Actualmente estoy usandoitext-pdf para generar archivos PDF. Además de eso, también estoy usandoJFreeChart para crear gráficos en él. He creado un gráfico de donas con un efecto de explosión y se ve así.

Sin embargo, quiero crear un gráfico de donas que se parezca más a esto.

Quiero que ciertas piezas se destaquen, pero que no se separen por completo de la tabla de donas. Agradecería mucho las aportaciones sobre cómo lograr esto.

Aquí está mi código actual:

import java.awt.Color;
import java.awt.Graphics2D;
import java.awt.geom.Rectangle2D;
import java.io.FileOutputStream;
import java.io.IOException;
import java.text.DecimalFormat;
import java.util.Locale;

import org.jfree.chart.ChartFactory;
import org.jfree.chart.JFreeChart;
import org.jfree.chart.labels.StandardPieSectionLabelGenerator;
import org.jfree.chart.plot.PiePlotState;
import org.jfree.chart.plot.RingPlot;
import org.jfree.data.general.DefaultPieDataset;
import org.jfree.ui.RectangleInsets;


import com.itextpdf.awt.DefaultFontMapper;
import com.itextpdf.text.BaseColor;
import com.itextpdf.text.Document;
import com.itextpdf.text.DocumentException;
import com.itextpdf.text.Element;
import com.itextpdf.text.Font;
import com.itextpdf.text.PageSize;
import com.itextpdf.text.Phrase;
import com.itextpdf.text.pdf.BaseFont;
import com.itextpdf.text.pdf.ColumnText;
import com.itextpdf.text.pdf.PdfContentByte;
import com.itextpdf.text.pdf.PdfTemplate;
import com.itextpdf.text.pdf.PdfWriter;

public class RingChartTest {
    public static void main(String[] args) throws Exception {
        new RingChartTest().createPDF();
    }

    private void createPDF() throws Exception {
        String destination = "ringchart.pdf";

        Document document = new Document(PageSize.A4.rotate());
        try {
            PdfWriter writer = PdfWriter.getInstance(document, new FileOutputStream(destination));
            document.open();

            // Create the pages
            PdfContentByte cb = writer.getDirectContent();
            addChart(cb);
        } catch (Exception e) {
            System.out.println("Failure to generate the PDF");
            e.printStackTrace();
        } finally {
            if (document != null) {
                document.close();        
            }
        }
    }

    private void addChart(PdfContentByte cb) throws Exception, IOException {
        long pctPM = Math.round(20);
        long pctOA = Math.round(15);
        long pctWPI = Math.round(5);
        long pctTDF = Math.round(25);
        long pctNE = 100 - (pctPM + pctOA + pctWPI + pctTDF);
        long pctEngaged = pctPM + pctOA + pctWPI;
        long numEngaged = 3400;
        String strNumEngaged = formatNumber(numEngaged, "#,###,###,##0");


        JFreeChart chart = createChart(pctPM, pctOA, pctWPI, pctTDF, pctNE);

        int width = 300;
        int height = 200;
        PdfTemplate template = cb.createTemplate(width, height);
        Graphics2D graphics2d = template.createGraphics(width, height, new DefaultFontMapper());
        Rectangle2D rectangle2d = new Rectangle2D.Double(0, 0, width, height);
        chart.draw(graphics2d, rectangle2d);
        graphics2d.dispose();
        cb.addTemplate(template, 30, 185);  

        // Add text inside chart
        Font engagementFont = createFont("OpenSans-Bold.ttf", 8, 116, 112, 100);
        Font percentFont1 = createFont("OpenSans-Light.ttf", 22, 116, 112, 100);
        Font percentFont2 = createFont("OpenSans-Light.ttf", 10, 116, 112, 100);
        Font numberFont = createFont("OpenSans-Regular.ttf", 8, 116, 112, 100);
        addPhrase(cb, "ENGAGE", engagementFont, 135, 290, 230, 310, 10, Element.ALIGN_CENTER);
        addPhrase(cb, String.valueOf(pctEngaged), percentFont1, 115, 270, 190, 289, 10, Element.ALIGN_RIGHT);
        addPhrase(cb, "%", percentFont2, 191, 275, 201, 299, 10, Element.ALIGN_LEFT);
        addPhrase(cb, "(" + strNumEngaged + ")", numberFont, 130, 258, 230, 278, 10, Element.ALIGN_CENTER);

