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.ArrayList;
import java.util.List;

import com.sun.istack.logging.Logger;

public class StationDAO {
        final static int LOCATION_LIMIT = 5;
        static final Logger logger = Logger.getLogger(StationDAO.class);
        
        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 0.5 degrees latitude and 0.9 degrees longitude is only valid since we only service danish trains,
        // in denmark 0.5dg latitude ~ 55km, 0.9dg longitude ~ 57km

        // 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-?)<0.5 AND abs(longitude-?)<0.9 " : "";
                
                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
                        logger.info("getByLocation failover: " +latitude + "," + longitude);
                        
                        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	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	import com.sun.istack.logging.Logger;
12
13	public class StationDAO {
14	final static int LOCATION_LIMIT = 5;
15	static final Logger logger = Logger.getLogger(StationDAO.class);
16
17	private StationBean convertSingleRow(ResultSet res) throws SQLException {
18	StationBean station = new StationBean();
19
20	station.setId( res.getInt(1) );
21	station.setName( res.getString(2) );
22	station.setLatitude( res.getDouble(3) );
23	station.setLongitude( res.getDouble(4) );
24	station.setRegional( res.getString(5) );
25	station.setStrain( res.getString(6) );
26	station.setMetro( res.getString(7) );
27	station.setAddress( res.getString(8) );
28	station.setCalcdist( (int)res.getDouble(9) );
29
30	return station;
31	}
32
33	private List<StationBean> convertResultset(ResultSet res) throws SQLException {
34	List<StationBean> stations = new ArrayList<StationBean>();
35	while (res.next()) {
36	stations.add( convertSingleRow(res) );
37	}
38	return stations;
39
40	}
41
42
43	public StationBean getById(int id) throws SQLException {
44	String SQL = "SELECT id,name,latitude,longitude,stationcode_fjrn,stationcode_stog,stationcode_metro,address,0.0 " +
45	"FROM trainstations WHERE id=" + id + " AND enabled=true";
46
47	Connection conn = null;
48	Statement stmt = null;
49	ResultSet res = null;
50	StationBean result;
51
52	try {
53	conn = DBConnection.getConnection();
54
55	stmt = conn.createStatement();
56	res = stmt.executeQuery(SQL);
57	res.next();
58	result = convertSingleRow(res);
59	} finally {
60	if (res != null)
61	res.close();
62	if (stmt != null)
63	stmt.close();
64	if (conn != null)
65	conn.close();
66	}
67
68	return result;
69	}
70
71	/*
72	* 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) )
73	* create function rlike(text,text) returns bool as
74	* 'select $2 ilike $1' language sql strict immutable;
75	* create operator ~~~ (procedure = rlike, leftarg = text, rightarg = text, commutator = ~~);
76	*/
77	public List<StationBean> getByName(String name) throws SQLException {
78	String SQL = "SELECT id,name,latitude,longitude,stationcode_fjrn,stationcode_stog, stationcode_metro, address, 0.0 " +
79	"FROM trainstations " +
80	"WHERE (name ILIKE ? OR ? ~~~ ANY(aliases)) AND enabled = true " +
81	"ORDER BY name ";
82
83
84	List<StationBean> result;
85	Connection conn = null;
86	PreparedStatement stmt = null;
87	ResultSet res = null;
88	try {
89	conn = DBConnection.getConnection();
90	stmt = conn.prepareStatement(SQL);
91
92	stmt.setString(1, name + "%");
93	stmt.setString(2, name + "%");
94
95	res = stmt.executeQuery();
96	result = convertResultset(res);
97
98	} finally {
99	if (res != null)
100	res.close();
101	if (stmt != null)
102	stmt.close();
103	if (conn!= null)
104	conn.close();
105	}
106	return result;
107	}
108
109	//the "hack" with max 0.5 degrees latitude and 0.9 degrees longitude is only valid since we only service danish trains,
110	// in denmark 0.5dg latitude ~ 55km, 0.9dg longitude ~ 57km
111
112	// the ultra fast method (and only slightly inaccurate as long as we only cover a limited geographically area)
