traininfoservice/db/StationDAO.java

package dk.thoerup.traininfoservice.db;

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

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

public class StationDAO {
        
        private interface StatementParamSetter {
                public void setParams(PreparedStatement stmt) throws SQLException ;
        }
        private class NullSetter implements StatementParamSetter {
                @Override
                public void setParams(PreparedStatement stmt) throws SQLException {}
        }
        
        public static class NostationException extends Exception {
                private static final long serialVersionUID = 1L;
        }
        
        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;

        }

        private StationBean fetchStations(String SQL, StatementParamSetter setter) throws SQLException {
                StationBean stations;
                Connection conn = null;
                PreparedStatement stmt = null;
                ResultSet res = null;
                try {
                        conn = DBConnection.getConnection();
                        stmt = conn.prepareStatement(SQL);
                        
                        setter.setParams(stmt);

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

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

        public StationEntry getById(int id) throws SQLException,NostationException {
                String SQL = "SELECT id,name,latitude,longitude,stationcode_fjrn,stationcode_stog,stationcode_metro,address,0.0 " +
                "FROM trainstations WHERE id=" + id + " AND enabled=true";
                                
                StationBean stations =  fetchStations(SQL, new NullSetter() );
                
                if (stations.entries.size() > 0 ) {
                        return stations.entries.get(0);
                } else {
                        throw new NostationException();
                }
        }
        

        /*
         * 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 getByNameNormal(final 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 ";

                class NameSetter implements StatementParamSetter {
                        @Override
                        public void setParams(PreparedStatement stmt) throws SQLException {
                                stmt.setString(1, name + "%");
                                stmt.setString(2, name + "%");                          
                        }                       
                }
                
                return fetchStations(SQL, new NameSetter() );
        }
        
        
        public StationBean getByNameFuzzy(final String name) throws SQLException {
                String SQL = "SELECT * FROM (" +
                                         "    SELECT id,name,latitude,longitude,stationcode_fjrn,stationcode_stog, stationcode_metro, address, 0.0, " +
                                         "    levenshtein(lower(name),lower(?) ) as leven " +
                                         "    FROM trainstations " +
                                         "    WHERE  enabled = true ) as lev2 " +
                                         "WHERE (leven <= 3) " +                
                                         "ORDER BY leven " + 
                                         "LIMIT 1";

                class NameSetter implements StatementParamSetter {
                        @Override
                        public void setParams(PreparedStatement stmt) throws SQLException {
                                stmt.setString(1, name );
                        }                       
                }
                
                StationBean stations = fetchStations(SQL, new NameSetter() );
                stations.fuzzystrmatch = true;
                return stations;
        }
        
        private String removeSuffix(String str, String suffix) {
                if (str.endsWith(suffix)) {
                        return str.substring(0, str.length() - suffix.length() );
                } else {
                        return str;
                }
        }
        
        public StationBean getByName(String name) throws SQLException {
                name = removeSuffix(name, " st.");
                name = removeSuffix(name, " st");
                name = removeSuffix(name, " station");
                
                StationBean stations = getByNameNormal(name);
                
                if (stations.entries.size() == 0) {
                        stations = getByNameFuzzy(name);

                        logger.info("getByName failover: " + name + "(" + (stations.entries.size() >0) + ")" );
                }
                return stations;
        }
        
        
        //Latitude (horizonal), longitude(vertical) so
        // 1 degree latitude is ~ 111320 meters, since the distance between the horizonal lines is always the same 
        // 1 degree longitude is ~111320 meters at equator but gets shorter as we get closer to the poles.
        // so 1 degree longitude is 64.5 km at denmarks southern point (gedser=54.55,11.95)
        // and is 59.4km at northern point (skagen = 57.75,10.65)
        // 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(final double latitude, final double longitude, final 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;

                
                class LatlongSetter implements StatementParamSetter {
                        @Override
                        public void setParams(PreparedStatement stmt) throws SQLException {
                                stmt.setDouble(1, latitude);
                                stmt.setDouble(2, longitude);
                                if (geolimit == true) {
                                        stmt.setDouble(3, latitude);
                                        stmt.setDouble(4, longitude);
                                }                               
                        }                       
                }
                
                return fetchStations(SQL, new LatlongSetter() );
        }
        
        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 ";
                
                return fetchStations(SQL, new NullSetter() );
        }
        

        public StationEntry getSimpleByName(final 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 ";

                class NameSetter implements StatementParamSetter {
                        @Override
                        public void setParams(PreparedStatement stmt) throws SQLException {
                                stmt.setString(1, name );
                        }                       
                }
                
                StationBean stations = fetchStations(SQL, new NameSetter() );
                
                if (stations.entries.size() == 1) {
                        return stations.entries.get(0);
                } else {
                        return null;
                }
        }
        
