thoerup/traininfoservice/StationDAO.java

package dk.thoerup.traininfoservice;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.logging.Logger;

import dk.thoerup.android.traininfo.common.StationBean;
import dk.thoerup.android.traininfo.common.StationBean.StationEntry;

public class StationDAO {
        final static int LOCATION_LIMIT = 8;
        static final Logger logger = Logger.getLogger(StationDAO.class.getName());
        
        
        private StationEntry convertSingleRow(ResultSet res) throws SQLException {
                StationEntry station = new StationEntry();

                station.setId( res.getInt(1) );
                station.setName( res.getString(2) );
                station.setLatitude( res.getDouble(3) );
                station.setLongitude( res.getDouble(4) );
                station.setRegional( res.getString(5) );
                station.setStrain( res.getString(6) );
                station.setMetro( res.getString(7) );
                station.setAddress( res.getString(8) );
                station.setCalcdist( (int)res.getDouble(9) );
                
                station.setIsRegional( station.getRegional() != null );
                station.setIsStrain( station.getStrain() != null );
                station.setIsMetro( station.getMetro() != null );

                return station;
        }

        private StationBean convertResultset(ResultSet res) throws SQLException {
                StationBean stations = new StationBean();
                while (res.next()) {
                        stations.entries.add( convertSingleRow(res) );
                }
                return stations;

        }


        public StationEntry getById(int id) throws SQLException {
                String SQL = "SELECT id,name,latitude,longitude,stationcode_fjrn,stationcode_stog,stationcode_metro,address,0.0 " +
                "FROM trainstations WHERE id=" + id + " AND enabled=true";

                Connection conn = null;
                Statement stmt = null;
                ResultSet res = null;
                StationEntry result;

                try {
                        conn = DBConnection.getConnection();

                        stmt = conn.createStatement();
                        res = stmt.executeQuery(SQL);           
                        res.next();
                        result = convertSingleRow(res);
                } finally {
                        if (res != null)
                                res.close();
                        if (stmt != null)
                                stmt.close();
                        if (conn != null)
                                conn.close();
                }

                return result;
        }

        /*
         * this code requires theses statements are run on database in order to do ILIKE searches against aliases (which is defines as array of varchar(64) )
         *     create function rlike(text,text) returns bool as 
         *     'select $2 ilike $1' language sql strict immutable;
         *     create operator ~~~ (procedure = rlike, leftarg = text, rightarg = text, commutator = ~~);
         */
        public StationBean getByName(String name) throws SQLException {
                String SQL = "SELECT id,name,latitude,longitude,stationcode_fjrn,stationcode_stog, stationcode_metro, address, 0.0 " + 
                "FROM trainstations " + 
                "WHERE (name ILIKE ? OR ? ~~~ ANY(aliases)) AND enabled = true " +
                "ORDER BY name ";


                StationBean result;
                Connection conn = null;
                PreparedStatement stmt = null;
                ResultSet res = null;
                try {
                        conn = DBConnection.getConnection();
                        stmt = conn.prepareStatement(SQL);

                        stmt.setString(1, name + "%");
                        stmt.setString(2, name + "%");

                        res = stmt.executeQuery();
                        result = convertResultset(res);

                } finally {
                        if (res != null)
                                res.close();
                        if (stmt != null)
                                stmt.close();
                        if (conn!= null)
                                conn.close();
                }
                return result;
        }

        //the "hack" with max 0.4 degrees latitude and 0.75 degrees longitude is only valid since we only service danish trains,
        // in denmark 0.4dg latitude ~ 44km, 0.75dg longitude ~ 47km

        // the ultra fast method  (and only slightly inaccurate as long as we only cover a limited geographically area)
        // is using an aproximation of the length of 1 latitude degree and 1 longitude degree and just use pythagoras to 
        // calculate the distance:
        //     sqrt( power(abs(latitude-?)*111320, 2) + power(abs(longitude-?)*63000,2) )::int as calcdist 

        public StationBean getByLocationWorker(double latitude, double longitude, boolean geolimit) throws SQLException {
                
                String limitExpression = (geolimit == true) ? "AND abs(latitude-?)<0.4 AND abs(longitude-?)<0.75 " : "";
                
