traininfoservice/banedk/DepartureServlet.java

package dk.thoerup.traininfoservice.banedk;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.File;
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.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.core.Persister;

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

/**
 * Servlet implementation class 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");
                        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");
                        Statistics.getInstance().incrementDepartureErrors();
                        resp.sendError(500);
                        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; charset=utf-8");
                        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{
                
                Persister 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 ByteArrayInputStream(input.getBytes() ));
                        ByteArrayOutputStream out = new ByteArrayOutputStream();
                        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.ByteArrayInputStream;
4	torben	1060	import java.io.ByteArrayOutputStream;
5	torben	1075	import java.io.File;
6	torben	307	import java.io.IOException;
7	torben	1092	import java.io.StringWriter;
8	torben	348	import java.util.logging.Level;
9			import java.util.logging.Logger;
10	torben	307
11			import javax.servlet.ServletException;
12			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	1092	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.core.Persister;
23	torben	307
24	torben	1061	import dk.thoerup.android.traininfo.common.DepartureBean;
25	torben	468	import dk.thoerup.circuitbreaker.CircuitBreakerException;
26	torben	711	import dk.thoerup.traininfoservice.Statistics;
27	torben	307
28			/**
29			* Servlet implementation class DepartureServlet
30			*/
31	torben	1080
32	torben	307	public class DepartureServlet extends HttpServlet {
33			private static final long serialVersionUID = 1L;
34	torben	348
35			Logger logger = Logger.getLogger( DepartureServlet.class.getName() );
36	torben	307
37	torben	580	DepartureFetcher fetcher;
38	torben	1075
39
40	torben	307
41	torben	1075
42	torben	1092
43			TransformerFactory xslTransFact;
44			Templates xslTemplate;
45	torben	307
46	torben	425	@Override
47	torben	580	public void init() throws ServletException {
48			super.init();
49	torben	584
50	torben	1034	boolean useAzureSite = Boolean.parseBoolean( getServletContext().getInitParameter("useazuresite") );
51	torben	584	int cacheTimeout = Integer.parseInt( getServletContext().getInitParameter("cache_timeout") );
52	torben	1026	int replyTimeout = Integer.parseInt( getServletContext().getInitParameter("reply_timeout") );
53	torben	1036	logger.info( "DepartureServlet, use azure site=" + useAzureSite + ", cache=" + cacheTimeout);
54	torben	1034	fetcher = new DepartureFetcher(useAzureSite, cacheTimeout, replyTimeout);
55	torben	1075
56	torben	1092
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	torben	580	}
69
70			@Override
71	torben	711	protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
72	torben	458	if (req.getParameter("station") == null) {
73			resp.sendError(400, "not enough parameters");
74			return;
75			}
76	torben	829
77			boolean arrival = false;
78			try {
79			arrival = Integer.parseInt( req.getParameter("arrival")) != 0;
80			} catch (Exception e) {}
81
82	torben	711	Statistics.getInstance().incrementDepartureLookups();
83	torben	458
84	torben	307	int station = Integer.parseInt( req.getParameter("station") );
85			String format = req.getParameter("format");
86
87	torben	1021	DepartureBean beans;
88	torben	307
89			try {
90	torben	829	beans = fetcher.cachedLookupDepartures(station, arrival);
91	torben	1074	beans.arrival = arrival;
92	torben	462	} catch (java.io.IOException ioe) {
93			logger.warning("Read failed, station="+station + ". " + ioe.getMessage() );
94	torben	716	Statistics.getInstance().incrementDepartureErrors();
95	torben	348	resp.sendError(500);
96			return;
97	torben	421	} catch (CircuitBreakerException cbe) {
98			logger.warning("Circuitbreaker - failing fast");
99	torben	716	Statistics.getInstance().incrementDepartureErrors();
100	torben	421	resp.sendError(500);
101			return;
102	torben	451	} catch (Exception e) {
103	torben	348	logger.log(Level.WARNING, "Unknown exception, station=" +station, e);
104	torben	716	Statistics.getInstance().incrementDepartureErrors();
105	torben	348	resp.sendError(500);
106			return;
107	torben	307	}
108
109			resp.setDateHeader("Expires", 0);
110			resp.setHeader("Cache-Control", "no-cache, must-revalidate");
111
112			if (format.equalsIgnoreCase("xml")) {
113	torben	1092	resp.setContentType("text/xml; charset=utf-8");
114	torben	1074	resp.getWriter().print( formatXml(beans) );
115	torben	1092
116
117	torben	307	} else if (format.equalsIgnoreCase("html")) {
118	torben	1075	/*
119	torben	585	String advStr = req.getParameter("advanced");
120			boolean advanced = advStr != null ? Boolean.parseBoolean(advStr) : false;
121
122			req.setAttribute("advanced", advanced);
123	torben	307	req.setAttribute("departurebeans", beans);
124			req.setAttribute("stationID", station );
125	torben	1075	getServletContext().getRequestDispatcher("/ViewDepartures.jsp").forward(req,resp);*/
126			resp.setContentType("text/html");
127			resp.getWriter().print( xmlToHtml(formatXml(beans)) );
128	torben	307	} else {
129	torben	862	resp.sendError(400, "Unknown format");
130	torben	307	}
131
132			}
133
134	torben	1074	protected String formatXml(DepartureBean beans) throws ServletException{
135	torben	1060
136	torben	1092	Persister serializer = new Persister();
137	torben	307
138	torben	1092
139			StringWriter out = new StringWriter();
140
141			try {
142	torben	1060	serializer.write(beans, out);
143	torben	307	} catch (Exception e) {
144			throw new ServletException(e);
145			}
146	torben	1060
147			return out.toString();
148	torben	307	}
149	torben	1075
150	torben	1092	protected String xmlToHtml(String input) throws ServletException {
151	torben	307
152	torben	1092	try {
153			Transformer trans = xslTemplate.newTransformer();
154	torben	1075
155			Source xml = new StreamSource( new ByteArrayInputStream(input.getBytes() ));
156			ByteArrayOutputStream out = new ByteArrayOutputStream();
157			trans.transform(xml, new StreamResult(out));
158
159			return out.toString();
160			} catch (Exception e) {
161	torben	1092	throw new ServletException(e);
162	torben	1075	}
163			}
164
165	torben	307	}