traininfoservice/banedk/DepartureServlet.java

package dk.thoerup.traininfoservice.banedk;

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.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.transform.OutputKeys;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;

import org.w3c.dom.DOMImplementation;
import org.w3c.dom.Document;
import org.w3c.dom.Element;

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 transformerFactory = TransformerFactory.newInstance();
        DocumentBuilderFactory docBuilderFactory = DocumentBuilderFactory.newInstance();
        

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

                boolean useTempSite =  Boolean.parseBoolean( getServletContext().getInitParameter("usetempsite") );
                int cacheTimeout =  Integer.parseInt( getServletContext().getInitParameter("cache_timeout") );
                logger.info( "DepartureServlet, use temp site=" + useTempSite + ", cache=" + cacheTimeout);
                fetcher = new DepartureFetcher(useTempSite, cacheTimeout);
        }

        @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;

                String stationName = StationDAO.getStationName(station);

                try {
                        beans = fetcher.cachedLookupDepartures(station, 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, stationName, arrival) );
                } else if (format.equalsIgnoreCase("html")) {
                        
                        String advStr = req.getParameter("advanced");
                        boolean advanced = advStr != null ? Boolean.parseBoolean(advStr) : false;
                        
                        req.setAttribute("advanced", advanced);
                        req.setAttribute("stationname", stationName );
                        req.setAttribute("departurebeans", beans);
                        req.setAttribute("stationID", station );
                        getServletContext().getRequestDispatcher("/ViewDepartures.jsp").forward(req,resp);
                } else {
                        resp.sendError(400, "Unknown format");                  
                }

        }

        protected String formatXml(DepartureBean beans, String stationName, boolean arrival) throws ServletException{
                String xml = "";
                try {
                        DocumentBuilder builder = docBuilderFactory.newDocumentBuilder();
                        DOMImplementation impl = builder.getDOMImplementation();

                        
                        Document doc = impl.createDocument(null,null,null);
                Element root = doc.createElement("departureinfo");
                root.setAttribute("station", stationName);
                root.setAttribute("arrival", Boolean.toString(arrival) );
                
                for (String notif : beans.notifications) {
                        Element notElem = doc.createElement("notification");
                        notElem.setTextContent(notif);
                        root.appendChild(notElem); 
                }
                
                for (DepartureEntry departure : beans.departureEntries) {
                        Element train = doc.createElement("train");
                        
                        Element time = doc.createElement("time");
                        time.setTextContent( departure.getTime() );
                        train.appendChild(time);
                        
                        Element updated = doc.createElement("updated");
                        updated.setTextContent( String.valueOf(departure.getUpdated()) );
                        train.appendChild(updated);
                        
                        Element trainNumber = doc.createElement("trainnumber");
                        trainNumber.setTextContent( departure.getTrainNumber() );
                        train.appendChild(trainNumber);
                        
                        Element destination = doc.createElement("destination");
                        destination.setTextContent( departure.getDestination());
                        train.appendChild(destination);
                        
                        Element origin = doc.createElement("origin");
                        origin.setTextContent( departure.getOrigin() );
                        train.appendChild(origin);
                        
                        Element location= doc.createElement("location");
                        location.setTextContent( departure.getLocation() );
                        train.appendChild(location);
                        
                        Element status = doc.createElement("status");
                        status.setTextContent( departure.getStatus() );
                        train.appendChild(status);
                        
                        Element note = doc.createElement("note");
                        note.setTextContent( departure.getNote() );
                        train.appendChild(note);
                        
                        Element type = doc.createElement("type");
                        type.setTextContent( departure.getType() );
                        train.appendChild(type);
                        
                        root.appendChild(train);
                }
                
                doc.appendChild(root);
                
                
                DOMSource domSource = new DOMSource(doc);

