traininfoservice/db/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.ArrayList;
import java.util.List;

public class StationDAO {
        final static int LOCATION_LIMIT = 5;
        
        private StationBean convertSingleRow(ResultSet res) throws SQLException {
                StationBean station = new StationBean();

                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) );

                return station;
        }

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

        }


        public StationBean 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;
                StationBean 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 List<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 ";


                List<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 0.7 degrees latitude and 1.2 degrees longitude is only valid since we only service danish trains
        // in denmark 0.7dg latitude ~ 77km, 1.2dg longitude ~ 76km

        // 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 List<StationBean> getByLocationWorker(double latitude, double longitude, boolean geolimit) throws SQLException {
                
                String limitExpression = geolimit == true ? "AND abs(latitude-?)<0.7 AND abs(longitude-?)<1.2 " : "";
                
                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;


                List<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 List<StationBean> getByLocation(double latitude, double longitude) throws SQLException {
                List<StationBean> result = getByLocationWorker(latitude, longitude, true);
                
                if (result.size() < LOCATION_LIMIT) { //failover
                        result = getByLocationWorker(latitude, longitude, false);
                }
                
                return result;
        }
        
        
        public List<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;
                List<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 ";

                List<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.size() == 1) {
                        return result.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			import java.util.ArrayList;
9			import java.util.List;
10
11			public class StationDAO {
12	torben	841	final static int LOCATION_LIMIT = 5;
13
14	torben	588	private StationBean convertSingleRow(ResultSet res) throws SQLException {
15			StationBean station = new StationBean();
16	torben	836
17	torben	588	station.setId( res.getInt(1) );
18			station.setName( res.getString(2) );
19			station.setLatitude( res.getDouble(3) );
20			station.setLongitude( res.getDouble(4) );
21			station.setRegional( res.getString(5) );
22			station.setStrain( res.getString(6) );
23			station.setMetro( res.getString(7) );
24			station.setAddress( res.getString(8) );
25			station.setCalcdist( (int)res.getDouble(9) );
26	torben	836
27	torben	588	return station;
28			}
29	torben	836
30	torben	588	private List<StationBean> convertResultset(ResultSet res) throws SQLException {
31			List<StationBean> stations = new ArrayList<StationBean>();
32			while (res.next()) {
33			stations.add( convertSingleRow(res) );
34			}
35			return stations;
36	torben	836
37	torben	588	}
38	torben	836
39
40	torben	588	public StationBean getById(int id) throws SQLException {
41			String SQL = "SELECT id,name,latitude,longitude,stationcode_fjrn,stationcode_stog,stationcode_metro,address,0.0 " +
42	torben	836	"FROM trainstations WHERE id=" + id + " AND enabled=true";
43
44	torben	588	Connection conn = null;
45	torben	589	Statement stmt = null;
46			ResultSet res = null;
47	torben	588	StationBean result;
48	torben	836
49	torben	588	try {
50			conn = DBConnection.getConnection();
51	torben	836
52	torben	589	stmt = conn.createStatement();
53			res = stmt.executeQuery(SQL);
54	torben	588	res.next();
55			result = convertSingleRow(res);
56			} finally {
57	torben	589	if (res != null)
58			res.close();
59			if (stmt != null)
60			stmt.close();
61	torben	588	if (conn != null)
62			conn.close();
63			}
64	torben	836
65	torben	588	return result;
66			}
67	torben	836
68	torben	714	/*
69			* 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) )
70			* create function rlike(text,text) returns bool as
71			* 'select $2 ilike $1' language sql strict immutable;
72	torben	836	* create operator ~~~ (procedure = rlike, leftarg = text, rightarg = text, commutator = ~~);
73	torben	714	*/
74	torben	588	public List<StationBean> getByName(String name) throws SQLException {
75			String SQL = "SELECT id,name,latitude,longitude,stationcode_fjrn,stationcode_stog, stationcode_metro, address, 0.0 " +
76			"FROM trainstations " +
77	torben	714	"WHERE (name ILIKE ? OR ? ~~~ ANY(aliases)) AND enabled = true " +
78	torben	588	"ORDER BY name ";
79
80	torben	836
81	torben	588	List<StationBean> result;
82			Connection conn = null;
83	torben	589	PreparedStatement stmt = null;
84			ResultSet res = null;
85	torben	588	try {
86			conn = DBConnection.getConnection();
87	torben	589	stmt = conn.prepareStatement(SQL);
88	torben	836
89	torben	588	stmt.setString(1, name + "%");