        // Create legend
        // 290,420,370,520,10,Element.ALIGN_CENTER);
        BaseFont engagedPctFont = createBaseFont("OpenSans-Bold.ttf");
        BaseFont engagedDescFont = createBaseFont("OpenSans-SemiBold.ttf");
        BaseFont nonEngagedDescFont = createBaseFont("OpenSans-Regular.ttf");
        BaseColor pmBaseColor = new BaseColor(31, 160, 200);
        BaseColor oaBaseColor = new BaseColor(84, 193, 209);
        BaseColor wpiBaseColor = new BaseColor(248, 156, 36);
        BaseColor tdfBaseColor = new BaseColor(116, 112, 94);
        BaseColor nonEngagedBaseColor = new BaseColor(148, 144, 132);
        float x = 330;
        float y = 350;
        float radius = 3;

        // Create border around legend
        /*
        cb.setColorFill(new BaseColor(255, 255, 255));
        cb.rectangle(320, 300, 150, 70);
        cb.re
        cb.fill();
        */
        BaseColor borderColor = new BaseColor(192, 189, 178);
        cb.setColorStroke(borderColor);
        cb.moveTo(320, 300);
        cb.lineTo(320, 365);
        cb.lineTo(500, 365);
        cb.lineTo(500, 300);
        cb.lineTo(320, 300);
        cb.closePathStroke();

        // Prof Mgmt
        cb.setColorFill(pmBaseColor);
        cb.circle(x, y, radius);
        cb.fill();
        addTextToCanvas(cb, pctPM+"%", engagedPctFont, 8, new BaseColor(116, 112, 100), x+20, y-2);
        addTextToCanvas(cb, "Pg", engagedDescFont, 8, new BaseColor(116, 112, 100), x+50, y-2);
        // Online Advice
        cb.setColorFill(oaBaseColor);
        cb.circle(x, y-20, radius);
        cb.fill();
        addTextToCanvas(cb, pctOA+"%", engagedPctFont, 8, new BaseColor(116, 112, 100), x+20, y-22);
        addTextToCanvas(cb, "Oaa", engagedDescFont, 8, new BaseColor(116, 112, 100), x+50, y-22);
        // Clicked WPI/Online Guidance
        cb.setColorFill(wpiBaseColor);
        cb.circle(x, y-40, radius);
        cb.fill();
        addTextToCanvas(cb, pctWPI+"%", engagedPctFont, 8, new BaseColor(116, 112, 100), x+20, y-42);
        addTextToCanvas(cb, "Ogg", engagedDescFont, 8, new BaseColor(116, 112, 100), x+50, y-42);
        if (pctTDF > 0) {
            // TDF Users
            cb.setColorFill(tdfBaseColor);
            cb.circle(x, y-60, radius);
            cb.fill();
            addTextToCanvas(cb, pctTDF+"%", engagedPctFont, 8, new BaseColor(116, 112, 100), x+20, y-62);
            addTextToCanvas(cb, "Pti*", nonEngagedDescFont, 8, new BaseColor(116, 112, 100), x+50, y-62);
            // Non-engaged
            cb.setColorFill(nonEngagedBaseColor);
            cb.circle(x, y-80, radius);
            cb.fill();
            addTextToCanvas(cb, pctNE+"%", engagedPctFont, 8, new BaseColor(116, 112, 100), x+20, y-82);
            addTextToCanvas(cb, "Nng", nonEngagedDescFont, 8, new BaseColor(116, 112, 100), x+50, y-82);
        } else {
            // Non-engaged
            cb.setColorFill(nonEngagedBaseColor);
            cb.circle(x, y-60, radius);
            cb.fill();
            addTextToCanvas(cb, pctNE+"%", engagedPctFont, 8, new BaseColor(116, 112, 100), x+20, y-62);
            addTextToCanvas(cb, "ngd", nonEngagedDescFont, 8, new BaseColor(116, 112, 100), x+50, y-62);,
        }
    }

    private String formatNumber(double value, String strFormat) {
        DecimalFormat df = new DecimalFormat( strFormat );
        return df.format(value);
    }

    private void addPhrase(PdfContentByte cb, String strText, Font font, float llx, float lly, float urx, float ury, float leading, int alignment) throws DocumentException {
        Phrase phrase = new Phrase(strText, font);
        ColumnText ct = new ColumnText(cb);
        ct.setSimpleColumn(phrase, llx, lly, urx, ury, leading, alignment);
        ct.go();
    }

    private void addTextToCanvas(PdfContentByte cb, String strText, BaseFont font, float fontSize, BaseColor color, float x, float y) {
        cb.beginText();
        cb.setFontAndSize(font, fontSize);
        cb.setColorFill(color);
        cb.showTextAligned(Element.ALIGN_LEFT, strText, x, y, 0);
        cb.endText();
    }

