traininfoservice/banedk/DepartureServlet.java

package dk.thoerup.traininfoservice.banedk;

import java.io.File;
import java.io.IOException;
import java.io.StringReader;
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 javax.xml.transform.Source;
import javax.xml.transform.Templates;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.stream.StreamResult;
import javax.xml.transform.stream.StreamSource;

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

import dk.thoerup.android.traininfo.common.DepartureBean;
import dk.thoerup.circuitbreaker.CircuitBreakerException;
import dk.thoerup.traininfoservice.StationDAO;
import dk.thoerup.traininfoservice.Statistics;

/**
 * Servlet implementation class DepartureServlet
 */
@WebServlet(urlPatterns={"/DepartureServlet"})
public class DepartureServlet extends HttpServlet {
        private static final long serialVersionUID = 1L;
        
        Logger logger = Logger.getLogger( DepartureServlet.class.getName() );

        DepartureFetcher fetcher;


        TransformerFactory xslTransFact;
        Templates xslTemplate;
        

        @Override
        public void init() throws ServletException {
                super.init();

                boolean useAzureSite =  Boolean.parseBoolean( getServletContext().getInitParameter("useazuresite") );
                int cacheTimeout =  Integer.parseInt( getServletContext().getInitParameter("cache_timeout") );
                int replyTimeout =  Integer.parseInt( getServletContext().getInitParameter("reply_timeout") ); 
                logger.info( "DepartureServlet, use azure site=" + useAzureSite + ", cache=" + cacheTimeout);
                fetcher = new DepartureFetcher(useAzureSite, cacheTimeout, replyTimeout);
                
                xslTransFact = TransformerFactory.newInstance();
                
                String xslPath = getServletContext().getRealPath("/departures.xsl");
                Source stylesheet = new StreamSource( new File(xslPath) );
                
                try {
                        xslTemplate = xslTransFact.newTemplates(stylesheet);
                } catch (Exception e) {
                        throw new ServletException(e);
                }
        }

        @Override
        protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {           
                if (req.getParameter("station") == null) {
                        resp.sendError(400, "not enough parameters (station)");
                        return;
                }
                if (req.getParameter("format") == null) {
                        resp.sendError(400, "not enough parameters (format)");
                        return;                 
                }
                
                boolean arrival = false;
                try {
                        arrival = Integer.parseInt( req.getParameter("arrival")) != 0;
                } catch (Exception e) {}
                
                Statistics.getInstance().incrementDepartureLookups();
                
                int station = Integer.parseInt( req.getParameter("station") );
                String format = req.getParameter("format");

                DepartureBean beans;            

                try {
                        beans = fetcher.cachedLookupDepartures(station, arrival);
                        beans.arrival = arrival;
                } catch (java.io.IOException ioe) {
                        logger.warning("Read failed, station="+station + ". " + ioe.getMessage() );
                        Statistics.getInstance().incrementDepartureErrors();
                        resp.sendError(500);
                        return;
                } catch (CircuitBreakerException cbe) {
                        logger.warning("Circuitbreaker - failing fast, station=" +station);
                        Statistics.getInstance().incrementDepartureErrors();
                        resp.sendError(500);
                        return;
                } catch (StationDAO.NostationException nse) {
                        logger.log(Level.WARNING, "Station not in Database, station=" +station);
                        Statistics.getInstance().incrementDepartureErrors();
                        resp.sendError(400, "invalid station ID");
                        return;                 
                } catch (Exception e) {                 
                        logger.log(Level.WARNING, "Unknown exception, station=" +station, e);
                        Statistics.getInstance().incrementDepartureErrors();
                        resp.sendError(500);
                        return;
                }
                
                resp.setDateHeader("Expires", 0);
                resp.setHeader("Cache-Control", "no-cache, must-revalidate");
                
                if (format.equalsIgnoreCase("xml")) {
                        resp.setContentType("text/xml");
                        resp.getWriter().print( formatXml(beans) );
                } else if (format.equalsIgnoreCase("html")) {
                        /*
                        String advStr = req.getParameter("advanced");
                        boolean advanced = advStr != null ? Boolean.parseBoolean(advStr) : false;
                        