90	torben	714	stmt.setString(2, name + "%");
91	torben	836
92	torben	589	res = stmt.executeQuery();
93			result = convertResultset(res);
94	torben	836
95	torben	588	} finally {
96	torben	589	if (res != null)
97			res.close();
98			if (stmt != null)
99			stmt.close();
100			if (conn!= null)
101	torben	588	conn.close();
102			}
103			return result;
104			}
105	torben	836
106	torben	849	//the "hack" with max 0.7 degrees latitude and 1.2 degrees longitude is only valid since we only service danish trains
107			// in denmark 0.7dg latitude ~ 77km, 1.2dg longitude ~ 76km
108	torben	836
109	torben	741	// the ultra fast method (and only slightly inaccurate as long as we only cover a limited geographically area)
110			// is using an aproximation of the length of 1 latitude degree and 1 longitude degree and just use pythagoras to
111			// calculate the distance:
112	torben	836	// sqrt( power(abs(latitude-?)111320, 2) + power(abs(longitude-?)63000,2) )::int as calcdist
113
114	torben	841	public List<StationBean> getByLocationWorker(double latitude, double longitude, boolean geolimit) throws SQLException {
115
116	torben	849	String limitExpression = geolimit == true ? "AND abs(latitude-?)<0.7 AND abs(longitude-?)<1.2 " : "";
117	torben	841
118			String SQL = "SELECT id,name,latitude,longitude,stationcode_fjrn,stationcode_stog, stationcode_metro, address, " +
119			"earth_distance( earth_coord, ll_to_earth(?,?))::int AS calcdist " +
120			"FROM trainstations " +
121			"WHERE enabled = true " + limitExpression +
122			"ORDER BY calcdist ASC " +
123			"LIMIT " + LOCATION_LIMIT;
124	torben	849
125
126	torben	841
127	torben	588	List<StationBean> result;
128			Connection conn = null;
129	torben	589	PreparedStatement stmt = null;
130			ResultSet res = null;
131	torben	588	try {
132			conn = DBConnection.getConnection();
133	torben	589	stmt = conn.prepareStatement(SQL);
134	torben	588	stmt.setDouble(1, latitude);
135			stmt.setDouble(2, longitude);
136	torben	841	if (geolimit == true) {
137			stmt.setDouble(3, latitude);
138			stmt.setDouble(4, longitude);
139			}
140	torben	589	res = stmt.executeQuery();
141			result = convertResultset(res);
142	torben	849
143	torben	588	} finally {
144	torben	589	if (res != null)
145			res.close();
146			if (stmt != null)
147			stmt.close();
148			if (conn!= null)
149	torben	588	conn.close();
150			}
151			return result;
152			}
153	torben	841
154			public List<StationBean> getByLocation(double latitude, double longitude) throws SQLException {
155			List<StationBean> result = getByLocationWorker(latitude, longitude, true);
156
157			if (result.size() < LOCATION_LIMIT) { //failover
158			result = getByLocationWorker(latitude, longitude, false);
159			}
160
161			return result;
162			}
163
164
165	torben	836
166			public List<StationBean> getByList(String list) throws SQLException {
167			String SQL = "SELECT id,name,latitude,longitude,stationcode_fjrn,stationcode_stog,stationcode_metro, address,0.0 " +
168			"FROM trainstations " +
169			"WHERE id IN " + list + " AND enabled = true " +
170			"ORDER BY name ";
171
172			Connection conn = null;
173			Statement stmt = null;
174			ResultSet res = null;
175			List<StationBean> result;
176
177			try {
178			conn = DBConnection.getConnection();
179			stmt = conn.createStatement();
180			res = stmt.executeQuery(SQL);
181			result = convertResultset(res);
182			} finally {
183			if (res != null)
184			res.close();
185			if (stmt != null)
186			stmt.close();
187			if (conn!= null)
188			conn.close();
189			}
190
191			return result;
192
193			}
194			public static String getStationName(int stationID) {
195			String station = "";
196
197			Connection conn = null;
198			try {
199			conn = DBConnection.getConnection();
200			Statement stmt = conn.createStatement();
201			ResultSet rs = stmt.executeQuery("SELECT name FROM trainstations WHERE id=" + stationID);
202			if (rs.next()) {
203			station = rs.getString(1);
204			}
205
206			} catch (Exception e) {
207			} finally {
208	torben	588	try {
209	torben	836	if (conn != null && !conn.isClosed())
210	torben	588	conn.close();
211	torben	836	} catch (Exception e) {}
212			}
213	torben	650
214	torben	836	return station;
215			}
216	torben	650
217	torben	842	public int getIdByName(String name) throws SQLException {
218	torben	836	String SQL = "SELECT id,name,latitude,longitude,stationcode_fjrn,stationcode_stog, stationcode_metro, address, 0.0 " +
219			"FROM trainstations " +
220			"WHERE name = ? AND enabled = true " +
221			"LIMIT 1 ";
222	torben	650
223	torben	836	List<StationBean> result;
224			Connection conn = null;
225			PreparedStatement stmt = null;
226			ResultSet res = null;
227			try {
228			conn = DBConnection.getConnection();
229			stmt = conn.prepareStatement(SQL);
230
231			stmt.setString(1, name );
232
233			res = stmt.executeQuery();
234			result = convertResultset(res);
235
236			} finally {
237			if (res != null)
238			res.close();
239			if (stmt != null)
240			stmt.close();
241			if (conn!= null)
242			conn.close();
243			}
244
245			if (result.size() == 1) {
246			return result.get(0).getId();
247			} else {
248			return -1;
249			}
250			}
251	torben	588	}