package de.laures.cewolf.dp;

 import java.io.Serializable;

 import java.sql.Connection;

 import java.sql.ResultSet;

 import java.util.Map;

 import javax.naming.Context;

 import javax.naming.InitialContext;

 import javax.naming.NamingException;

 import javax.sql.DataSource;

 import org.jfree.data.xy.XYSeries;

 import de.laures.cewolf.DatasetProduceException;

 /**

  * @author glaures

  *

  * To change this generated comment edit the template variable "typecomment":

  * Window>Preferences>Java>Templates.

  * To enable and disable the creation of type comments go to

  * Window>Preferences>Java>Code Generation.

  */

 public class DataSourceXYSeries implements Serializable {

 	private String dataSourceName;

 	private String query;

 	private String xCol = "x";

 	private String yCol = "y";

 	private String seriesName = "name";

 	/**

 	 * Constructor for DataSourceXYSeries.

 	 */

 	public DataSourceXYSeries(String dataSourceName, String query) {

 		this.dataSourceName = dataSourceName;

 		this.query = query;

 	}

 	protected DataSource getDataSource() throws NamingException {

 		Context initCtx = new InitialContext();

 		Context envCtx = (Context) initCtx.lookup("java:comp/env");

 		return (DataSource) envCtx.lookup(dataSourceName);

 	}

 	/**

 	 * @see de.laures.cewolf.DatasetProducer#produceDataset(Map)

 	 */

 	public XYSeries produceXYSeries() throws DatasetProduceException {

 		XYSeries series = new XYSeries(seriesName);

 		try {

 			DataSource ds = getDataSource();

 			Connection con = ds.getConnection();

 			ResultSet rs = con.createStatement().executeQuery(query);

 			int xColIndex = rs.findColumn(xCol);

 			int yColIndex = rs.findColumn(yCol);

 			while(rs.next()){

 				series.add((Number)rs.getObject(xColIndex), (Number)rs.getObject(yColIndex));

 			}

 		} catch (Exception namingEx) {

 			namingEx.printStackTrace();

 			throw new DatasetProduceException(namingEx.getMessage());

 		}

 		return series;

 	}

 }