                        req.setAttribute("advanced", advanced);
                        req.setAttribute("departurebeans", beans);
                        req.setAttribute("stationID", station );
                        getServletContext().getRequestDispatcher("/ViewDepartures.jsp").forward(req,resp);*/
                        resp.setContentType("text/html");
                        resp.getWriter().print(  xmlToHtml(formatXml(beans))  );
                } else {
                        resp.sendError(400, "Unknown format");                  
                }

        }

        protected String formatXml(DepartureBean beans) throws ServletException{
                
                Serializer serializer = new Persister();

                StringWriter out = new StringWriter();

                try {
                        serializer.write(beans, out);
                } catch (Exception e) {
                        throw new ServletException(e);
                }
                
                return out.toString();
        }
        
        protected String xmlToHtml(String input) throws ServletException {

                try {                                   
                        Transformer trans = xslTemplate.newTransformer();
                        
                
                        Source xml = new StreamSource( new StringReader(input));
                        StringWriter out = new StringWriter();
                        trans.transform(xml, new StreamResult(out));            
                
                        return out.toString();
                } catch (Exception e) {
                        throw new ServletException(e);
                }
        }

}
1	torben	307	package dk.thoerup.traininfoservice.banedk;
2
3	torben	1075	import java.io.File;
4	torben	307	import java.io.IOException;
5	torben	1191	import java.io.StringReader;
6	torben	1190	import java.io.StringWriter;
7	torben	348	import java.util.logging.Level;
8			import java.util.logging.Logger;
9	torben	307
10			import javax.servlet.ServletException;
11	torben	958	import javax.servlet.annotation.WebServlet;
12	torben	307	import javax.servlet.http.HttpServlet;
13			import javax.servlet.http.HttpServletRequest;
14			import javax.servlet.http.HttpServletResponse;
15	torben	1075	import javax.xml.transform.Source;
16	torben	1091	import javax.xml.transform.Templates;
17	torben	1075	import javax.xml.transform.Transformer;
18	torben	307	import javax.xml.transform.TransformerFactory;
19	torben	1075	import javax.xml.transform.stream.StreamResult;
20			import javax.xml.transform.stream.StreamSource;
21	torben	307
22	torben	1060	import org.simpleframework.xml.Serializer;
23			import org.simpleframework.xml.core.Persister;
24	torben	307
25	torben	1061	import dk.thoerup.android.traininfo.common.DepartureBean;
26	torben	468	import dk.thoerup.circuitbreaker.CircuitBreakerException;
27	torben	1145	import dk.thoerup.traininfoservice.StationDAO;
28	torben	711	import dk.thoerup.traininfoservice.Statistics;
29	torben	307
30			/**
31			* Servlet implementation class DepartureServlet
32			*/
33	torben	958	@WebServlet(urlPatterns={"/DepartureServlet"})
34	torben	307	public class DepartureServlet extends HttpServlet {
35			private static final long serialVersionUID = 1L;
36	torben	348
37			Logger logger = Logger.getLogger( DepartureServlet.class.getName() );
38	torben	307
39	torben	580	DepartureFetcher fetcher;
40	torben	1075
41
42	torben	307
43	torben	1091	TransformerFactory xslTransFact;
44			Templates xslTemplate;
45	torben	1075
46	torben	307
47	torben	425	@Override
48	torben	580	public void init() throws ServletException {
49			super.init();
50	torben	584
51	torben	1034	boolean useAzureSite = Boolean.parseBoolean( getServletContext().getInitParameter("useazuresite") );
52	torben	584	int cacheTimeout = Integer.parseInt( getServletContext().getInitParameter("cache_timeout") );
53	torben	1026	int replyTimeout = Integer.parseInt( getServletContext().getInitParameter("reply_timeout") );
54	torben	1036	logger.info( "DepartureServlet, use azure site=" + useAzureSite + ", cache=" + cacheTimeout);
55	torben	1034	fetcher = new DepartureFetcher(useAzureSite, cacheTimeout, replyTimeout);
56	torben	1075