        Comparator<StationEntry> nameComparator = new Comparator<StationEntry>() {
                @Override
                public int compare(StationEntry arg0, StationEntry arg1) {
                        return arg0.getName().compareTo( arg1.getName() );
                }               
        };
        
        //used to create full dump in order to populate Google Appengine DB
        //after 1.1.0 also used to populate client-side station list
        public StationBean dumpAll() throws SQLException {
                
                String SQL = "SELECT id,name,latitude,longitude,stationcode_fjrn,stationcode_stog,stationcode_metro,address,0.0,aliases " +
                                "FROM trainstations WHERE enabled = true";
                
                Connection conn = null;
                Statement stmt = null;
                ResultSet res = null;           

                
                try {
                        conn = DBConnection.getConnection();

                        stmt = conn.createStatement();
                        res = stmt.executeQuery(SQL);           
                                                
                        // Does mostly the same as convertResultset()
                        StationBean stations = new StationBean();
                        while (res.next()) {
                                StationEntry entry = convertSingleRow(res);
                                
                                Array arr = res.getArray(10);
                                if (arr != null) {
                                        String[] aliases = (String[]) arr.getArray();
                                        entry.setAliases(aliases);
                                }
                                
                                stations.entries.add( entry );
                                
                        }
                        Collections.sort( stations.entries,nameComparator );
                        return stations;
                        

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

        @Deprecated
        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;
        }
        
        
        @Deprecated
        public int getIdByName(final 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 ";

                class NameSetter implements StatementParamSetter {
                        @Override
                        public void setParams(PreparedStatement stmt) throws SQLException {
                                stmt.setString(1, name );
                        }                       
                }
                
                StationBean stations = fetchStations(SQL, new NameSetter() );
                
