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);
                        
                        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", "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	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
27	/**
28	* Servlet implementation class DepartureServlet
29	*/
30	public class DepartureServlet extends HttpServlet {
31	private static final long serialVersionUID = 1L;
32
33	Logger logger = Logger.getLogger( DepartureServlet.class.getName() );
34
35	DepartureFetcher fetcher;
36	TransformerFactory transformerFactory = TransformerFactory.newInstance();
37	DocumentBuilderFactory docBuilderFactory = DocumentBuilderFactory.newInstance();
38
39
40	@Override
41	public void init() throws ServletException {
42	super.init();
43
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	}
49
50	@Override
51	protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
52	if (req.getParameter("station") == null) {
53	resp.sendError(400, "not enough parameters");
54	return;
55	}
56
57	int station = Integer.parseInt( req.getParameter("station") );
58	String format = req.getParameter("format");
59
60	List<DepartureBean> beans;
61
62	String stationName = StationDAO.getStationName(station);
63
64	try {
65	beans = fetcher.cachedLookupDepartures(station);
66	} catch (java.io.IOException ioe) {
67	logger.warning("Read failed, station="+station + ". " + ioe.getMessage() );
68	resp.sendError(500);
69	return;
70	} catch (CircuitBreakerException cbe) {
71	logger.warning("Circuitbreaker - failing fast");
72	resp.sendError(500);
73	return;
74	} catch (Exception e) {
75	logger.log(Level.WARNING, "Unknown exception, station=" +station, e);
76	resp.sendError(500);
77	return;
78	}
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
88	String advStr = req.getParameter("advanced");
89	boolean advanced = advStr != null ? Boolean.parseBoolean(advStr) : false;
90
91	req.setAttribute("advanced", advanced);
92	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	Element type = doc.createElement("type");
148	type.setTextContent( departure.getType() );
149	train.appendChild(type);
150
151	root.appendChild(train);
152	}
153
154	doc.appendChild(root);
155
156
157	DOMSource domSource = new DOMSource(doc);
158
159	Transformer transformer = transformerFactory.newTransformer();
160	//transformer.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, "yes");
161	transformer.setOutputProperty(OutputKeys.METHOD, "xml");
162	transformer.setOutputProperty(OutputKeys.ENCODING,"ISO-8859-1");
163	transformer.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "4");
164	transformer.setOutputProperty(OutputKeys.INDENT, "yes");
165	java.io.StringWriter sw = new java.io.StringWriter();
166	StreamResult sr = new StreamResult(sw);
167	transformer.transform(domSource, sr);
168	xml = sw.toString();
169
170
171	} catch (Exception e) {
172	throw new ServletException(e);
173	}
174	return xml;
175	}
176
177	}