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;

/**
 * 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;
                }
                
                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);
                } catch (java.io.IOException ioe) {
                        logger.warning("Read failed, station="+station + ". " + ioe.getMessage() );
                        resp.sendError(500);
                        return;
                } catch (CircuitBreakerException cbe) {
                        logger.warning("Circuitbreaker - failing fast");
                        resp.sendError(500);
                        return;
                } catch (Exception e) {                 
                        logger.log(Level.WARNING, "Unknown exception, station=" +station, e);
                        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 {
                        throw new ServletException("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);
                        
                        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", "4");
                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	torben	307	package dk.thoerup.traininfoservice.banedk;
2
3			import java.io.IOException;
4			import java.util.List;
5	torben	348	import java.util.logging.Level;
6			import java.util.logging.Logger;
7	torben	307
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	torben	468	import dk.thoerup.circuitbreaker.CircuitBreakerException;
25	torben	650	import dk.thoerup.traininfoservice.StationDAO;
26	torben	307
27			/**
28			* Servlet implementation class DepartureServlet
29			*/
30			public class DepartureServlet extends HttpServlet {
31			private static final long serialVersionUID = 1L;
32	torben	348
33			Logger logger = Logger.getLogger( DepartureServlet.class.getName() );
34	torben	307
35	torben	580	DepartureFetcher fetcher;
36	torben	307	TransformerFactory transformerFactory = TransformerFactory.newInstance();
37			DocumentBuilderFactory docBuilderFactory = DocumentBuilderFactory.newInstance();
38
39
40	torben	425	@Override
41	torben	580	public void init() throws ServletException {
42			super.init();
43	torben	584
44			boolean useTempSite = Boolean.parseBoolean( getServletContext().getInitParameter("usetempsite") );
45			int cacheTimeout = Integer.parseInt( getServletContext().getInitParameter("cache_timeout") );
46			logger.info( "DepartureServlet, use temp site=" + useTempSite + ", cache=" + cacheTimeout);
47			fetcher = new DepartureFetcher(useTempSite, cacheTimeout);
48	torben	580	}
49
50			@Override
51	torben	307	protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
52	torben	458	if (req.getParameter("station") == null) {
53			resp.sendError(400, "not enough parameters");
54			return;
55			}
56
57	torben	307	int station = Integer.parseInt( req.getParameter("station") );
58			String format = req.getParameter("format");
59
60			List<DepartureBean> beans;
61
62	torben	650	String stationName = StationDAO.getStationName(station);
63	torben	307
64			try {
65	torben	387	beans = fetcher.cachedLookupDepartures(station);
66	torben	462	} catch (java.io.IOException ioe) {
67			logger.warning("Read failed, station="+station + ". " + ioe.getMessage() );
68	torben	348	resp.sendError(500);
69			return;
70	torben	421	} catch (CircuitBreakerException cbe) {
71			logger.warning("Circuitbreaker - failing fast");
72			resp.sendError(500);
73			return;
74	torben	451	} catch (Exception e) {
75	torben	348	logger.log(Level.WARNING, "Unknown exception, station=" +station, e);
76			resp.sendError(500);
77			return;
78	torben	307	}
79
80			resp.setDateHeader("Expires", 0);
81			resp.setHeader("Cache-Control", "no-cache, must-revalidate");
82
83			if (format.equalsIgnoreCase("xml")) {
84			resp.setContentType("text/xml");
85			resp.getWriter().print( formatXml(beans, stationName) );
86			} else if (format.equalsIgnoreCase("html")) {
87	torben	585
88			String advStr = req.getParameter("advanced");
89			boolean advanced = advStr != null ? Boolean.parseBoolean(advStr) : false;
90
91			req.setAttribute("advanced", advanced);
92	torben	307	req.setAttribute("stationname", stationName );
93			req.setAttribute("departurebeans", beans);
94			req.setAttribute("stationID", station );
95			getServletContext().getRequestDispatcher("/ViewDepartures.jsp").forward(req,resp);
96			} else {
97			throw new ServletException("Unknown format");
98			}
99
100			}
101
102			protected String formatXml(List<DepartureBean> beans, String stationName) throws ServletException{
103			String xml = "";
104			try {
105			DocumentBuilder builder = docBuilderFactory.newDocumentBuilder();
106			DOMImplementation impl = builder.getDOMImplementation();
107
108
109			Document doc = impl.createDocument(null,null,null);
110			Element root = doc.createElement("departureinfo");
111			root.setAttribute("station", stationName);
112			for (DepartureBean departure : beans) {
113			Element train = doc.createElement("train");
114
115			Element time = doc.createElement("time");
116			time.setTextContent( departure.getTime() );
117			train.appendChild(time);
118
119			Element updated = doc.createElement("updated");
120			updated.setTextContent( String.valueOf(departure.getUpdated()) );
121			train.appendChild(updated);
122
123			Element trainNumber = doc.createElement("trainnumber");
124			trainNumber.setTextContent( departure.getTrainNumber() );
125			train.appendChild(trainNumber);
126
127			Element destination = doc.createElement("destination");
128			destination.setTextContent( departure.getDestination());
129			train.appendChild(destination);
130
131			Element origin = doc.createElement("origin");
132			origin.setTextContent( departure.getOrigin() );
133			train.appendChild(origin);
134
135			Element location= doc.createElement("location");
136			location.setTextContent( departure.getLocation() );
137			train.appendChild(location);
138
139			Element status = doc.createElement("status");
140			status.setTextContent( departure.getStatus() );
141			train.appendChild(status);
142
143			Element note = doc.createElement("note");
144			note.setTextContent( departure.getNote() );
145			train.appendChild(note);
146
147			root.appendChild(train);
148			}
149
150			doc.appendChild(root);
151
152
153			DOMSource domSource = new DOMSource(doc);
154
155			Transformer transformer = transformerFactory.newTransformer();
156			//transformer.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, "yes");
157			transformer.setOutputProperty(OutputKeys.METHOD, "xml");
158			transformer.setOutputProperty(OutputKeys.ENCODING,"ISO-8859-1");
159			transformer.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "4");
160			transformer.setOutputProperty(OutputKeys.INDENT, "yes");
161			java.io.StringWriter sw = new java.io.StringWriter();
162			StreamResult sr = new StreamResult(sw);
163			transformer.transform(domSource, sr);
164			xml = sw.toString();
165
166
167			} catch (Exception e) {
168			throw new ServletException(e);
169			}
170			return xml;
171			}
172
173			}