                if (stations.entries.size() == 1) {
                        return stations.entries.get(0).getId();
                } else {
                        return -1;
                }
        }
}
1	package dk.thoerup.traininfoservice.db;
2
3	import java.sql.Array;
4	import java.sql.Connection;
5	import java.sql.PreparedStatement;
6	import java.sql.ResultSet;
7	import java.sql.SQLException;
8	import java.sql.Statement;
9	import java.util.Collections;
10	import java.util.Comparator;
11	import java.util.logging.Logger;
12
13	import dk.thoerup.android.traininfo.common.StationBean;
14	import dk.thoerup.android.traininfo.common.StationEntry;
15
16	public class StationDAO {
17
18	private interface StatementParamSetter {
19	public void setParams(PreparedStatement stmt) throws SQLException ;
20	}
21	private class NullSetter implements StatementParamSetter {
22	@Override
23	public void setParams(PreparedStatement stmt) throws SQLException {}
24	}
25
26	public static class NostationException extends Exception {
27	private static final long serialVersionUID = 1L;
28	}
29
30	final static int LOCATION_LIMIT = 8;
31	static final Logger logger = Logger.getLogger(StationDAO.class.getName());
32
33
34	private StationEntry convertSingleRow(ResultSet res) throws SQLException {
35	StationEntry station = new StationEntry();
36
37	station.setId( res.getInt(1) );
38	station.setName( res.getString(2) );
39	station.setLatitude( res.getDouble(3) );
40	station.setLongitude( res.getDouble(4) );
41	station.setRegional( res.getString(5) );
42	station.setStrain( res.getString(6) );
43	station.setMetro( res.getString(7) );
44	station.setAddress( res.getString(8) );
45	station.setCalcdist( (int)res.getDouble(9) );
46
47	station.setIsRegional( station.getRegional() != null );
48	station.setIsStrain( station.getStrain() != null );
49	station.setIsMetro( station.getMetro() != null );
50
51	return station;
52	}
53
54	private StationBean convertResultset(ResultSet res) throws SQLException {
55	StationBean stations = new StationBean();
56	while (res.next()) {
57	stations.entries.add( convertSingleRow(res) );
58	}
59	return stations;
60
61	}
62
63	private StationBean fetchStations(String SQL, StatementParamSetter setter) throws SQLException {
64	StationBean stations;
65	Connection conn = null;
66	PreparedStatement stmt = null;
67	ResultSet res = null;
68	try {
69	conn = DBConnection.getConnection();
70	stmt = conn.prepareStatement(SQL);
71
72	setter.setParams(stmt);
73
74	res = stmt.executeQuery();
75	stations = convertResultset(res);
76
77	} finally {
78	if (res != null)
79	res.close();
80	if (stmt != null)
81	stmt.close();
82	if (conn!= null)
83	conn.close();
84	}
85	return stations;
86
87	}
88
89	public StationEntry getById(int id) throws SQLException,NostationException {
90	String SQL = "SELECT id,name,latitude,longitude,stationcode_fjrn,stationcode_stog,stationcode_metro,address,0.0 " +
91	"FROM trainstations WHERE id=" + id + " AND enabled=true";
92
93	StationBean stations = fetchStations(SQL, new NullSetter() );
94
95	if (stations.entries.size() > 0 ) {
96	return stations.entries.get(0);
97	} else {
98	throw new NostationException();
99	}
100	}
101
102
103
104	/*
105	* 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) )
106	* create function rlike(text,text) returns bool as
107	* 'select $2 ilike $1' language sql strict immutable;
108	* create operator ~~~ (procedure = rlike, leftarg = text, rightarg = text, commutator = ~~);
109	*/
110	public StationBean getByNameNormal(final String name) throws SQLException {
111	String SQL = "SELECT id,name,latitude,longitude,stationcode_fjrn,stationcode_stog, stationcode_metro, address, 0.0 " +
112	"FROM trainstations " +
113	"WHERE (name ILIKE ? OR ? ~~~ ANY(aliases)) AND enabled = true " +
114	"ORDER BY name ";
115
116	class NameSetter implements StatementParamSetter {
117	@Override
118	public void setParams(PreparedStatement stmt) throws SQLException {
119	stmt.setString(1, name + "%");
120	stmt.setString(2, name + "%");
121	}
122	}
123
124	return fetchStations(SQL, new NameSetter() );
125	}
126
127
128	public StationBean getByNameFuzzy(final String name) throws SQLException {
129	String SQL = "SELECT * FROM (" +
130	" SELECT id,name,latitude,longitude,stationcode_fjrn,stationcode_stog, stationcode_metro, address, 0.0, " +
131	" levenshtein(lower(name),lower(?) ) as leven " +
132	" FROM trainstations " +
133	" WHERE enabled = true ) as lev2 " +
134	"WHERE (leven <= 3) " +
135	"ORDER BY leven " +
136	"LIMIT 1";
137
138	class NameSetter implements StatementParamSetter {
139	@Override
140	public void setParams(PreparedStatement stmt) throws SQLException {
141	stmt.setString(1, name );
142	}
143	}
144
145	StationBean stations = fetchStations(SQL, new NameSetter() );
146	stations.fuzzystrmatch = true;
147	return stations;
148	}
149
150	private String removeSuffix(String str, String suffix) {
151	if (str.endsWith(suffix)) {
152	return str.substring(0, str.length() - suffix.length() );
153	} else {
154	return str;
155	}
156	}
157
158	public StationBean getByName(String name) throws SQLException {
159	name = removeSuffix(name, " st.");
160	name = removeSuffix(name, " st");
161	name = removeSuffix(name, " station");
162
163	StationBean stations = getByNameNormal(name);
164
165	if (stations.entries.size() == 0) {
166	stations = getByNameFuzzy(name);
167
168	logger.info("getByName failover: " + name + "(" + (stations.entries.size() >0) + ")" );
169	}
170	return stations;
171	}
172
173
174
175	//Latitude (horizonal), longitude(vertical) so
176	// 1 degree latitude is ~ 111320 meters, since the distance between the horizonal lines is always the same
177	// 1 degree longitude is ~111320 meters at equator but gets shorter as we get closer to the poles.