                String SQL = "SELECT id,name,latitude,longitude,stationcode_fjrn,stationcode_stog, stationcode_metro, address, " + 
                        "earth_distance( earth_coord, ll_to_earth(?,?))::int AS calcdist " + 
                        "FROM trainstations " +
                        "WHERE enabled = true " + limitExpression +
                        "ORDER BY calcdist ASC " + 
                        "LIMIT " + LOCATION_LIMIT;


                StationBean result;
                Connection conn = null;
                PreparedStatement stmt = null;
                ResultSet res = null;
                try {
                        conn = DBConnection.getConnection();
                        stmt = conn.prepareStatement(SQL);
                        stmt.setDouble(1, latitude);
                        stmt.setDouble(2, longitude);
                        if (geolimit == true) {
                                stmt.setDouble(3, latitude);
                                stmt.setDouble(4, longitude);
                        }
                        res = stmt.executeQuery();
                        result = convertResultset(res);
                
                } finally {
                        if (res != null)
                                res.close();
                        if (stmt != null)
                                stmt.close();
                        if (conn!= null)
                                conn.close();
                }
                return result;
        }
        
        public StationBean getByLocation(double latitude, double longitude) throws SQLException {
                StationBean result = getByLocationWorker(latitude, longitude, true);
                
                if (result.entries.size() < LOCATION_LIMIT) { //failover
                        logger.info("getByLocation failover: " +latitude + "," + longitude);
                        
                        result = getByLocationWorker(latitude, longitude, false);
                }
                
                return result;
        }
        
        
        public StationBean getByList(String list) throws SQLException {
                String SQL = "SELECT id,name,latitude,longitude,stationcode_fjrn,stationcode_stog,stationcode_metro, address,0.0 " + 
                "FROM trainstations " + 
                "WHERE id IN " + list + " AND enabled = true " +
                "ORDER BY name ";

                Connection conn = null;
                Statement stmt = null;
                ResultSet res = null;
                StationBean result;

                try {
                        conn = DBConnection.getConnection();
                        stmt = conn.createStatement();
                        res = stmt.executeQuery(SQL);
                        result = convertResultset(res);
                } finally {
                        if (res != null)
                                res.close();
                        if (stmt != null)
                                stmt.close();
                        if (conn!= null)
                                conn.close();
                }

                return result;

        }
        public static 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;
        }

        public int getIdByName(String name) throws SQLException {
                String SQL = "SELECT id,name,latitude,longitude,stationcode_fjrn,stationcode_stog, stationcode_metro, address, 0.0 " + 
                "FROM trainstations " + 
                "WHERE name = ?  AND enabled = true " +
                "LIMIT 1 ";

                StationBean result;
                Connection conn = null;
                PreparedStatement stmt = null;
                ResultSet res = null;
                try {
                        conn = DBConnection.getConnection();
                        stmt = conn.prepareStatement(SQL);

                        stmt.setString(1, name );

                        res = stmt.executeQuery();
                        result = convertResultset(res);

                } finally {
                        if (res != null)
                                res.close();
                        if (stmt != null)
                                stmt.close();
                        if (conn!= null)
                                conn.close();
                }