57	torben	1091	xslTransFact = TransformerFactory.newInstance();
58
59			String xslPath = getServletContext().getRealPath("/departures.xsl");
60			Source stylesheet = new StreamSource( new File(xslPath) );
61
62			try {
63			xslTemplate = xslTransFact.newTemplates(stylesheet);
64			} catch (Exception e) {
65			throw new ServletException(e);
66			}
67	torben	580	}
68
69			@Override
70	torben	711	protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
71	torben	458	if (req.getParameter("station") == null) {
72	torben	1168	resp.sendError(400, "not enough parameters (station)");
73	torben	458	return;
74			}
75	torben	1168	if (req.getParameter("format") == null) {
76			resp.sendError(400, "not enough parameters (format)");
77			return;
78			}
79	torben	829
80			boolean arrival = false;
81			try {
82			arrival = Integer.parseInt( req.getParameter("arrival")) != 0;
83			} catch (Exception e) {}
84
85	torben	711	Statistics.getInstance().incrementDepartureLookups();
86	torben	458
87	torben	307	int station = Integer.parseInt( req.getParameter("station") );
88			String format = req.getParameter("format");
89
90	torben	1021	DepartureBean beans;
91	torben	307
92			try {
93	torben	829	beans = fetcher.cachedLookupDepartures(station, arrival);
94	torben	1074	beans.arrival = arrival;
95	torben	462	} catch (java.io.IOException ioe) {
96			logger.warning("Read failed, station="+station + ". " + ioe.getMessage() );
97	torben	716	Statistics.getInstance().incrementDepartureErrors();
98	torben	348	resp.sendError(500);
99			return;
100	torben	421	} catch (CircuitBreakerException cbe) {
101	torben	1158	logger.warning("Circuitbreaker - failing fast, station=" +station);
102	torben	716	Statistics.getInstance().incrementDepartureErrors();
103	torben	421	resp.sendError(500);
104			return;
105	torben	1145	} catch (StationDAO.NostationException nse) {
106			logger.log(Level.WARNING, "Station not in Database, station=" +station);
107			Statistics.getInstance().incrementDepartureErrors();
108			resp.sendError(400, "invalid station ID");
109			return;
110	torben	451	} catch (Exception e) {
111	torben	348	logger.log(Level.WARNING, "Unknown exception, station=" +station, e);
112	torben	716	Statistics.getInstance().incrementDepartureErrors();
113	torben	348	resp.sendError(500);
114			return;
115	torben	307	}
116
117			resp.setDateHeader("Expires", 0);
118			resp.setHeader("Cache-Control", "no-cache, must-revalidate");
119
120			if (format.equalsIgnoreCase("xml")) {
121			resp.setContentType("text/xml");
122	torben	1074	resp.getWriter().print( formatXml(beans) );
123	torben	307	} else if (format.equalsIgnoreCase("html")) {
124	torben	1075	/*
125	torben	585	String advStr = req.getParameter("advanced");
126			boolean advanced = advStr != null ? Boolean.parseBoolean(advStr) : false;
127
128			req.setAttribute("advanced", advanced);
129	torben	307	req.setAttribute("departurebeans", beans);
130			req.setAttribute("stationID", station );
131	torben	1075	getServletContext().getRequestDispatcher("/ViewDepartures.jsp").forward(req,resp);*/
132			resp.setContentType("text/html");
133			resp.getWriter().print( xmlToHtml(formatXml(beans)) );
134	torben	307	} else {
135	torben	862	resp.sendError(400, "Unknown format");
136	torben	307	}
137
138			}
139
140	torben	1074	protected String formatXml(DepartureBean beans) throws ServletException{
141	torben	1060
142			Serializer serializer = new Persister();
143	torben	307
144	torben	1190	StringWriter out = new StringWriter();
145	torben	307
146	torben	1060	try {
147			serializer.write(beans, out);
148	torben	307	} catch (Exception e) {
149			throw new ServletException(e);
150			}
151	torben	1060
152			return out.toString();
153	torben	307	}
154	torben	1075
155	torben	1091	protected String xmlToHtml(String input) throws ServletException {
156	torben	307
157	torben	1091	try {
158	torben	1191	Transformer trans = xslTemplate.newTransformer();
159
160	torben	1075
161	torben	1191	Source xml = new StreamSource( new StringReader(input));
162	torben	1190	StringWriter out = new StringWriter();
163	torben	1075	trans.transform(xml, new StreamResult(out));
164
165			return out.toString();
166			} catch (Exception e) {
167	torben	1091	throw new ServletException(e);
168	torben	1075	}
169			}
170
171	torben	307	}