                Transformer transformer = transformerFactory.newTransformer();
                //transformer.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, "yes");
                transformer.setOutputProperty(OutputKeys.METHOD, "xml");
                transformer.setOutputProperty(OutputKeys.ENCODING,"ISO-8859-1");
                transformer.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "1");
                transformer.setOutputProperty(OutputKeys.INDENT, "yes");
                java.io.StringWriter sw = new java.io.StringWriter();
                StreamResult sr = new StreamResult(sw);
                transformer.transform(domSource, sr);
                xml = sw.toString();


                } catch (Exception e) {
                        throw new ServletException(e);
                }
                return xml;
        }

}
1	package dk.thoerup.traininfoservice.banedk;
2
3	import java.io.IOException;
4	import java.util.logging.Level;
5	import java.util.logging.Logger;
6
7	import javax.servlet.ServletException;
8	import javax.servlet.annotation.WebServlet;
9	import javax.servlet.http.HttpServlet;
10	import javax.servlet.http.HttpServletRequest;
11	import javax.servlet.http.HttpServletResponse;
12	import javax.xml.parsers.DocumentBuilder;
13	import javax.xml.parsers.DocumentBuilderFactory;
14	import javax.xml.transform.OutputKeys;
15	import javax.xml.transform.Transformer;
16	import javax.xml.transform.TransformerFactory;
17	import javax.xml.transform.dom.DOMSource;
18	import javax.xml.transform.stream.StreamResult;
19
20	import org.w3c.dom.DOMImplementation;
21	import org.w3c.dom.Document;
22	import org.w3c.dom.Element;
23
24	import dk.thoerup.circuitbreaker.CircuitBreakerException;
25	import dk.thoerup.traininfoservice.StationDAO;
26	import dk.thoerup.traininfoservice.Statistics;
27
28	/**
29	* Servlet implementation class DepartureServlet
30	*/
31	@WebServlet(urlPatterns={"/DepartureServlet"})
32	public class DepartureServlet extends HttpServlet {
33	private static final long serialVersionUID = 1L;
34
35	Logger logger = Logger.getLogger( DepartureServlet.class.getName() );
36
37	DepartureFetcher fetcher;
38	TransformerFactory transformerFactory = TransformerFactory.newInstance();
39	DocumentBuilderFactory docBuilderFactory = DocumentBuilderFactory.newInstance();
40
41
42	@Override
43	public void init() throws ServletException {
44	super.init();
45
46	boolean useTempSite = Boolean.parseBoolean( getServletContext().getInitParameter("usetempsite") );
47	int cacheTimeout = Integer.parseInt( getServletContext().getInitParameter("cache_timeout") );
48	logger.info( "DepartureServlet, use temp site=" + useTempSite + ", cache=" + cacheTimeout);
49	fetcher = new DepartureFetcher(useTempSite, cacheTimeout);
50	}
51
52	@Override
53	protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
54	if (req.getParameter("station") == null) {
55	resp.sendError(400, "not enough parameters");
56	return;
57	}
58
59	boolean arrival = false;
60	try {
61	arrival = Integer.parseInt( req.getParameter("arrival")) != 0;
62	} catch (Exception e) {}
63
64	Statistics.getInstance().incrementDepartureLookups();
65
66	int station = Integer.parseInt( req.getParameter("station") );
67	String format = req.getParameter("format");
68
69	DepartureBean beans;
70
71	String stationName = StationDAO.getStationName(station);
72
73	try {
74	beans = fetcher.cachedLookupDepartures(station, arrival);
75	} catch (java.io.IOException ioe) {
76	logger.warning("Read failed, station="+station + ". " + ioe.getMessage() );
77	Statistics.getInstance().incrementDepartureErrors();
78	resp.sendError(500);
79	return;
80	} catch (CircuitBreakerException cbe) {
81	logger.warning("Circuitbreaker - failing fast");
82	Statistics.getInstance().incrementDepartureErrors();
83	resp.sendError(500);
84	return;
85	} catch (Exception e) {
