使用Apache POI创建Excel折线图教程

本教程将指导您使用Apache POI库在Excel工作簿中创建折线图。我们将逐步介绍整个过程，包括读取Excel文件、创建图表对象、添加数据系列、设置坐标轴格式以及自定义图表外观。

1. 项目设置

确保您的项目中包含以下POI库依赖项： * poi * poi-ooxml * poi-ooxml-schemas

2. 代码示例javaimport org.apache.poi.ss.usermodel.Cell;import org.apache.poi.ss.util.CellRangeAddress;import org.apache.poi.xddf.usermodel.chart.;import org.apache.poi.xssf.usermodel.;

import java.io.FileInputStream;import java.io.FileOutputStream;import java.io.IOException;import java.text.SimpleDateFormat;import java.util.Date;

public class ExcelChartExample02 {

public static void main(String[] args) {        try {            // 读取Excel文件            FileInputStream fileIn = new FileInputStream('巴新EDEVU水库数据处理表.xlsx');            XSSFWorkbook workbook = new XSSFWorkbook(fileIn);            XSSFSheet sheet1 = workbook.getSheet('P9');            XSSFSheet sheet2 = workbook.getSheet('P10');

        // 创建折线图            XSSFDrawing drawing = sheet2.createDrawingPatriarch();            XSSFClientAnchor anchor = drawing.createAnchor(0, 0, 0, 0, 3, 9, 9, 19);            XSSFChart chart = drawing.createChart(anchor);            chart.setTitleText('数据折线图');            chart.setTitleOverlay(false);

        // 设置图例位置            XDDFChartLegend legend = chart.getOrAddLegend();            legend.setPosition(LegendPosition.BOTTOM);

        // 设置横坐标轴            XDDFCategoryAxis bottomAxis = chart.createCategoryAxis(AxisPosition.BOTTOM);            bottomAxis.setTitle('时间');

        // 设置纵坐标轴            XDDFValueAxis leftAxis = chart.createValueAxis(AxisPosition.LEFT);            leftAxis.setTitle('数据值');

        // 设置数据源            XDDFNumericalDataSource<Double> xs1 = XDDFDataSourcesFactory.fromNumericCellRange(sheet1, new CellRangeAddress(11, 85, 0, 0));            XDDFNumericalDataSource<Double> ys1 = XDDFDataSourcesFactory.fromNumericCellRange(sheet1, new CellRangeAddress(11, 85, 2, 2));            XDDFNumericalDataSource<Double> xs2 = XDDFDataSourcesFactory.fromNumericCellRange(sheet2, new CellRangeAddress(11, 139, 0, 0));            XDDFNumericalDataSource<Double> ys2 = XDDFDataSourcesFactory.fromNumericCellRange(sheet2, new CellRangeAddress(11, 139, 2, 2));

        // 添加数据系列            XDDFLineChartData data = (XDDFLineChartData) chart.createData(ChartTypes.LINE, bottomAxis, leftAxis);            XDDFLineChartData.Series series1 = (XDDFLineChartData.Series) data.addSeries(xs1, ys1);            series1.setTitle('P9数据折线图', null);            XDDFLineChartData.Series series2 = (XDDFLineChartData.Series) data.addSeries(xs2, ys2);            series2.setTitle('P10数据折线图', null);

        // 设置横坐标轴为日期坐标轴            XDDFDataSource<?> dateSource = XDDFDataSourcesFactory.fromNumericCellRange(sheet1, new CellRangeAddress(11, 85, 1, 1));            XDDFDateAxis bottomDateAxis = chart.createDateAxis(AxisPosition.BOTTOM);            bottomDateAxis.setMajorTickMark(AxisTickMark.CROSS);            bottomDateAxis.setMinorTickMark(AxisTickMark.NONE);            bottomDateAxis.setCrosses(AxisCrosses.AUTO_ZERO);            bottomDateAxis.setTitle('时间');            bottomDateAxis.setTickLabelPosition(AxisTickLabelPosition.NEXT_TO);

        // 设置时间格式            SimpleDateFormat dateFormat = new SimpleDateFormat('yyyy-MM-dd');            for (int i = 0; i < dateSource.getPointCount(); i++) {                Cell cell = sheet1.getRow(i + 11).getCell(1);                Date date = cell.getDateCellValue();                if (date != null) {                    String formattedDate = dateFormat.format(date);                    bottomDateAxis.setTickLabelPosition(AxisTickLabelPosition.NEXT_TO);                }            }

        // 绘制图表            chart.plot(data);

        // 创建'温度'工作表            XSSFSheet sheet3 = workbook.createSheet('温度');

        // 将图表复制到'温度'工作表            XSSFDrawing drawing2 = sheet3.createDrawingPatriarch();            XSSFClientAnchor anchor2 = drawing2.createAnchor(0, 0, 0, 0, 0, 0, 10, 20);            XSSFChart chart2 = drawing2.createChart(anchor2);            chart2.setTitleText('数据折线图');            chart2.setTitleOverlay(false);            XDDFCategoryAxis bottomAxis2 = chart2.createCategoryAxis(AxisPosition.BOTTOM);            XDDFValueAxis leftAxis2 = chart2.createValueAxis(AxisPosition.LEFT);            leftAxis2.setCrosses(AxisCrosses.AUTO_ZERO);            XDDFLineChartData data2 = (XDDFLineChartData) chart2.createData(ChartTypes.LINE, bottomAxis2, leftAxis2);            data2.addSeries(xs1, ys1);            data2.addSeries(xs2, ys2);            chart2.plot(data2);

        // 保存Excel文件            FileOutputStream fileOut = new FileOutputStream('巴新EDEVU水库数据处理表.xlsx');            workbook.write(fileOut);            fileOut.close();

        System.out.println('折线图已创建并保存到Excel文件中。');

    } catch (IOException e) {            e.printStackTrace();        }