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 javax.jdo.PersistenceManager;

import dk.thoerup.android.traininfo.common.StationBean;
import dk.thoerup.android.traininfo.common.StationBean.StationEntry;
import dk.thoerup.traininfoservice.jdo.JdoStationBean;
import dk.thoerup.traininfoservice.jdo.PMF;

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 JdoStationBean getById(int id) throws SQLException {

                PersistenceManager pm = null;
                
                try {
                        pm = PMF.get().getPersistenceManager();
                        return pm.getObjectById(JdoStationBean.class, new Integer(id) );
                } finally {
                        pm.close();
                }
        }

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