Java Excel转PDF(免费)

ops/2024/10/18 8:32:15/

目前市面上 Excel 转 PDF 的组件较多:

  • 收费:aspose、GcExcel、spire
  • 开源:jacob、itextpdf

其中收费的组件封装得比较好,代码简洁,转换的效果也很好,但收费也高得离谱:
874a7fbbd006818eb458b5599059775.png
为了成本考虑,就需要考虑开源的组件了,因为它们都是免费的:

  • jacob:目前没有探索出很好的导出效果。
  • itextpdf:已探索出很好的导出效果,达到了与收费组件一致的效果(推荐)。

以下是 itextpdf 的使用步骤:

  1. 引入依赖

    <!-- POI Excel-->
    <dependency><groupId>org.apache.poi</groupId><artifactId>poi</artifactId><version>4.1.1</version>
    </dependency><!-- iText PDF -->
    <dependency><groupId>com.itextpdf</groupId><artifactId>itextpdf</artifactId><version>5.5.13.2</version>
    </dependency>
    
  2. 定义图片信息

    java">import java.io.Serializable;/*** 图片信息*/
    public class PicturesInfo implements Serializable {private static final long serialVersionUID = 1L;/*** 最小行*/private int minRow;/*** 最大行*/private int maxRow;/*** 最小列*/private int minCol;/*** 最大列*/private int maxCol;/*** 扩展*/private String ext;/*** 图片数据*/private byte[] pictureData;public int getMinRow() {return minRow;}public PicturesInfo setMinRow(int minRow) {this.minRow = minRow;return this;}public int getMaxRow() {return maxRow;}public PicturesInfo setMaxRow(int maxRow) {this.maxRow = maxRow;return this;}public int getMinCol() {return minCol;}public PicturesInfo setMinCol(int minCol) {this.minCol = minCol;return this;}public int getMaxCol() {return maxCol;}public PicturesInfo setMaxCol(int maxCol) {this.maxCol = maxCol;return this;}public String getExt() {return ext;}public PicturesInfo setExt(String ext) {this.ext = ext;return this;}public byte[] getPictureData() {return pictureData;}public PicturesInfo setPictureData(byte[] pictureData) {this.pictureData = pictureData;return this;}
    }
    
