(JfreeChart ) Linha vertical tem como colocar uma igual tem a linha horizontal branca tracejada ?

package erp.main;

import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;

import org.jfree.chart.ChartFactory;
import org.jfree.chart.JFreeChart;
import org.jfree.chart.axis.NumberAxis;
import org.jfree.chart.plot.CategoryPlot;
import org.jfree.chart.plot.PlotOrientation;
import org.jfree.chart.renderer.category.LineAndShapeRenderer;
import org.jfree.data.category.CategoryDataset;
import org.jfree.data.category.DefaultCategoryDataset;

import com.itextpdf.text.Document;
import com.itextpdf.text.DocumentException;
import com.itextpdf.text.Image;
import com.itextpdf.text.PageSize;
import com.itextpdf.text.pdf.PdfWriter;

public class Grafico {

	final JFreeChart chart;

	public Grafico() {
		final CategoryDataset dataset = createDataset();
    chart = createChart(dataset);
   
}

	public static void main(String[] args) throws FileNotFoundException, DocumentException, IOException {
		(new Grafico()).create(new FileOutputStream(new File("ugly-demo.pdf")));
	}

	/**
	 * Creates PDf file.
	 *
	 * @param outputStream {@link OutputStream}.
	 * @throws DocumentException
	 * @throws IOException
	 */
	public void create(OutputStream outputStream) throws DocumentException, IOException {
		Document document = null;
		PdfWriter writer = null;

		try {
			// instantiate document and writer
			document = new Document(PageSize.A4.rotate(),10f,10f,10f,10f);
			writer = PdfWriter.getInstance(document, outputStream);

			// open document
			document.open();

			// add image
			int width = 660;
			int height = 480;

			BufferedImage bufferedImage = chart.createBufferedImage(width, height);
			Image image = Image.getInstance(writer, bufferedImage, 1.0f);
			document.add(image);

			// release resources
			document.close();
			document = null;

			writer.close();
			writer = null;
		} catch (DocumentException de) {
			throw de;
		} catch (IOException ioe) {
			throw ioe;
		} finally {
			// release resources
			if (null != document) {
				try {
					document.close();
				} catch (Exception ex) {
				}
			}

			if (null != writer) {
				try {
					writer.close();
				} catch (Exception ex) {
				}
			}
		}
	}

	 /**
 * Creates a sample dataset.
 * 
 * @return The dataset.
 */
private CategoryDataset createDataset() {
    
    // row keys...
    final String series1 = "Arroz";
    final String series2 = "Feijão";
    final String series3 = "Macarrão";

    // column keys...
    final String type1 = "Janeiro";
    final String type2 = "Fevereiro";
    final String type3 = "Março";
    final String type4 = "Abril";
    final String type5 = "Maio";
    final String type6 = "Junho";
    final String type7 = "Julho";
    final String type8 = "Agosto";

    // create the dataset...
    final DefaultCategoryDataset dataset = new DefaultCategoryDataset();

    dataset.addValue(1.0, series1, type1);
    dataset.addValue(4.0, series1, type2);
    dataset.addValue(3.0, series1, type3);
    dataset.addValue(5.0, series1, type4);
    dataset.addValue(5.0, series1, type5);
    dataset.addValue(7.0, series1, type6);
    dataset.addValue(7.0, series1, type7);
    dataset.addValue(8.0, series1, type8);

    dataset.addValue(5.0, series2, type1);
    dataset.addValue(7.0, series2, type2);
    dataset.addValue(6.0, series2, type3);
    dataset.addValue(8.0, series2, type4);
    dataset.addValue(4.0, series2, type5);
    dataset.addValue(4.0, series2, type6);
    dataset.addValue(2.0, series2, type7);
    dataset.addValue(1.0, series2, type8);

    dataset.addValue(4.0, series3, type1);
    dataset.addValue(3.0, series3, type2);
    dataset.addValue(2.0, series3, type3);
    dataset.addValue(3.0, series3, type4);
    dataset.addValue(6.0, series3, type5);
    dataset.addValue(3.0, series3, type6);
    dataset.addValue(4.0, series3, type7);
    dataset.addValue(3.0, series3, type8);

    return dataset;
            
}

/**
 * Creates a sample chart.
 * 
 * @param dataset  a dataset.
 * 
 * @return The chart.
 */
private JFreeChart createChart(final CategoryDataset dataset) {
    
    // create the chart...
    final JFreeChart chart = ChartFactory.createLineChart(
        "Variação de preços",       // chart title
        "Mês",                    // domain axis label
        "Aumento Valor (R$)",                   // range axis label
        dataset,                   // data
        PlotOrientation.VERTICAL,  // orientation
        true,                      // include legend
        true,                      // tooltips
        false                      // urls
    );


    chart.setBackgroundPaint(Color.white);

    final CategoryPlot plot = (CategoryPlot) chart.getPlot();
    plot.setBackgroundPaint(Color.lightGray);
    plot.setRangeGridlinePaint(Color.white);

    // customise the range axis...
    final NumberAxis rangeAxis = (NumberAxis) plot.getRangeAxis();
    rangeAxis.setStandardTickUnits(NumberAxis.createIntegerTickUnits());
    rangeAxis.setAutoRangeIncludesZero(true);

    
    // customise the renderer...
    final LineAndShapeRenderer renderer = (LineAndShapeRenderer) plot.getRenderer();
//        renderer.setDrawShapes(true);
    
    renderer.setSeriesStroke(
        0, new BasicStroke(
            2.0f, BasicStroke.CAP_ROUND, BasicStroke.JOIN_ROUND,
            1.0f, new float[] {10.0f, 6.0f}, 0.0f
        )
    );
    renderer.setSeriesStroke(
        1, new BasicStroke(
            2.0f, BasicStroke.CAP_ROUND, BasicStroke.JOIN_ROUND,
            1.0f, new float[] {6.0f, 6.0f}, 0.0f
        )
    );
    renderer.setSeriesStroke(
        2, new BasicStroke(
            2.0f, BasicStroke.CAP_ROUND, BasicStroke.JOIN_ROUND,
            1.0f, new float[] {2.0f, 6.0f}, 0.0f
        )
    );
    // OPTIONAL CUSTOMISATION COMPLETED.
    
    return chart;
}
}

// Aumento Valor (R$) tem uma linha horizontal para cada um dos valores de 0 até 8
// Tem como colocar uma linha vertical nos meses de Janeiro até Agosto
// Fica fácil ler o aumento pois tem uma linha branca tracejada na horizontal
// Já identificar o aumento no respectivo mês já fica difícil pois não tem a mesma linha na vertical