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;
import dk.thoerup.traininfoservice.banedk.DepartureFetcher.FetchTrainType;

/**
 * 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;
                
                DepartureFetcher.FetchTrainType type = FetchTrainType.BOTH;
                if ( req.getParameter("type") != null) {
                        type = FetchTrainType.valueOf( req.getParameter("type") );
                }

                try {
                        beans = fetcher.cachedLookupDepartures(station, arrival, type);
                        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	package dk.thoerup.traininfoservice.banedk;
2
3	import java.io.File;
4	import java.io.IOException;
5	import java.io.StringReader;
6	import java.io.StringWriter;
7	import java.util.logging.Level;
8	import java.util.logging.Logger;
9
10	import javax.servlet.ServletException;
11	import javax.servlet.annotation.WebServlet;
12	import javax.servlet.http.HttpServlet;
13	import javax.servlet.http.HttpServletRequest;
14	import javax.servlet.http.HttpServletResponse;
15	import javax.xml.transform.Source;
16	import javax.xml.transform.Templates;
17	import javax.xml.transform.Transformer;
18	import javax.xml.transform.TransformerFactory;
19	import javax.xml.transform.stream.StreamResult;
20	import javax.xml.transform.stream.StreamSource;
21
22	import org.simpleframework.xml.Serializer;
23	import org.simpleframework.xml.core.Persister;
24
25	import dk.thoerup.android.traininfo.common.DepartureBean;
26	import dk.thoerup.circuitbreaker.CircuitBreakerException;
27	import dk.thoerup.traininfoservice.StationDAO;
28	import dk.thoerup.traininfoservice.Statistics;
29	import dk.thoerup.traininfoservice.banedk.DepartureFetcher.FetchTrainType;
30
31	/**
32	* Servlet implementation class DepartureServlet
33	*/
34	@WebServlet(urlPatterns={"/DepartureServlet"})
35	public class DepartureServlet extends HttpServlet {
36	private static final long serialVersionUID = 1L;
37
38	Logger logger = Logger.getLogger( DepartureServlet.class.getName() );
39
40	DepartureFetcher fetcher;
41
42
43
44	TransformerFactory xslTransFact;
45	Templates xslTemplate;
46
47
48	@Override
49	public void init() throws ServletException {
50	super.init();
51
52	boolean useAzureSite = Boolean.parseBoolean( getServletContext().getInitParameter("useazuresite") );
53	int cacheTimeout = Integer.parseInt( getServletContext().getInitParameter("cache_timeout") );
54	int replyTimeout = Integer.parseInt( getServletContext().getInitParameter("reply_timeout") );
55	logger.info( "DepartureServlet, use azure site=" + useAzureSite + ", cache=" + cacheTimeout);
56	fetcher = new DepartureFetcher(useAzureSite, cacheTimeout, replyTimeout);
57
58	xslTransFact = TransformerFactory.newInstance();
59
60	String xslPath = getServletContext().getRealPath("/departures.xsl");
61	Source stylesheet = new StreamSource( new File(xslPath) );
62
63	try {
64	xslTemplate = xslTransFact.newTemplates(stylesheet);
65	} catch (Exception e) {
66	throw new ServletException(e);
67	}
68	}
69
70	@Override
71	protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
72	if (req.getParameter("station") == null) {
73	resp.sendError(400, "not enough parameters (station)");
74	return;
75	}
76	if (req.getParameter("format") == null) {
77	resp.sendError(400, "not enough parameters (format)");
78	return;
79	}
80
81	boolean arrival = false;
82	try {
83	arrival = Integer.parseInt( req.getParameter("arrival")) != 0;
84	} catch (Exception e) {}
85
86	Statistics.getInstance().incrementDepartureLookups();
87
88	int station = Integer.parseInt( req.getParameter("station") );
89	String format = req.getParameter("format");
90
91	DepartureBean beans;
92
93	DepartureFetcher.FetchTrainType type = FetchTrainType.BOTH;
94	if ( req.getParameter("type") != null) {
95	type = FetchTrainType.valueOf( req.getParameter("type") );
96	}
97
98	try {
99	beans = fetcher.cachedLookupDepartures(station, arrival, type);
100	beans.arrival = arrival;
101	} catch (java.io.IOException ioe) {
102	logger.warning("Read failed, station="+station + ". " + ioe.getMessage() );
103	Statistics.getInstance().incrementDepartureErrors();
104	resp.sendError(500);
105	return;
106	} catch (CircuitBreakerException cbe) {
107	logger.warning("Circuitbreaker - failing fast, station=" +station);
108	Statistics.getInstance().incrementDepartureErrors();
109	resp.sendError(500);
110	return;
111	} catch (StationDAO.NostationException nse) {
112	logger.log(Level.WARNING, "Station not in Database, station=" +station);
113	Statistics.getInstance().incrementDepartureErrors();
114	resp.sendError(400, "invalid station ID");
115	return;
116	} catch (Exception e) {
117	logger.log(Level.WARNING, "Unknown exception, station=" +station, e);
118	Statistics.getInstance().incrementDepartureErrors();
119	resp.sendError(500);
120	return;
121	}
122
123	resp.setDateHeader("Expires", 0);
124	resp.setHeader("Cache-Control", "no-cache, must-revalidate");
125
126	if (format.equalsIgnoreCase("xml")) {
127	resp.setContentType("text/xml");
128	resp.getWriter().print( formatXml(beans) );
129	} else if (format.equalsIgnoreCase("html")) {
130
131	String advStr = req.getParameter("advanced");
132	boolean advanced = advStr != null ? Boolean.parseBoolean(advStr) : false;
133
134	req.setAttribute("advanced", advanced);
135	req.setAttribute("departurebeans", beans);
136	req.setAttribute("stationID", station );
137	getServletContext().getRequestDispatcher("/ViewDepartures.jsp").forward(req,resp);
138	/*resp.setContentType("text/html");
139	resp.getWriter().print( xmlToHtml(formatXml(beans)) );*/
140	} else {
141	resp.sendError(400, "Unknown format");
142	}
143
144	}
145
146	protected String formatXml(DepartureBean beans) throws ServletException{
147
148	Serializer serializer = new Persister();
149
150	StringWriter out = new StringWriter();
151
152	try {
153	serializer.write(beans, out);
154	} catch (Exception e) {
155	throw new ServletException(e);
156	}
157
158	return out.toString();
159	}
160
161	protected String xmlToHtml(String input) throws ServletException {
162
163	try {
164	Transformer trans = xslTemplate.newTransformer();
165
166
167	Source xml = new StreamSource( new StringReader(input));
168	StringWriter out = new StringWriter();
169	trans.transform(xml, new StreamResult(out));
170
171	return out.toString();
172	} catch (Exception e) {
173	throw new ServletException(e);
174	}
175	}
176
177	}