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.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.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");
                        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");
                        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();

                ByteArrayOutputStream out = new ByteArrayOutputStream();

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