113	// is using an aproximation of the length of 1 latitude degree and 1 longitude degree and just use pythagoras to
114	// calculate the distance:
115	// sqrt( power(abs(latitude-?)111320, 2) + power(abs(longitude-?)63000,2) )::int as calcdist
116
117	public List<StationBean> getByLocationWorker(double latitude, double longitude, boolean geolimit) throws SQLException {
118
119	String limitExpression = geolimit == true ? "AND abs(latitude-?)<0.5 AND abs(longitude-?)<0.9 " : "";
120
121	String SQL = "SELECT id,name,latitude,longitude,stationcode_fjrn,stationcode_stog, stationcode_metro, address, " +
122	"earth_distance( earth_coord, ll_to_earth(?,?))::int AS calcdist " +
123	"FROM trainstations " +
124	"WHERE enabled = true " + limitExpression +
125	"ORDER BY calcdist ASC " +
126	"LIMIT " + LOCATION_LIMIT;
127
128
129
130	List<StationBean> result;
131	Connection conn = null;
132	PreparedStatement stmt = null;
133	ResultSet res = null;
134	try {
135	conn = DBConnection.getConnection();
136	stmt = conn.prepareStatement(SQL);
137	stmt.setDouble(1, latitude);
138	stmt.setDouble(2, longitude);
139	if (geolimit == true) {
140	stmt.setDouble(3, latitude);
141	stmt.setDouble(4, longitude);
142	}
143	res = stmt.executeQuery();
144	result = convertResultset(res);
145
146	} finally {
147	if (res != null)
148	res.close();
149	if (stmt != null)
150	stmt.close();
151	if (conn!= null)
152	conn.close();
153	}
154	return result;
155	}
156
157	public List<StationBean> getByLocation(double latitude, double longitude) throws SQLException {
158	List<StationBean> result = getByLocationWorker(latitude, longitude, true);
159
160	if (result.size() < LOCATION_LIMIT) { //failover
161	logger.info("getByLocation failover: " +latitude + "," + longitude);
162
163	result = getByLocationWorker(latitude, longitude, false);
164	}
165
166	return result;
167	}
168
169
170
171	public List<StationBean> getByList(String list) throws SQLException {
172	String SQL = "SELECT id,name,latitude,longitude,stationcode_fjrn,stationcode_stog,stationcode_metro, address,0.0 " +
173	"FROM trainstations " +
174	"WHERE id IN " + list + " AND enabled = true " +
175	"ORDER BY name ";
176
177	Connection conn = null;
178	Statement stmt = null;
179	ResultSet res = null;
180	List<StationBean> result;
181
182	try {
183	conn = DBConnection.getConnection();
184	stmt = conn.createStatement();
185	res = stmt.executeQuery(SQL);
186	result = convertResultset(res);
187	} finally {
188	if (res != null)
189	res.close();
190	if (stmt != null)
191	stmt.close();
192	if (conn!= null)
193	conn.close();
194	}
195
196	return result;
197
198	}
199	public static String getStationName(int stationID) {
200	String station = "";
201
202	Connection conn = null;
203	try {
204	conn = DBConnection.getConnection();
205	Statement stmt = conn.createStatement();
206	ResultSet rs = stmt.executeQuery("SELECT name FROM trainstations WHERE id=" + stationID);
207	if (rs.next()) {
208	station = rs.getString(1);
209	}
210
211	} catch (Exception e) {
212	} finally {
213	try {
214	if (conn != null && !conn.isClosed())
215	conn.close();
216	} catch (Exception e) {}
217	}
218
219	return station;
220	}
221
222	public int getIdByName(String name) throws SQLException {
223	String SQL = "SELECT id,name,latitude,longitude,stationcode_fjrn,stationcode_stog, stationcode_metro, address, 0.0 " +
224	"FROM trainstations " +
225	"WHERE name = ? AND enabled = true " +
226	"LIMIT 1 ";
227
228	List<StationBean> result;
229	Connection conn = null;
230	PreparedStatement stmt = null;
231	ResultSet res = null;
232	try {
233	conn = DBConnection.getConnection();
234	stmt = conn.prepareStatement(SQL);
235
236	stmt.setString(1, name );
237
238	res = stmt.executeQuery();
239	result = convertResultset(res);
240
241	} finally {
242	if (res != null)
243	res.close();
244	if (stmt != null)
245	stmt.close();
246	if (conn!= null)
247	conn.close();
248	}
249
250	if (result.size() == 1) {
251	return result.get(0).getId();
252	} else {
253	return -1;
254	}
255	}
256	}