86	logger.log(Level.WARNING, "Unknown exception, station=" +station, e);
87	Statistics.getInstance().incrementDepartureErrors();
88	resp.sendError(500);
89	return;
90	}
91
92	resp.setDateHeader("Expires", 0);
93	resp.setHeader("Cache-Control", "no-cache, must-revalidate");
94
95	if (format.equalsIgnoreCase("xml")) {
96	resp.setContentType("text/xml");
97	resp.getWriter().print( formatXml(beans, stationName, arrival) );
98	} else if (format.equalsIgnoreCase("html")) {
99
100	String advStr = req.getParameter("advanced");
101	boolean advanced = advStr != null ? Boolean.parseBoolean(advStr) : false;
102
103	req.setAttribute("advanced", advanced);
104	req.setAttribute("stationname", stationName );
105	req.setAttribute("departurebeans", beans);
106	req.setAttribute("stationID", station );
107	getServletContext().getRequestDispatcher("/ViewDepartures.jsp").forward(req,resp);
108	} else {
109	resp.sendError(400, "Unknown format");
110	}
111
112	}
113
114	protected String formatXml(DepartureBean beans, String stationName, boolean arrival) throws ServletException{
115	String xml = "";
116	try {
117	DocumentBuilder builder = docBuilderFactory.newDocumentBuilder();
118	DOMImplementation impl = builder.getDOMImplementation();
119
120
121	Document doc = impl.createDocument(null,null,null);
122	Element root = doc.createElement("departureinfo");
123	root.setAttribute("station", stationName);
124	root.setAttribute("arrival", Boolean.toString(arrival) );
125
126	for (String notif : beans.notifications) {
127	Element notElem = doc.createElement("notification");
128	notElem.setTextContent(notif);
129	root.appendChild(notElem);
130	}
131
132	for (DepartureEntry departure : beans.departureEntries) {
133	Element train = doc.createElement("train");
134
135	Element time = doc.createElement("time");
136	time.setTextContent( departure.getTime() );
137	train.appendChild(time);
138
139	Element updated = doc.createElement("updated");
140	updated.setTextContent( String.valueOf(departure.getUpdated()) );
141	train.appendChild(updated);
142
143	Element trainNumber = doc.createElement("trainnumber");
144	trainNumber.setTextContent( departure.getTrainNumber() );
145	train.appendChild(trainNumber);
146
147	Element destination = doc.createElement("destination");
148	destination.setTextContent( departure.getDestination());
149	train.appendChild(destination);
150
151	Element origin = doc.createElement("origin");
152	origin.setTextContent( departure.getOrigin() );
153	train.appendChild(origin);
154
155	Element location= doc.createElement("location");
156	location.setTextContent( departure.getLocation() );
157	train.appendChild(location);
158
159	Element status = doc.createElement("status");
160	status.setTextContent( departure.getStatus() );
161	train.appendChild(status);
162
163	Element note = doc.createElement("note");
164	note.setTextContent( departure.getNote() );
165	train.appendChild(note);
166
167	Element type = doc.createElement("type");
168	type.setTextContent( departure.getType() );
169	train.appendChild(type);
170
171	root.appendChild(train);
172	}
173
174	doc.appendChild(root);
175
176
177	DOMSource domSource = new DOMSource(doc);
178
179	Transformer transformer = transformerFactory.newTransformer();
180	//transformer.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, "yes");
181	transformer.setOutputProperty(OutputKeys.METHOD, "xml");
182	transformer.setOutputProperty(OutputKeys.ENCODING,"ISO-8859-1");
183	transformer.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "1");
184	transformer.setOutputProperty(OutputKeys.INDENT, "yes");
185	java.io.StringWriter sw = new java.io.StringWriter();
186	StreamResult sr = new StreamResult(sw);
187	transformer.transform(domSource, sr);
188	xml = sw.toString();
189
190
191	} catch (Exception e) {
192	throw new ServletException(e);
193	}
194	return xml;
195	}
196
197	}