traininfoservice/banedk/DepartureServlet.java

package dk.thoerup.traininfoservice.banedk;

import java.io.IOException;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.Statement;
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.curcuitbreaker.CircuitBreakerException;
import dk.thoerup.traininfoservice.DBConnection;

/**
 * Servlet implementation class DepartureServlet
 */
public class DepartureServlet extends HttpServlet {
        private static final long serialVersionUID = 1L;
        
        Logger logger = Logger.getLogger( DepartureServlet.class.getName() );

        DepartureFetcher fetcher = new DepartureFetcher();
    TransformerFactory transformerFactory = TransformerFactory.newInstance();
        DocumentBuilderFactory docBuilderFactory = DocumentBuilderFactory.newInstance();
        

        protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
                int station = Integer.parseInt( req.getParameter("station") );
                String format = req.getParameter("format");

                List<DepartureBean> beans;

                String stationName = getStationName(station);

                try {
                        beans = fetcher.cachedLookupDepartures(station);
                } catch (java.net.SocketTimeoutException ste) {
                        logger.warning("Read timed out, station="+station);
                        resp.sendError(500);
                        return;
                } catch (CircuitBreakerException cbe) {
                        logger.warning("Circuitbreaker - failing fast");
                        resp.sendError(500);
                        return;
                } catch (Throwable 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")) {
                        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;
        }

        protected String getStationName(int stationID) {
                String station = "";

                Connection conn = null;
                try {
                        conn = DBConnection.getConnection();
                        Statement stmt = conn.createStatement();
                        ResultSet rs = stmt.executeQuery("SELECT name FROM trainstations WHERE id=" + stationID);
                        if (rs.next()) {
                                station = rs.getString(1);
                        }

                } catch (Exception e) { 
                } finally {
                        try {
                                if (conn != null && !conn.isClosed())
                                        conn.close();
                        } catch (Exception e) {}
                }