178	// so 1 degree longitude is 64.5 km at denmarks southern point (gedser=54.55,11.95)
179	// and is 59.4km at northern point (skagen = 57.75,10.65)
180	// The "hack" with max 0.4 degrees latitude and 0.75 degrees longitude is only valid since we only service danish trains,
181	// in denmark 0.4dg latitude ~ 44km, 0.75dg longitude ~ 47km
182
183	// the ultra fast method (and only slightly inaccurate as long as we only cover a limited geographically area)
184	// is using an aproximation of the length of 1 latitude degree and 1 longitude degree and just use pythagoras to
185	// calculate the distance:
186	// sqrt( power(abs(latitude-?)111320, 2) + power(abs(longitude-?)63000,2) )::int as calcdist
187
188	public StationBean getByLocationWorker(final double latitude, final double longitude, final boolean geolimit) throws SQLException {
189
190	String limitExpression = (geolimit == true) ? "AND abs(latitude-?)<0.4 AND abs(longitude-?)<0.75 " : "";
191
192	String SQL = "SELECT id,name,latitude,longitude,stationcode_fjrn,stationcode_stog, stationcode_metro, address, " +
193	"earth_distance( earth_coord, ll_to_earth(?,?))::int AS calcdist " +
194	"FROM trainstations " +
195	"WHERE enabled = true " + limitExpression +
196	"ORDER BY calcdist ASC " +
197	"LIMIT " + LOCATION_LIMIT;
198
199
200	class LatlongSetter implements StatementParamSetter {
201	@Override
202	public void setParams(PreparedStatement stmt) throws SQLException {
203	stmt.setDouble(1, latitude);
204	stmt.setDouble(2, longitude);
205	if (geolimit == true) {
206	stmt.setDouble(3, latitude);
207	stmt.setDouble(4, longitude);
208	}
209	}
210	}
211
212	return fetchStations(SQL, new LatlongSetter() );
213	}
214
215	public StationBean getByLocation(double latitude, double longitude) throws SQLException {
216	StationBean result = getByLocationWorker(latitude, longitude, true);
217
218	if (result.entries.size() < LOCATION_LIMIT) { //failover
219	logger.info("getByLocation failover: " +latitude + "," + longitude);
220
221	result = getByLocationWorker(latitude, longitude, false);
222	}
223
224	return result;
225	}
226
227
228
229	public StationBean getByList(String list) throws SQLException {
230	String SQL = "SELECT id,name,latitude,longitude,stationcode_fjrn,stationcode_stog,stationcode_metro, address,0.0 " +
231	"FROM trainstations " +
232	"WHERE id IN " + list + " AND enabled = true " +
233	"ORDER BY name ";
234
235	return fetchStations(SQL, new NullSetter() );
236	}
237
238
239
240	public StationEntry getSimpleByName(final String name) throws SQLException {
241	String SQL = "SELECT id,name,latitude,longitude,stationcode_fjrn,stationcode_stog, stationcode_metro, address, 0.0 " +
242	"FROM trainstations " +
243	"WHERE name = ? AND enabled = true " +
244	"LIMIT 1 ";
245
246	class NameSetter implements StatementParamSetter {
247	@Override
248	public void setParams(PreparedStatement stmt) throws SQLException {
249	stmt.setString(1, name );
250	}
251	}
252
253	StationBean stations = fetchStations(SQL, new NameSetter() );
254
255	if (stations.entries.size() == 1) {
256	return stations.entries.get(0);
257	} else {
258	return null;
259	}
260	}
261
262	Comparator<StationEntry> nameComparator = new Comparator<StationEntry>() {
263	@Override
264	public int compare(StationEntry arg0, StationEntry arg1) {
265	return arg0.getName().compareTo( arg1.getName() );
266	}
267	};
268
269	//used to create full dump in order to populate Google Appengine DB
270	//after 1.1.0 also used to populate client-side station list
271	public StationBean dumpAll() throws SQLException {
272
273	String SQL = "SELECT id,name,latitude,longitude,stationcode_fjrn,stationcode_stog,stationcode_metro,address,0.0,aliases " +
274	"FROM trainstations WHERE enabled = true";
275
276	Connection conn = null;
277	Statement stmt = null;
278	ResultSet res = null;
279
280
281	try {
282	conn = DBConnection.getConnection();
283
284	stmt = conn.createStatement();
285	res = stmt.executeQuery(SQL);
286
287	// Does mostly the same as convertResultset()
288	StationBean stations = new StationBean();
289	while (res.next()) {
290	StationEntry entry = convertSingleRow(res);
291
292	Array arr = res.getArray(10);
293	if (arr != null) {
294	String[] aliases = (String[]) arr.getArray();
295	entry.setAliases(aliases);
296	}
297
298	stations.entries.add( entry );
299
300	}
301	Collections.sort( stations.entries,nameComparator );
302	return stations;
303
304
305	} finally {
306	if (res != null)
307	res.close();
308	if (stmt != null)
309	stmt.close();
310	if (conn != null)
311	conn.close();
312	}
313
314	}
315
316	@Deprecated
317	public static String getStationName(int stationID) {
318	String station = "";
319
320	Connection conn = null;
321	try {
322	conn = DBConnection.getConnection();
323	Statement stmt = conn.createStatement();
324	ResultSet rs = stmt.executeQuery("SELECT name FROM trainstations WHERE id=" + stationID);
325	if (rs.next()) {
326	station = rs.getString(1);
327	}
328
329	} catch (Exception e) {
330	} finally {
331	try {
332	if (conn != null && !conn.isClosed())
333	conn.close();
334	} catch (Exception e) {}
335	}
336
337	return station;
338	}
339
340
341
342	@Deprecated
343	public int getIdByName(final String name) throws SQLException {
344	String SQL = "SELECT id,name,latitude,longitude,stationcode_fjrn,stationcode_stog, stationcode_metro, address, 0.0 " +
345	"FROM trainstations " +
346	"WHERE name = ? AND enabled = true " +
347	"LIMIT 1 ";
348
349	class NameSetter implements StatementParamSetter {
350	@Override
351	public void setParams(PreparedStatement stmt) throws SQLException {
352	stmt.setString(1, name );
353	}
354	}
355
356	StationBean stations = fetchStations(SQL, new NameSetter() );
357
358	if (stations.entries.size() == 1) {
359	return stations.entries.get(0).getId();
360	} else {
361	return -1;
362	}
363	}
364	}