  3. 定义工具类

    java">import cn.hutool.core.collection.CollUtil;
    import cn.hutool.core.util.StrUtil;
    import com.itextpdf.text.BaseColor;
    import com.itextpdf.text.Document;
    import com.itextpdf.text.DocumentException;
    import com.itextpdf.text.Image;
    import com.itextpdf.text.PageSize;
    import com.itextpdf.text.Phrase;
    import com.itextpdf.text.pdf.BaseFont;
    import com.itextpdf.text.pdf.PdfPCell;
    import com.itextpdf.text.pdf.PdfPTable;
    import com.itextpdf.text.pdf.PdfWriter;
    import lombok.experimental.UtilityClass;
    import org.apache.log4j.Logger;
    import org.apache.poi.hssf.usermodel.HSSFCell;
    import org.apache.poi.hssf.usermodel.HSSFClientAnchor;
    import org.apache.poi.hssf.usermodel.HSSFPicture;
    import org.apache.poi.hssf.usermodel.HSSFPictureData;
    import org.apache.poi.hssf.usermodel.HSSFShape;
    import org.apache.poi.hssf.usermodel.HSSFShapeContainer;
    import org.apache.poi.hssf.usermodel.HSSFSheet;
    import org.apache.poi.hssf.usermodel.HSSFWorkbook;
    import org.apache.poi.ooxml.POIXMLDocumentPart;
    import org.apache.poi.ss.usermodel.Cell;
    import org.apache.poi.ss.usermodel.CellType;
    import org.apache.poi.ss.usermodel.DataFormatter;
    import org.apache.poi.ss.usermodel.DateUtil;
    import org.apache.poi.ss.usermodel.Font;
    import org.apache.poi.ss.usermodel.Row;
    import org.apache.poi.ss.usermodel.Sheet;
    import org.apache.poi.ss.usermodel.Workbook;
    import org.apache.poi.ss.util.CellRangeAddress;
    import org.apache.poi.xssf.usermodel.XSSFCell;
    import org.apache.poi.xssf.usermodel.XSSFClientAnchor;
    import org.apache.poi.xssf.usermodel.XSSFDrawing;
    import org.apache.poi.xssf.usermodel.XSSFPicture;
    import org.apache.poi.xssf.usermodel.XSSFPictureData;
    import org.apache.poi.xssf.usermodel.XSSFShape;
    import org.apache.poi.xssf.usermodel.XSSFSheet;
    import org.apache.poi.xssf.usermodel.XSSFWorkbook;
    import java.io.IOException;
    import java.io.InputStream;
    import java.io.OutputStream;
    import java.nio.file.Files;
    import java.nio.file.Paths;
    import java.text.SimpleDateFormat;
    import java.util.ArrayList;
    import java.util.Date;
    import java.util.HashSet;
    import java.util.List;
    import java.util.Objects;
    import java.util.Set;/*** Excel转PDF* @author 廖航* @date 2024-08-29 10:52*/
    @UtilityClass
    public class ExcelToPdfUtil {/*** 日志输出*/private static final Logger logger = Logger.getLogger(ExcelToPdfUtil.class);/*** 单元格队列*/Set<String> cellSet = new HashSet<>();/*** Excel转PDF* * @param excelPath Excel文件路径* @param pdfPath PDF文件路径* @param excelSuffix Excel文件后缀*/public static void excelToPdf(String excelPath, String pdfPath, String excelSuffix) {try (InputStream in = Files.newInputStream(Paths.get(excelPath));OutputStream out = Files.newOutputStream(Paths.get(pdfPath))) {ExcelToPdfUtil.excelToPdf(in, out, excelSuffix);} catch (Exception e) {logger.error(e.getMessage());}}/*** Excel转PDF并写入输出流** @param inStream    Excel输入流* @param outStream   PDF输出流* @param excelSuffix Excel类型 .xls 和 .xlsx* @throws Exception 异常信息*/public static void excelToPdf(InputStream inStream, OutputStream outStream, String excelSuffix) throws Exception {// 输入流转workbook,获取sheetSheet sheet = getPoiSheetByFileStream(inStream, 0, excelSuffix);// 获取列宽度占比float[] widths = getColWidth(sheet);PdfPTable table = new PdfPTable(widths);table.setWidthPercentage(100);int colCount = widths.length;//设置基本字体BaseFont baseFont = BaseFont.createFont("C:\\Windows\\Fonts\\simsun.ttc,0", BaseFont.IDENTITY_H, BaseFont.EMBEDDED);// 遍历行for (int rowIndex = sheet.getFirstRowNum(); rowIndex <= sheet.getLastRowNum(); rowIndex++) {Row row = sheet.getRow(rowIndex);if (Objects.isNull(row)) {// 插入空对象for (int i = 0; i < colCount; i++) {table.addCell(createPdfPCell(null, 0, 13f, null));}} else {// 遍历单元格for (int columnIndex = 0; (columnIndex < row.getLastCellNum() || columnIndex < colCount) && columnIndex > -1; columnIndex++) {PdfPCell pCell = excelCellToPdfCell(sheet, row.getCell(columnIndex), baseFont);// 是否合并单元格if (isMergedRegion(sheet, rowIndex, columnIndex)) {int[] span = getMergedSpan(sheet, rowIndex, columnIndex);//忽略合并过的单元格boolean mergedCell = span[0] == 1 && span[1] == 1;if (mergedCell) {continue;}pCell.setRowspan(span[0]);pCell.setColspan(span[1]);}table.addCell(pCell);}}}// 初始化PDF文档对象createPdfTableAndWriteDocument(outStream, table);}/*** 单元格转换,poi cell 转换为 itext cell** @param sheet     poi sheet页* @param excelCell poi 单元格* @param baseFont  基础字体* @return PDF单元格*/private static PdfPCell excelCellToPdfCell(Sheet sheet, Cell excelCell, BaseFont baseFont) throws Exception {if (Objects.isNull(excelCell)) {return createPdfPCell(null, 0, 13f, null);}int rowIndex = excelCell.getRowIndex();int columnIndex = excelCell.getColumnIndex();// 图片信息List<PicturesInfo> infos = getAllPictureInfos(sheet, rowIndex, rowIndex, columnIndex, columnIndex, false);PdfPCell pCell;if (CollUtil.isNotEmpty(infos)) {Image image = Image.getInstance(infos.get(0).getPictureData());// 调整图片大小image.scaleAbsolute(527, 215);pCell = new PdfPCell(image);} else {Font excelFont = getExcelFont(sheet, excelCell);//设置单元格字体com.itextpdf.text.Font pdFont = new com.itextpdf.text.Font(baseFont, excelFont.getFontHeightInPoints(), excelFont.getBold() ? 1 : 0, BaseColor.BLACK);Integer border = hasBorder(excelCell) ? null : 0;String excelCellValue = getExcelCellValue(excelCell);pCell = createPdfPCell(excelCellValue, border, excelCell.getRow().getHeightInPoints(), pdFont);}// 水平居中pCell.setHorizontalAlignment(getHorAlign(excelCell.getCellStyle().getAlignment().getCode()));// 垂直对齐pCell.setVerticalAlignment(getVerAlign(excelCell.getCellStyle().getVerticalAlignment().getCode()));return pCell;}/*** 创建pdf文档,并添加表格** @param outStream 输出流,目标文档* @param table     表格* @throws DocumentException 异常信息*/private static void createPdfTableAndWriteDocument(OutputStream outStream, PdfPTable table) throws DocumentException {//设置pdf纸张大小 PageSize.A4 A4横向Document document = new Document(PageSize.B0);PdfWriter.getInstance(document, outStream);//设置页边距 宽document.setMargins(10, 10, 10, 10);document.open();document.add(table);document.close();}/*** Excel文档输入流转换为对应的workbook及获取对应的sheet** @param inputStream Excel文档输入流* @param sheetNo     sheet编号,默认0 第一个sheet* @param excelSuffix 文件类型 .xls和.xlsx* @return poi sheet* @throws IOException 异常*/public static Sheet getPoiSheetByFileStream(InputStream inputStream, int sheetNo, String excelSuffix) throws IOException {Workbook workbook;if (excelSuffix.endsWith(".xlsx")) {workbook = new XSSFWorkbook(inputStream);} else {workbook = new HSSFWorkbook(inputStream);}return workbook.getSheetAt(sheetNo);}/*** 创建itext pdf 单元格** @param content       单元格内容* @param border        边框* @param minimumHeight 高度* @param pdFont        字体* @return pdf cell*/private static PdfPCell createPdfPCell(String content, Integer border, Float minimumHeight, com.itextpdf.text.Font pdFont) {String contentValue = content == null ? "" : content;com.itextpdf.text.Font pdFontNew = pdFont == null ? new com.itextpdf.text.Font() : pdFont;PdfPCell pCell = new PdfPCell(new Phrase(contentValue, pdFontNew));if (Objects.nonNull(border)) {pCell.setBorder(border);}if (Objects.nonNull(minimumHeight)) {pCell.setMinimumHeight(minimumHeight);}return pCell;}/*** excel垂直对齐方式映射到pdf对齐方式* * @param align 对齐* @return 结果*/private static int getVerAlign(int align) {switch (align) {case 2:return com.itextpdf.text.Element.ALIGN_BOTTOM;case 3:return com.itextpdf.text.Element.ALIGN_TOP;default:return com.itextpdf.text.Element.ALIGN_MIDDLE;}}/*** excel水平对齐方式映射到pdf水平对齐方式* * @param align 对齐* @return 结果*/private static int getHorAlign(int align) {switch (align) {case 1:return com.itextpdf.text.Element.ALIGN_LEFT;case 3:return com.itextpdf.text.Element.ALIGN_RIGHT;default:return com.itextpdf.text.Element.ALIGN_CENTER;}}/*============================================== POI获取图片及文本内容工具方法 ==============================================*//*** 获取字体** @param sheet excel 转换的sheet页* @param cell  