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.circuitbreaker.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;
    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 = 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;
        }

        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	torben	307	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	torben	348	import java.util.logging.Level;
9			import java.util.logging.Logger;
10	torben	307
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	torben	468	import dk.thoerup.circuitbreaker.CircuitBreakerException;
28	torben	307	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	torben	348
36			Logger logger = Logger.getLogger( DepartureServlet.class.getName() );
37	torben	307
38	torben	580	DepartureFetcher fetcher;
39	torben	307	TransformerFactory transformerFactory = TransformerFactory.newInstance();
40			DocumentBuilderFactory docBuilderFactory = DocumentBuilderFactory.newInstance();
41
42
43	torben	425	@Override
44	torben	580	public void init() throws ServletException {
45			super.init();
46	torben	584
47			boolean useTempSite = Boolean.parseBoolean( getServletContext().getInitParameter("usetempsite") );
48			int cacheTimeout = Integer.parseInt( getServletContext().getInitParameter("cache_timeout") );
49			logger.info( "DepartureServlet, use temp site=" + useTempSite + ", cache=" + cacheTimeout);
50			fetcher = new DepartureFetcher(useTempSite, cacheTimeout);
51	torben	580	}
52
53			@Override
54	torben	307	protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
55	torben	458	if (req.getParameter("station") == null) {
56			resp.sendError(400, "not enough parameters");
57			return;
58			}
59
60	torben	307	int station = Integer.parseInt( req.getParameter("station") );
61			String format = req.getParameter("format");
62
63			List<DepartureBean> beans;
64
65			String stationName = getStationName(station);
66
67			try {
68	torben	387	beans = fetcher.cachedLookupDepartures(station);
69	torben	462	} catch (java.io.IOException ioe) {
70			logger.warning("Read failed, station="+station + ". " + ioe.getMessage() );
71	torben	348	resp.sendError(500);
72			return;
73	torben	421	} catch (CircuitBreakerException cbe) {
74			logger.warning("Circuitbreaker - failing fast");
75			resp.sendError(500);
76			return;
77	torben	451	} catch (Exception e) {
78	torben	348	logger.log(Level.WARNING, "Unknown exception, station=" +station, e);
79			resp.sendError(500);
80			return;
81	torben	307	}
82
83			resp.setDateHeader("Expires", 0);
84			resp.setHeader("Cache-Control", "no-cache, must-revalidate");
85
86			if (format.equalsIgnoreCase("xml")) {
87			resp.setContentType("text/xml");
88			resp.getWriter().print( formatXml(beans, stationName) );
89			} else if (format.equalsIgnoreCase("html")) {
90	torben	585
91			String advStr = req.getParameter("advanced");
92			boolean advanced = advStr != null ? Boolean.parseBoolean(advStr) : false;
93
94			req.setAttribute("advanced", advanced);
95	torben	307	req.setAttribute("stationname", stationName );
96			req.setAttribute("departurebeans", beans);
97			req.setAttribute("stationID", station );
98			getServletContext().getRequestDispatcher("/ViewDepartures.jsp").forward(req,resp);
99			} else {
100			throw new ServletException("Unknown format");
101			}
102
103			}
104
105			protected String formatXml(List<DepartureBean> beans, String stationName) throws ServletException{
106			String xml = "";
107			try {
108			DocumentBuilder builder = docBuilderFactory.newDocumentBuilder();
109			DOMImplementation impl = builder.getDOMImplementation();
110
111
112			Document doc = impl.createDocument(null,null,null);
113			Element root = doc.createElement("departureinfo");
114			root.setAttribute("station", stationName);
115			for (DepartureBean departure : beans) {
116			Element train = doc.createElement("train");
117
118			Element time = doc.createElement("time");
119			time.setTextContent( departure.getTime() );
120			train.appendChild(time);
121
122			Element updated = doc.createElement("updated");
123			updated.setTextContent( String.valueOf(departure.getUpdated()) );
124			train.appendChild(updated);
125
126			Element trainNumber = doc.createElement("trainnumber");
127			trainNumber.setTextContent( departure.getTrainNumber() );
128			train.appendChild(trainNumber);
129
130			Element destination = doc.createElement("destination");
131			destination.setTextContent( departure.getDestination());
132			train.appendChild(destination);
133
134			Element origin = doc.createElement("origin");
135			origin.setTextContent( departure.getOrigin() );
136			train.appendChild(origin);
137
138			Element location= doc.createElement("location");
139			location.setTextContent( departure.getLocation() );
140			train.appendChild(location);
141
142			Element status = doc.createElement("status");
143			status.setTextContent( departure.getStatus() );
144			train.appendChild(status);
145
146			Element note = doc.createElement("note");
147			note.setTextContent( departure.getNote() );
148			train.appendChild(note);
149
150			root.appendChild(train);
151			}
152
153			doc.appendChild(root);
154
155
156			DOMSource domSource = new DOMSource(doc);
157
158			Transformer transformer = transformerFactory.newTransformer();
159			//transformer.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, "yes");
160			transformer.setOutputProperty(OutputKeys.METHOD, "xml");
161			transformer.setOutputProperty(OutputKeys.ENCODING,"ISO-8859-1");
162			transformer.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "4");
163			transformer.setOutputProperty(OutputKeys.INDENT, "yes");
164			java.io.StringWriter sw = new java.io.StringWriter();
165			StreamResult sr = new StreamResult(sw);
166			transformer.transform(domSource, sr);
167			xml = sw.toString();
168
169
170			} catch (Exception e) {
171			throw new ServletException(e);
172			}
173			return xml;
174			}
175
176			protected String getStationName(int stationID) {
177			String station = "";
178
179			Connection conn = null;
180			try {
181			conn = DBConnection.getConnection();
182			Statement stmt = conn.createStatement();
183			ResultSet rs = stmt.executeQuery("SELECT name FROM trainstations WHERE id=" + stationID);
184			if (rs.next()) {
185			station = rs.getString(1);
186			}
187
188			} catch (Exception e) {
189			} finally {
190			try {
191			if (conn != null && !conn.isClosed())
192			conn.close();
193			} catch (Exception e) {}
194			}
195
196			return station;
197			}
198
199			}