                if (result.entries.size() == 1) {
                        return result.entries.get(0).getId();
                } else {
                        return -1;
                }
        }
}
1	torben	588	package dk.thoerup.traininfoservice;
2
3			import java.sql.Connection;
4			import java.sql.PreparedStatement;
5			import java.sql.ResultSet;
6			import java.sql.SQLException;
7			import java.sql.Statement;
8	torben	895	import java.util.logging.Logger;
9	torben	588
10	torben	1061	import dk.thoerup.android.traininfo.common.StationBean;
11			import dk.thoerup.android.traininfo.common.StationBean.StationEntry;
12	torben	1060
13	torben	588	public class StationDAO {
14	torben	997	final static int LOCATION_LIMIT = 8;
15	torben	895	static final Logger logger = Logger.getLogger(StationDAO.class.getName());
16	torben	841
17	torben	895
18	torben	1060	private StationEntry convertSingleRow(ResultSet res) throws SQLException {
19			StationEntry station = new StationEntry();
20	torben	836
21	torben	588	station.setId( res.getInt(1) );
22			station.setName( res.getString(2) );
23			station.setLatitude( res.getDouble(3) );
24			station.setLongitude( res.getDouble(4) );
25			station.setRegional( res.getString(5) );
26			station.setStrain( res.getString(6) );
27			station.setMetro( res.getString(7) );
28			station.setAddress( res.getString(8) );
29			station.setCalcdist( (int)res.getDouble(9) );
30	torben	1060
31			station.setIsRegional( station.getRegional() != null );
32			station.setIsStrain( station.getStrain() != null );
33			station.setIsMetro( station.getMetro() != null );
34	torben	836
35	torben	588	return station;
36			}
37	torben	836
38	torben	1060	private StationBean convertResultset(ResultSet res) throws SQLException {
39			StationBean stations = new StationBean();
40	torben	588	while (res.next()) {
41	torben	1060	stations.entries.add( convertSingleRow(res) );
42	torben	588	}
43			return stations;
44	torben	836
45	torben	588	}
46	torben	836
47
48	torben	1060	public StationEntry getById(int id) throws SQLException {
49	torben	588	String SQL = "SELECT id,name,latitude,longitude,stationcode_fjrn,stationcode_stog,stationcode_metro,address,0.0 " +
50	torben	836	"FROM trainstations WHERE id=" + id + " AND enabled=true";
51
52	torben	588	Connection conn = null;
53	torben	589	Statement stmt = null;
54			ResultSet res = null;
55	torben	1060	StationEntry result;
56	torben	836
57	torben	588	try {
58			conn = DBConnection.getConnection();
59	torben	836
60	torben	589	stmt = conn.createStatement();
61			res = stmt.executeQuery(SQL);
62	torben	588	res.next();
63			result = convertSingleRow(res);
64			} finally {
65	torben	589	if (res != null)
66			res.close();
67			if (stmt != null)
68			stmt.close();
69	torben	588	if (conn != null)
70			conn.close();
71			}
72	torben	836
73	torben	588	return result;
74			}
75	torben	836
76	torben	714	/*
77			* this code requires theses statements are run on database in order to do ILIKE searches against aliases (which is defines as array of varchar(64) )
78			* create function rlike(text,text) returns bool as
79			* 'select $2 ilike $1' language sql strict immutable;
80	torben	836	* create operator ~~~ (procedure = rlike, leftarg = text, rightarg = text, commutator = ~~);
81	torben	714	*/
82	torben	1060	public StationBean getByName(String name) throws SQLException {
83	torben	588	String SQL = "SELECT id,name,latitude,longitude,stationcode_fjrn,stationcode_stog, stationcode_metro, address, 0.0 " +
84			"FROM trainstations " +
85	torben	714	"WHERE (name ILIKE ? OR ? ~~~ ANY(aliases)) AND enabled = true " +
86	torben	588	"ORDER BY name ";
87
88	torben	836
89	torben	1060	StationBean result;
90	torben	588	Connection conn = null;
91	torben	589	PreparedStatement stmt = null;
92			ResultSet res = null;
93	torben	588	try {
94			conn = DBConnection.getConnection();
95	torben	589	stmt = conn.prepareStatement(SQL);
96	torben	836
97	torben	588	stmt.setString(1, name + "%");
98	torben	714	stmt.setString(2, name + "%");
99	torben	836
100	torben	589	res = stmt.executeQuery();
101			result = convertResultset(res);
102	torben	836
103	torben	588	} finally {
104	torben	589	if (res != null)
105			res.close();
106			if (stmt != null)
107			stmt.close();
108			if (conn!= null)
109	torben	588	conn.close();
110			}
111			return result;
112			}
113	torben	836
114	torben	928	//the "hack" with max 0.4 degrees latitude and 0.75 degrees longitude is only valid since we only service danish trains,
115			// in denmark 0.4dg latitude ~ 44km, 0.75dg longitude ~ 47km
116	torben	836
117	torben	741	// the ultra fast method (and only slightly inaccurate as long as we only cover a limited geographically area)
