Custom JRDataSource

package com.dbelectronics;

import net.sf.jasperreports.engine.JRDataSource;
import net.sf.jasperreports.engine.JRField;
import net.sf.jasperreports.engine.JRException;

/*
This example is a custom JRDataSource containing 3 fields:
    - "Banda" wich contains 20 strings (used as labels in the chart)
    - "Calibracion" wich will be created dinamically from a CSV field (like "48,50,53,49")
    - "Verificacion" same as the previous one
*/
public class BandasCSVDatasource implements JRDataSource {

    String[] labels = {"63","83","100","125","160","200","250","315","400","500","630","800",
            "1.0k","1.2k","1.6k","2.0k","2.5k","3.0k","4.0k","5.0k"};
    String[] calibracion;
    String[] verificacion;
    int index;

    public BandasCSVDatasource(String csv1, String csv2) {
        calibracion = csv1.split(",");
        verificacion = csv2.split(",");
        index = -1;
    }

    /* Optional method containing your field names */
    public static String[] fieldNames() {
        String[] fieldNames = {"Banda","Verificacion","Calibracion"};
        return fieldNames;
    }

    @Override
    public Object getFieldValue(JRField f) throws JRException {
        String fieldName = f.getName();
        Object o = null;

        if ( fieldName.equals("Banda") ) {
            o = labels[index];
        } else if ( fieldName.equals("Verificacion") ) {
            o = verificacion[index];
        } else {
            o = calibracion[index];
        }
        return o;
    }

    @Override
    public boolean next() throws JRException {
        index++;
        if (index>=20) {
            return false;
        } else {
            if (index<calibracion.length && index<verificacion.length) {
                return true;
            } else {
                return false;
            }
        }
    }
}