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1 package de.laures.cewolf.dp;
2
3 import java.io.Serializable  ;
4 import java.sql.Connection ;
5 import java.sql.ResultSet ;
6 import java.util.Map ;
7
8 import javax.naming.Context ;
9 import javax.naming.InitialContext ;
10 import javax.naming.NamingException ;
11 import javax.sql.DataSource ;
12
13 import org.jfree.data.xy.XYSeries;
14
15 import de.laures.cewolf.DatasetProduceException;
16
17
25 public class DataSourceXYSeries implements Serializable {
26
27 private String dataSourceName;
28 private String query;
29 private String xCol = "x";
30 private String yCol = "y";
31 private String seriesName = "name";
32
33
36 public DataSourceXYSeries(String dataSourceName, String query) {
37 this.dataSourceName = dataSourceName;
38 this.query = query;
39 }
40
41 protected DataSource getDataSource() throws NamingException {
42 Context initCtx = new InitialContext ();
43 Context envCtx = (Context ) initCtx.lookup("java:comp/env");
44 return (DataSource ) envCtx.lookup(dataSourceName);
45 }
46
47
50 public XYSeries produceXYSeries() throws DatasetProduceException {
51 XYSeries series = new XYSeries(seriesName);
52 try {
53 DataSource ds = getDataSource();
54 Connection con = ds.getConnection();
55 ResultSet rs = con.createStatement().executeQuery(query);
56 int xColIndex = rs.findColumn(xCol);
57 int yColIndex = rs.findColumn(yCol);
58 while(rs.next()){
59 series.add((Number )rs.getObject(xColIndex), (Number )rs.getObject(yColIndex));
60 }
61 } catch (Exception namingEx) {
62 namingEx.printStackTrace();
63 throw new DatasetProduceException(namingEx.getMessage());
64 }
65 return series;
66 }
67 }
68 |
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