    private BaseFont createBaseFont(String fileName) throws DocumentException, IOException {
        return BaseFont.createFont(PdfGenerationController.LOCATION_FONTS + fileName ,BaseFont.IDENTITY_H, BaseFont.EMBEDDED);
    }

    private Font createFont(String fileName, float size, int red, int green, int blue) throws DocumentException, IOException {
        BaseFont baseFont = BaseFont.createFont(PdfGenerationController.LOCATION_FONTS + fileName ,BaseFont.IDENTITY_H, BaseFont.EMBEDDED);
        Font font = new Font(baseFont, size);
        font.setColor(red, green, blue);
        return font;
    }

    public JFreeChart createChart(long pctPM, long pctOA, long pctWPI, long pctTDF, long pctNE) {
        // Set up the data set for the donut/ring chart
        DefaultPieDataset rDataSet =  new DefaultPieDataset();
        rDataSet.setValue("PM", pctPM );
        rDataSet.setValue("OA", pctOA);  
        rDataSet.setValue("WPI", pctWPI);
        rDataSet.setValue("TDF", pctTDF);
        rDataSet.setValue("NE", pctNE);

        // Initialize values
        boolean bShowLegend = false;
        String strTitle = null;

        // Create ring plot
        CustomDonutPlot rPlot = new CustomDonutPlot(rDataSet);
        //RingPlot rPlot = new RingPlot(rDataSet);
        rPlot.setLabelGenerator(new StandardPieSectionLabelGenerator(Locale.ENGLISH));
        rPlot.setInsets(new RectangleInsets(0.0, 5.0, 5.0, 5.0));
        rPlot.setSectionDepth(0.30);
        JFreeChart chart = new JFreeChart(strTitle, JFreeChart.DEFAULT_TITLE_FONT, rPlot, bShowLegend);
        ChartFactory.getChartTheme().apply(chart);        

        // Create the chart
        //JFreeChart rChart = ChartFactory.createRingChart(null, rDataSet , false, false, Locale.ENGLISH);
        //RingPlot rPlot = (RingPlot) rChart.getPlot();
        rPlot.setBackgroundPaint(Color.WHITE);
        rPlot.setCenterText(null);
        rPlot.setLabelGenerator(null); 
        rPlot.setOutlineVisible(false);
        rPlot.setShadowGenerator(null);
        rPlot.setSeparatorsVisible(false);
        rPlot.setShadowPaint(null);
        rPlot.setSectionOutlinesVisible(false);
        rPlot.setOuterSeparatorExtension(0);
        rPlot.setInnerSeparatorExtension(0);

        // Set colors of the chart
        rPlot.setSectionPaint("PM", new Color(31, 160, 200));
        rPlot.setSectionPaint("OA", new Color(84, 193, 209));
        rPlot.setSectionPaint("WPI", new Color(248, 156, 36));
        rPlot.setSectionPaint("TDF", new Color(116, 112, 94));
        rPlot.setSectionPaint("NE", new Color(148, 144, 132));

        rPlot.setExplodePercent("PM", 0.05);
        rPlot.setExplodePercent("OA", 0.05);
        rPlot.setExplodePercent("WPI", 0.05);

        return chart;
    }

    public static class CustomDonutPlot extends RingPlot {
        private static final long serialVersionUID = 1L;

        public CustomDonutPlot(DefaultPieDataset dataSet) {
            super(dataSet);
        }

        @Override
        protected void drawItem(Graphics2D g2, int section, Rectangle2D dataArea, PiePlotState state, int currentPass) {
            if (currentPass == 1 && section >=1 && section <= 3) {

            }
            Rectangle2D area = state.getPieArea();
            System.out.println("*** At section=" + section + ", pass="+currentPass);
            logDataArea(dataArea, "Data area");
            logDataArea(area, "Pie area");
            System.out.println(state.getInfo());

            super.drawItem(g2, section, dataArea, state, currentPass);


        }

        private void logDataArea(Rectangle2D dataArea, String msg) {
            System.out.println(msg + " h="+dataArea.getHeight() + ", w=" + dataArea.getWidth() + ", x=" + dataArea.getX() + ",y="+dataArea.getY());
        }


    }
}

Esta versión alternativa aísla el gráfico del PDF.