118			// is using an aproximation of the length of 1 latitude degree and 1 longitude degree and just use pythagoras to
119			// calculate the distance:
120	torben	836	// sqrt( power(abs(latitude-?)111320, 2) + power(abs(longitude-?)63000,2) )::int as calcdist
121
122	torben	1060	public StationBean getByLocationWorker(double latitude, double longitude, boolean geolimit) throws SQLException {
123	torben	841
124	torben	929	String limitExpression = (geolimit == true) ? "AND abs(latitude-?)<0.4 AND abs(longitude-?)<0.75 " : "";
125	torben	841
126			String SQL = "SELECT id,name,latitude,longitude,stationcode_fjrn,stationcode_stog, stationcode_metro, address, " +
127			"earth_distance( earth_coord, ll_to_earth(?,?))::int AS calcdist " +
128			"FROM trainstations " +
129			"WHERE enabled = true " + limitExpression +
130			"ORDER BY calcdist ASC " +
131			"LIMIT " + LOCATION_LIMIT;
132	torben	849
133
134	torben	841
135	torben	1060	StationBean result;
136	torben	588	Connection conn = null;
137	torben	589	PreparedStatement stmt = null;
138			ResultSet res = null;
139	torben	588	try {
140			conn = DBConnection.getConnection();
141	torben	589	stmt = conn.prepareStatement(SQL);
142	torben	588	stmt.setDouble(1, latitude);
143			stmt.setDouble(2, longitude);
144	torben	841	if (geolimit == true) {
145			stmt.setDouble(3, latitude);
146			stmt.setDouble(4, longitude);
147			}
148	torben	589	res = stmt.executeQuery();
149			result = convertResultset(res);
150	torben	849
151	torben	588	} finally {
152	torben	589	if (res != null)
153			res.close();
154			if (stmt != null)
155			stmt.close();
156			if (conn!= null)
157	torben	588	conn.close();
158			}
159			return result;
160			}
161	torben	841
162	torben	1060	public StationBean getByLocation(double latitude, double longitude) throws SQLException {
163			StationBean result = getByLocationWorker(latitude, longitude, true);
164	torben	841
165	torben	1060	if (result.entries.size() < LOCATION_LIMIT) { //failover
166	torben	894	logger.info("getByLocation failover: " +latitude + "," + longitude);
167
168	torben	841	result = getByLocationWorker(latitude, longitude, false);
169			}
170
171			return result;
172			}
173
174
175	torben	836
176	torben	1060	public StationBean getByList(String list) throws SQLException {
177	torben	836	String SQL = "SELECT id,name,latitude,longitude,stationcode_fjrn,stationcode_stog,stationcode_metro, address,0.0 " +
178			"FROM trainstations " +
179			"WHERE id IN " + list + " AND enabled = true " +
180			"ORDER BY name ";
181
182			Connection conn = null;
183			Statement stmt = null;
184			ResultSet res = null;
185	torben	1060	StationBean result;
186	torben	836
187			try {
188			conn = DBConnection.getConnection();
189			stmt = conn.createStatement();
190			res = stmt.executeQuery(SQL);
191			result = convertResultset(res);
192			} finally {
193			if (res != null)
194			res.close();
195			if (stmt != null)
196			stmt.close();
197			if (conn!= null)
198			conn.close();
199			}
200
201			return result;
202
203			}
204			public static String getStationName(int stationID) {
205			String station = "";
206
207			Connection conn = null;
208			try {
209			conn = DBConnection.getConnection();
210			Statement stmt = conn.createStatement();
211			ResultSet rs = stmt.executeQuery("SELECT name FROM trainstations WHERE id=" + stationID);
212			if (rs.next()) {
213			station = rs.getString(1);
214			}
215
216			} catch (Exception e) {
217			} finally {
218	torben	588	try {
219	torben	836	if (conn != null && !conn.isClosed())
220	torben	588	conn.close();
221	torben	836	} catch (Exception e) {}
222			}
223	torben	650
224	torben	836	return station;
225			}
226	torben	650
227	torben	842	public int getIdByName(String name) throws SQLException {
228	torben	836	String SQL = "SELECT id,name,latitude,longitude,stationcode_fjrn,stationcode_stog, stationcode_metro, address, 0.0 " +
229			"FROM trainstations " +
230			"WHERE name = ? AND enabled = true " +
231			"LIMIT 1 ";
232	torben	650
233	torben	1060	StationBean result;
234	torben	836	Connection conn = null;
235			PreparedStatement stmt = null;
236			ResultSet res = null;
237			try {
238			conn = DBConnection.getConnection();
239			stmt = conn.prepareStatement(SQL);
240
241			stmt.setString(1, name );
242
243			res = stmt.executeQuery();
244			result = convertResultset(res);
245
246			} finally {
247			if (res != null)
248			res.close();
249			if (stmt != null)
250			stmt.close();
251			if (conn!= null)
252			conn.close();
253			}
254
255	torben	1060	if (result.entries.size() == 1) {
256			return result.entries.get(0).getId();
257	torben	836	} else {
258			return -1;
259			}
260			}
261	torben	588	}