Apache POI Chart Ось Endarrow

Question

Я пытаюсь получить другое окончание от графика с ведьмой apache Пои.

Это мой код. Это создает эту диаграмму без стрелки. Я не смог найти Axis "Style Class" или что-то в этом роде.

            XSSFDrawing drawing = sheet.createDrawingPatriarch();
            XSSFClientAnchor anchor = drawing.createAnchor(0, 0, 0, 0, 0, 5, 10, 15);

            XSSFChart chart = drawing.createChart(anchor);
            setRoundedCorners(chart, false);
            XDDFChartLegend legend = chart.getOrAddLegend();
            legend.setPosition(LegendPosition.TOP_RIGHT);

            // Use a category axis for the bottom axis.
            XDDFCategoryAxis bottomAxis = chart.createCategoryAxis(AxisPosition.BOTTOM);
            bottomAxis.setTitle("x"); // https://stackoverflow.com/questions/32010765
            //XDDFValueAxis valueAxis = chart.createValueAxis(AxisPosition.BOTTOM);
            //bottomAxis.setMajorTickMark(AxisTickMark.CROSS);
            XDDFValueAxis leftAxis = chart.createValueAxis(AxisPosition.LEFT);
            leftAxis.setTitle("f(x)");
            leftAxis.setCrosses(AxisCrosses.AUTO_ZERO);

Я добавил стрелку после создания. У кого-нибудь сейчас как можно создать стрелку внутри кода?

Я изменил класс Axis на XDDFValueAxis и нашел что-то, похожее на мою функцию размышления, но, к сожалению, бросаю строку 'lineProperties.getHeadEnd ()' an исключение нулевого указателя.

            XDDFValueAxis valueAxis = chart.createValueAxis(AxisPosition.BOTTOM);
            XDDFShapeProperties shapeProperties = valueAxis.getOrAddShapeProperties();
            XDDFLineProperties lineProperties   = shapeProperties.getLineProperties();
            XDDFLineEndProperties lineEndProperties = lineProperties.getHeadEnd();
            lineEndProperties.setType(LineEndType.ARROW);
            valueAxis.setTitle("x");

Как создать XDDFLineEndProperties, защищенный конструктором?

Вот полный пример кода, если необходимо.

mport java.io.FileOutputStream;
import java.io.IOException;

import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.util.CellRangeAddress;
import org.apache.poi.xddf.usermodel.PresetColor;
import org.apache.poi.xddf.usermodel.XDDFColor;
import org.apache.poi.xddf.usermodel.XDDFLineProperties;
import org.apache.poi.xddf.usermodel.XDDFShapeProperties;
import org.apache.poi.xddf.usermodel.XDDFSolidFillProperties;
import org.apache.poi.xddf.usermodel.chart.*;
import org.apache.poi.xssf.usermodel.XSSFChart;
import org.apache.poi.xssf.usermodel.XSSFClientAnchor;
import org.apache.poi.xssf.usermodel.XSSFDrawing;
import org.apache.poi.xssf.usermodel.XSSFSheet;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;

/**
 * Line chart example.
 */
public final class LineChart {
    private LineChart() {}

    public static void main(String[] args) throws IOException {
        try (XSSFWorkbook wb = new XSSFWorkbook()) {


            XSSFSheet sheet = wb.createSheet("linechart");
            final int NUM_OF_ROWS = 3;
            final int NUM_OF_COLUMNS = 10;

            // Create a row and put some cells in it. Rows are 0 based.
            Row row;
            Cell cell;
            for (int rowIndex = 0; rowIndex < NUM_OF_ROWS; rowIndex++) {
                row = sheet.createRow((short) rowIndex);
                for (int colIndex = 0; colIndex < NUM_OF_COLUMNS; colIndex++) {
                    cell = row.createCell((short) colIndex);
                    cell.setCellValue(colIndex * (rowIndex + 1.0) -5 );
                }
            }

            XSSFDrawing drawing = sheet.createDrawingPatriarch();
            XSSFClientAnchor anchor = drawing.createAnchor(0, 0, 0, 0, 0, 5, 10, 15);

            XSSFChart chart = drawing.createChart(anchor);
            setRoundedCorners(chart, false);
            XDDFChartLegend legend = chart.getOrAddLegend();
            legend.setPosition(LegendPosition.TOP_RIGHT);

