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();
        

        @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 = 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")) {
                        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	@Override
44	protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
45	if (req.getParameter("station") == null) {
46	resp.sendError(400, "not enough parameters");
47	return;
48	}
49
50	int station = Integer.parseInt( req.getParameter("station") );
51	String format = req.getParameter("format");
52
53	List<DepartureBean> beans;
54
55	String stationName = getStationName(station);
56
57	try {
58	beans = fetcher.cachedLookupDepartures(station);
59	} catch (java.io.IOException ioe) {
60	logger.warning("Read failed, station="+station + ". " + ioe.getMessage() );
61	resp.sendError(500);
62	return;
63	} catch (CircuitBreakerException cbe) {
64	logger.warning("Circuitbreaker - failing fast");
65	resp.sendError(500);
66	return;
67	} catch (Exception e) {
68	logger.log(Level.WARNING, "Unknown exception, station=" +station, e);
69	resp.sendError(500);
70	return;
71	}
72
73	resp.setDateHeader("Expires", 0);
74	resp.setHeader("Cache-Control", "no-cache, must-revalidate");
75
76	if (format.equalsIgnoreCase("xml")) {
77	resp.setContentType("text/xml");
78	resp.getWriter().print( formatXml(beans, stationName) );
79	} else if (format.equalsIgnoreCase("html")) {
80	req.setAttribute("stationname", stationName );
81	req.setAttribute("departurebeans", beans);
82	req.setAttribute("stationID", station );
83	getServletContext().getRequestDispatcher("/ViewDepartures.jsp").forward(req,resp);
84	} else {
85	throw new ServletException("Unknown format");
86	}
87
88	}
89
90	protected String formatXml(List<DepartureBean> beans, String stationName) throws ServletException{
91	String xml = "";
92	try {
93	DocumentBuilder builder = docBuilderFactory.newDocumentBuilder();
94	DOMImplementation impl = builder.getDOMImplementation();
95
96
97	Document doc = impl.createDocument(null,null,null);
98	Element root = doc.createElement("departureinfo");
99	root.setAttribute("station", stationName);
100	for (DepartureBean departure : beans) {
101	Element train = doc.createElement("train");
102
103	Element time = doc.createElement("time");
104	time.setTextContent( departure.getTime() );
105	train.appendChild(time);
106
107	Element updated = doc.createElement("updated");
108	updated.setTextContent( String.valueOf(departure.getUpdated()) );
109	train.appendChild(updated);
110
111	Element trainNumber = doc.createElement("trainnumber");
112	trainNumber.setTextContent( departure.getTrainNumber() );
113	train.appendChild(trainNumber);
114
115	Element destination = doc.createElement("destination");
116	destination.setTextContent( departure.getDestination());
117	train.appendChild(destination);
118
119	Element origin = doc.createElement("origin");
120	origin.setTextContent( departure.getOrigin() );
121	train.appendChild(origin);
122
123	Element location= doc.createElement("location");
124	location.setTextContent( departure.getLocation() );
125	train.appendChild(location);
126
127	Element status = doc.createElement("status");
128	status.setTextContent( departure.getStatus() );
129	train.appendChild(status);
130
131	Element note = doc.createElement("note");
132	note.setTextContent( departure.getNote() );
133	train.appendChild(note);
134
135	root.appendChild(train);
136	}
137
138	doc.appendChild(root);
139
140
141	DOMSource domSource = new DOMSource(doc);
142
143	Transformer transformer = transformerFactory.newTransformer();
144	//transformer.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, "yes");
145	transformer.setOutputProperty(OutputKeys.METHOD, "xml");
146	transformer.setOutputProperty(OutputKeys.ENCODING,"ISO-8859-1");
147	transformer.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "4");
148	transformer.setOutputProperty(OutputKeys.INDENT, "yes");
149	java.io.StringWriter sw = new java.io.StringWriter();
150	StreamResult sr = new StreamResult(sw);
151	transformer.transform(domSource, sr);
152	xml = sw.toString();
153
154
155	} catch (Exception e) {
156	throw new ServletException(e);
157	}
158	return xml;
159	}
160
161	protected String getStationName(int stationID) {
162	String station = "";
163
164	Connection conn = null;
165	try {
166	conn = DBConnection.getConnection();
167	Statement stmt = conn.createStatement();
168	ResultSet rs = stmt.executeQuery("SELECT name FROM trainstations WHERE id=" + stationID);
169	if (rs.next()) {
170	station = rs.getString(1);
171	}
172
173	} catch (Exception e) {
174	} finally {
175	try {
176	if (conn != null && !conn.isClosed())
177	conn.close();
178	} catch (Exception e) {}
179	}
180
181	return station;
182	}
183
184	}