                return station;
        }

}
1	package dk.thoerup.traininfoservice.banedk;
2
3	import java.io.IOException;
4	import java.sql.Connection;
5	import java.sql.ResultSet;
6	import java.sql.Statement;
7	import java.util.List;
8	import java.util.logging.Level;
9	import java.util.logging.Logger;
10
11	import javax.servlet.ServletException;
12	import javax.servlet.http.HttpServlet;
13	import javax.servlet.http.HttpServletRequest;
14	import javax.servlet.http.HttpServletResponse;
15	import javax.xml.parsers.DocumentBuilder;
16	import javax.xml.parsers.DocumentBuilderFactory;
17	import javax.xml.transform.OutputKeys;
18	import javax.xml.transform.Transformer;
19	import javax.xml.transform.TransformerFactory;
20	import javax.xml.transform.dom.DOMSource;
21	import javax.xml.transform.stream.StreamResult;
22
23	import org.w3c.dom.DOMImplementation;
24	import org.w3c.dom.Document;
25	import org.w3c.dom.Element;
26
27	import dk.thoerup.curcuitbreaker.CircuitBreakerException;
28	import dk.thoerup.traininfoservice.DBConnection;
29
30	/**
31	* Servlet implementation class DepartureServlet
32	*/
33	public class DepartureServlet extends HttpServlet {
34	private static final long serialVersionUID = 1L;
35
36	Logger logger = Logger.getLogger( DepartureServlet.class.getName() );
37
38	DepartureFetcher fetcher = new DepartureFetcher();
39	TransformerFactory transformerFactory = TransformerFactory.newInstance();
40	DocumentBuilderFactory docBuilderFactory = DocumentBuilderFactory.newInstance();
41
42
43	protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
44	int station = Integer.parseInt( req.getParameter("station") );
45	String format = req.getParameter("format");
46
47	List<DepartureBean> beans;
48
49	String stationName = getStationName(station);
50
51	try {
52	beans = fetcher.cachedLookupDepartures(station);
53	} catch (java.net.SocketTimeoutException ste) {
54	logger.warning("Read timed out, station="+station);
55	resp.sendError(500);
56	return;
57	} catch (CircuitBreakerException cbe) {
58	logger.warning("Circuitbreaker - failing fast");
59	resp.sendError(500);
60	return;
61	} catch (Throwable e) {
62	logger.log(Level.WARNING, "Unknown exception, station=" +station, e);
63	resp.sendError(500);
64	return;
65	}
66
67	resp.setDateHeader("Expires", 0);
68	resp.setHeader("Cache-Control", "no-cache, must-revalidate");
69
70	if (format.equalsIgnoreCase("xml")) {
71	resp.setContentType("text/xml");
72	resp.getWriter().print( formatXml(beans, stationName) );
73	} else if (format.equalsIgnoreCase("html")) {
74	req.setAttribute("stationname", stationName );
75	req.setAttribute("departurebeans", beans);
76	req.setAttribute("stationID", station );
77	getServletContext().getRequestDispatcher("/ViewDepartures.jsp").forward(req,resp);
78	} else {
79	throw new ServletException("Unknown format");
80	}
81
82	}
83
84	protected String formatXml(List<DepartureBean> beans, String stationName) throws ServletException{
85	String xml = "";
86	try {
87	DocumentBuilder builder = docBuilderFactory.newDocumentBuilder();
88	DOMImplementation impl = builder.getDOMImplementation();
89
90
91	Document doc = impl.createDocument(null,null,null);
92	Element root = doc.createElement("departureinfo");
93	root.setAttribute("station", stationName);
94	for (DepartureBean departure : beans) {
95	Element train = doc.createElement("train");
96
97	Element time = doc.createElement("time");
98	time.setTextContent( departure.getTime() );
99	train.appendChild(time);
100
101	Element updated = doc.createElement("updated");
102	updated.setTextContent( String.valueOf(departure.getUpdated()) );
103	train.appendChild(updated);
104
105	Element trainNumber = doc.createElement("trainnumber");
106	trainNumber.setTextContent( departure.getTrainNumber() );
107	train.appendChild(trainNumber);
108
109	Element destination = doc.createElement("destination");
110	destination.setTextContent( departure.getDestination());
111	train.appendChild(destination);
112
113	Element origin = doc.createElement("origin");
114	origin.setTextContent( departure.getOrigin() );
115	train.appendChild(origin);
116
117	Element location= doc.createElement("location");
118	location.setTextContent( departure.getLocation() );
119	train.appendChild(location);
120
121	Element status = doc.createElement("status");
122	status.setTextContent( departure.getStatus() );
123	train.appendChild(status);
124
125	Element note = doc.createElement("note");
126	note.setTextContent( departure.getNote() );
127	train.appendChild(note);
128
129	root.appendChild(train);
130	}
131
132	doc.appendChild(root);
133
134
135	DOMSource domSource = new DOMSource(doc);
136
137	Transformer transformer = transformerFactory.newTransformer();
138	//transformer.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, "yes");
139	transformer.setOutputProperty(OutputKeys.METHOD, "xml");
140	transformer.setOutputProperty(OutputKeys.ENCODING,"ISO-8859-1");
141	transformer.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "4");
142	transformer.setOutputProperty(OutputKeys.INDENT, "yes");
143	java.io.StringWriter sw = new java.io.StringWriter();
144	StreamResult sr = new StreamResult(sw);
145	transformer.transform(domSource, sr);
146	xml = sw.toString();
147
148
149	} catch (Exception e) {
150	throw new ServletException(e);
151	}
152	return xml;
153	}
154
155	protected String getStationName(int stationID) {
156	String station = "";
157
158	Connection conn = null;
159	try {
160	conn = DBConnection.getConnection();
161	Statement stmt = conn.createStatement();
162	ResultSet rs = stmt.executeQuery("SELECT name FROM trainstations WHERE id=" + stationID);
163	if (rs.next()) {
164	station = rs.getString(1);
165	}
166
167	} catch (Exception e) {
168	} finally {
169	try {
170	if (conn != null && !conn.isClosed())
171	conn.close();
172	} catch (Exception e) {}
173	}
174
175	return station;
176	}
177
178	}