            // Use a category axis for the bottom axis.
            XDDFCategoryAxis bottomAxis = chart.createCategoryAxis(AxisPosition.BOTTOM);
            bottomAxis.setTitle("x"); // https://stackoverflow.com/questions/32010765
            //XDDFValueAxis valueAxis = chart.createValueAxis(AxisPosition.BOTTOM);
            //bottomAxis.setMajorTickMark(AxisTickMark.CROSS);
            XDDFValueAxis leftAxis = chart.createValueAxis(AxisPosition.LEFT);
            leftAxis.setTitle("f(x)");
            leftAxis.setCrosses(AxisCrosses.AUTO_ZERO);

            XDDFDataSource<Double> xs = XDDFDataSourcesFactory.fromNumericCellRange(sheet, new CellRangeAddress(0, 0, 0, NUM_OF_COLUMNS - 1));
            XDDFNumericalDataSource<Double> ys1 = XDDFDataSourcesFactory.fromNumericCellRange(sheet, new CellRangeAddress(1, 1, 0, NUM_OF_COLUMNS - 1));
            XDDFNumericalDataSource<Double> ys2 = XDDFDataSourcesFactory.fromNumericCellRange(sheet, new CellRangeAddress(2, 2, 0, NUM_OF_COLUMNS - 1));

            XDDFLineChartData data = (XDDFLineChartData) chart.createData(ChartTypes.LINE, bottomAxis, leftAxis);
            XDDFLineChartData.Series series1 = (XDDFLineChartData.Series) data.addSeries(xs, ys1);
            series1.setTitle("2x", null); // https://stackoverflow.com/questions/21855842
            series1.setSmooth(false); // https://stackoverflow.com/questions/29014848
            series1.setMarkerStyle(MarkerStyle.STAR); // https://stackoverflow.com/questions/39636138
            XDDFLineChartData.Series series2 = (XDDFLineChartData.Series) data.addSeries(xs, ys2);
            series2.setTitle("3x", null);
            series2.setSmooth(true);
            series2.setMarkerSize((short) 6);
            series2.setMarkerStyle(MarkerStyle.TRIANGLE); // https://stackoverflow.com/questions/39636138
            chart.plot(data);

            // if your series have missing values like https://stackoverflow.com/questions/29014848
            // chart.displayBlanksAs(DisplayBlanks.GAP);

            // https://stackoverflow.com/questions/24676460
            //solidLineSeries(data, 0, PresetColor.CHARTREUSE);
            //solidLineSeries(data, 1, PresetColor.TURQUOISE);

            // Write the output to a file
            try (FileOutputStream fileOut = new FileOutputStream("ooxml-line-chart.xlsx")) {
                wb.write(fileOut);
            }
        }
    }

    private static void setRoundedCorners(XSSFChart chart, boolean setVal) {
        if (chart.getCTChartSpace().getRoundedCorners() == null) chart.getCTChartSpace().addNewRoundedCorners();
        chart.getCTChartSpace().getRoundedCorners().setVal(setVal);


    }

    private static void solidLineSeries(XDDFChartData data, int index, PresetColor color) {
        XDDFSolidFillProperties fill = new XDDFSolidFillProperties(XDDFColor.from(color));
        XDDFLineProperties line = new XDDFLineProperties();
        line.setFillProperties(fill);
        XDDFChartData.Series series = data.getSeries().get(index);
        XDDFShapeProperties properties = series.getShapeProperties();
        if (properties == null) {
            properties = new XDDFShapeProperties();
        }
        properties.setLineProperties(line);
        series.setShapeProperties(properties);
    }
}

Answer 1

У вас может быть класс publi c, который расширяет XDDFLineEndProperties и предоставляет незащищенный конструктор:

import org.apache.poi.xddf.usermodel.XDDFLineEndProperties;
import org.openxmlformats.schemas.drawingml.x2006.main.CTLineEndProperties;

public class MyXDDFLineEndProperties extends XDDFLineEndProperties {
 public MyXDDFLineEndProperties() {
  super(CTLineEndProperties.Factory.newInstance());
 }
}

Тогда вы можете использовать его следующим образом:

...
    // Use a category axis for the bottom axis.
    XDDFCategoryAxis bottomAxis = chart.createCategoryAxis(AxisPosition.BOTTOM);
    bottomAxis.setTitle("x"); // https://stackoverflow.com/questions/32010765

    XDDFShapeProperties shapeProperties = bottomAxis.getOrAddShapeProperties();
    XDDFLineProperties lineProperties = new XDDFLineProperties();
    MyXDDFLineEndProperties lineEndProperties = new MyXDDFLineEndProperties();
    lineEndProperties.setType(LineEndType.ARROW);
    lineProperties.setTailEnd(lineEndProperties);
    shapeProperties.setLineProperties(lineProperties);
...