traininfoservice/banedk/DepartureServlet.java

package dk.thoerup.traininfoservice.banedk;

import java.io.IOException;
import java.util.List;
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.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
 */
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");

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