import java.awt.Color;
import java.awt.EventQueue;
import java.awt.Graphics2D;
import java.awt.geom.Rectangle2D;
import java.util.Locale;
import javax.swing.JFrame;
import org.jfree.chart.ChartFactory;
import org.jfree.chart.ChartPanel;
import org.jfree.chart.JFreeChart;
import org.jfree.chart.labels.StandardPieSectionLabelGenerator;
import org.jfree.chart.plot.PiePlotState;
import org.jfree.chart.plot.RingPlot;
import org.jfree.data.general.DefaultPieDataset;
import org.jfree.ui.RectangleInsets;

/**
 * @see http://stackoverflow.com/q/37213030/230513
 */
public class Test {

    private void display() {
        JFrame f = new JFrame("Test");
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        long pctPM = Math.round(20);
        long pctOA = Math.round(15);
        long pctWPI = Math.round(5);
        long pctTDF = Math.round(25);
        long pctNE = 100 - (pctPM + pctOA + pctWPI + pctTDF);
        f.add(new ChartPanel(createChart(pctPM, pctOA, pctWPI, pctTDF, pctNE)));
        f.pack();
        f.setLocationRelativeTo(null);
        f.setVisible(true);
    }

    public JFreeChart createChart(long pctPM, long pctOA, long pctWPI, long pctTDF, long pctNE) {
        // Set up the data set for the donut/ring chart
        DefaultPieDataset rDataSet = new DefaultPieDataset();
        rDataSet.setValue("PM", pctPM);
        rDataSet.setValue("OA", pctOA);
        rDataSet.setValue("WPI", pctWPI);
        rDataSet.setValue("TDF", pctTDF);
        rDataSet.setValue("NE", pctNE);

        // Initialize values
        boolean bShowLegend = false;
        String strTitle = null;

        // Create ring plot
        CustomDonutPlot rPlot = new CustomDonutPlot(rDataSet);
        //RingPlot rPlot = new RingPlot(rDataSet);
        rPlot.setLabelGenerator(new StandardPieSectionLabelGenerator(Locale.ENGLISH));
        rPlot.setInsets(new RectangleInsets(0.0, 5.0, 5.0, 5.0));
        rPlot.setSectionDepth(0.30);
        JFreeChart chart = new JFreeChart(strTitle, JFreeChart.DEFAULT_TITLE_FONT, rPlot, bShowLegend);
        ChartFactory.getChartTheme().apply(chart);

        // Create the chart
        //JFreeChart rChart = ChartFactory.createRingChart(null, rDataSet , false, false, Locale.ENGLISH);
        //RingPlot rPlot = (RingPlot) rChart.getPlot();
        rPlot.setBackgroundPaint(Color.WHITE);
        rPlot.setCenterText(null);
        rPlot.setLabelGenerator(null);
        rPlot.setOutlineVisible(false);
        rPlot.setShadowGenerator(null);
        rPlot.setSeparatorsVisible(false);
        rPlot.setShadowPaint(null);
        rPlot.setSectionOutlinesVisible(false);
        rPlot.setOuterSeparatorExtension(0);
        rPlot.setInnerSeparatorExtension(0);

        // Set colors of the chart
        rPlot.setSectionPaint("PM", new Color(31, 160, 200));
        rPlot.setSectionPaint("OA", new Color(84, 193, 209));
        rPlot.setSectionPaint("WPI", new Color(248, 156, 36));
        rPlot.setSectionPaint("TDF", new Color(116, 112, 94));
        rPlot.setSectionPaint("NE", new Color(148, 144, 132));

        rPlot.setExplodePercent("PM", 0.05);
        rPlot.setExplodePercent("OA", 0.05);
        rPlot.setExplodePercent("WPI", 0.05);

        return chart;
    }

    public static class CustomDonutPlot extends RingPlot {

        private static final long serialVersionUID = 1L;

        public CustomDonutPlot(DefaultPieDataset dataSet) {
            super(dataSet);
        }

        @Override
        protected void drawItem(Graphics2D g2, int section, Rectangle2D dataArea, PiePlotState state, int currentPass) {
            super.drawItem(g2, section, dataArea, state, currentPass);
            Rectangle2D area = state.getPieArea();
            System.out.println("*** At section=" + section + ", pass=" + currentPass);
            logDataArea(dataArea, "Data area");
            logDataArea(area, "Pie area");
        }

        private void logDataArea(Rectangle2D dataArea, String msg) {
            System.out.println(msg + " h=" + dataArea.getHeight() + ", w=" + dataArea.getWidth() + ", x=" + dataArea.getX() + ",y=" + dataArea.getY());
        }
    }

    public static void main(String[] args) {
        EventQueue.invokeLater(new Test()::display);
    }
}