11	import javax.servlet.http.HttpServletRequest;
12	import javax.servlet.http.HttpServletResponse;
13
14	import org.simpleframework.xml.Serializer;
15	import org.simpleframework.xml.core.Persister;
16
17	import dk.thoerup.android.traininfo.common.TimetableBean;
18	import dk.thoerup.circuitbreaker.CircuitBreakerException;
19	import dk.thoerup.traininfoservice.Statistics;
20	import dk.thoerup.traininfoservice.TraininfoSettings;
21
22	/**
23	* Servlet implementation class TimetableServlet
24	*/
25	@WebServlet(urlPatterns={"/TimetableServlet"})
26	public class TimetableServlet extends HttpServlet {
27	private static final long serialVersionUID = 1L;
28
29
30	Logger logger = Logger.getLogger( TimetableServlet.class.getName() );
31
32	TimetableFetcher fetcher;
33
34
35	@Override
36	public void init() throws ServletException {
37	super.init();
38
39
40	TraininfoSettings settings = (TraininfoSettings) getServletContext().getAttribute("settings");
41	fetcher = new TimetableFetcher(settings);
42	}
43
44	@Override
45	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
46	if (request.getParameter("train") == null \|\| request.getParameter("train").equals("") ) {
47	response.sendError(400, "not enough parameters (train)");
48	return;
49	}
50	if (request.getParameter("type") == null \|\| request.getParameter("type").equals("") ) {
51	response.sendError(400, "not enough parameters (type)");
52	return;
53	}
54	Statistics.getInstance().incrementTimetableLookups();
55
56	String train = request.getParameter("train").trim();
57	String type = request.getParameter("type").trim();
58
59
60	TimetableBean timetable = null;
61	try
62	{
63	timetable = fetcher.cachedLookupTimetable(train, type);
64
65	} catch (java.io.IOException ioe) {
66	logger.warning("(timetable) Read failed, type=" + type + ", train="+train + ". " + ioe.getMessage());
67	Statistics.getInstance().incrementTimetableErrors();
68	//timetable = generateErrorBean(1);
69	response.sendError( 500, "Backend didn't answer" );
70	} catch (CircuitBreakerException cbe) {
71	logger.warning("Circuitbreaker - failing fast, type=" + type + ", train="+train);
72	Statistics.getInstance().incrementTimetableErrors();
73	timetable = generateErrorBean(1);
74	}catch (Exception e) {
75	logger.log(Level.WARNING, "failure looking up timetable: type=" + type + ",train=" +train, e);
76	Statistics.getInstance().incrementTimetableErrors();
77	response.sendError(500);
78	}
79
80	if (timetable != null) {
81	String responseXML = formatTimetable(timetable);
82
83	response.setContentType("text/xml");
84	response.getWriter().print(responseXML);
85	}
86
87	}
88
89	protected TimetableBean generateErrorBean(int code) {
90	TimetableBean bean = new TimetableBean();
91	bean.errorCode = code;
92	return bean;
93	}
94
95	String formatTimetable(TimetableBean timetable) throws ServletException {
96	Serializer serializer = new Persister();
97
98	StringWriter out = new StringWriter();
99
100	try {
101	serializer.write(timetable, out);
102	} catch (Exception e) {
103	throw new ServletException(e);
104	}
105
106	return out.toString();
107	}
108
109	}