单元格* @return 字体*/private static Font getExcelFont(Sheet sheet, Cell cell) {// xlsif (sheet instanceof HSSFSheet) {Workbook workbook = sheet.getWorkbook();return ((HSSFCell) cell).getCellStyle().getFont(workbook);}// xlsxreturn ((XSSFCell) cell).getCellStyle().getFont();}/*** 判断excel单元格是否有边框* * @param excelCell 单元格* @return 结果*/private static boolean hasBorder(Cell excelCell) {short top = excelCell.getCellStyle().getBorderTop().getCode();short bottom = excelCell.getCellStyle().getBorderBottom().getCode();short left = excelCell.getCellStyle().getBorderLeft().getCode();short right = excelCell.getCellStyle().getBorderRight().getCode();return top + bottom + left + right > 2;}/*** 判断单元格是否是合并单元格* * @param sheet 表* @param row 行* @param column 列* @return 结果*/private static boolean isMergedRegion(Sheet sheet, int row, int column) {int sheetMergeCount = sheet.getNumMergedRegions();for (int i = 0; i < sheetMergeCount; i++) {CellRangeAddress range = sheet.getMergedRegion(i);int firstColumn = range.getFirstColumn();int lastColumn = range.getLastColumn();int firstRow = range.getFirstRow();int lastRow = range.getLastRow();if (row >= firstRow && row <= lastRow) {if (column >= firstColumn && column <= lastColumn) {return true;}}}return false;}/*** 计算合并单元格合并的跨行跨列数* * @param sheet 表* @param row 行* @param column 列* @return 结果*/private static int[] getMergedSpan(Sheet sheet, int row, int column) {int sheetMergeCount = sheet.getNumMergedRegions();int[] span = {1, 1};for (int i = 0; i < sheetMergeCount; i++) {CellRangeAddress range = sheet.getMergedRegion(i);int firstColumn = range.getFirstColumn();int lastColumn = range.getLastColumn();int firstRow = range.getFirstRow();int lastRow = range.getLastRow();if (firstColumn == column && firstRow == row) {span[0] = lastRow - firstRow + 1;span[1] = lastColumn - firstColumn + 1;break;}}return span;}/*** 获取excel中每列宽度的占比* * @param sheet 表* @return 结果*/private static float[] getColWidth(Sheet sheet) {int rowNum = getMaxColRowNum(sheet);Row row = sheet.getRow(rowNum);int cellCount = row.getPhysicalNumberOfCells();int[] colWidths = new int[cellCount];int sum = 0;for (int i = row.getFirstCellNum(); i < cellCount; i++) {Cell cell = row.getCell(i);if (cell != null) {colWidths[i] = sheet.getColumnWidth(i);sum += sheet.getColumnWidth(i);}}float[] colWidthPer = new float[cellCount];for (int i = row.getFirstCellNum(); i < cellCount; i++) {colWidthPer[i] = (float) colWidths[i] / sum * 100;}return colWidthPer;}/*** 获取excel中列数最多的行号* * @param sheet 表* @return 结果*/private static int getMaxColRowNum(Sheet sheet) {int rowNum = 0;int maxCol = 0;for (int r = sheet.getFirstRowNum(); r < sheet.getPhysicalNumberOfRows(); r++) {Row row = sheet.getRow(r);if (row != null && maxCol < row.getPhysicalNumberOfCells()) {maxCol = row.getPhysicalNumberOfCells();rowNum = r;}}return rowNum;}/*** poi 根据单元格类型获取单元格内容** @param excelCell poi单元格* @return 单元格内容文本*/public static String getExcelCellValue(Cell excelCell) {if (excelCell == null) {return "";}// 判断数据的类型CellType cellType = excelCell.getCellType();if (cellType == CellType.STRING) {return excelCell.getStringCellValue();}if (cellType == CellType.BOOLEAN) {return String.valueOf(excelCell.getBooleanCellValue());}if (cellType == CellType.FORMULA) {return excelCell.getCellFormula();}if (cellType == CellType.NUMERIC) {// 处理日期格式、时间格式if (DateUtil.isCellDateFormatted(excelCell)) {SimpleDateFormat sdf;// 验证short值if (excelCell.getCellStyle().getDataFormat() == 14) {sdf = new SimpleDateFormat("yyyy/MM/dd");} else if (excelCell.getCellStyle().getDataFormat() == 21) {sdf = new SimpleDateFormat("HH:mm:ss");} else if (excelCell.getCellStyle().getDataFormat() == 22) {sdf = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss");} else {throw new RuntimeException("日期格式错误!!!");}Date date = excelCell.getDateCellValue();return sdf.format(date);} else if (excelCell.getCellStyle().getDataFormat() == 0) {//处理数值格式DataFormatter formatter = new DataFormatter();return formatter.formatCellValue(excelCell);}}if (cellType == CellType.ERROR) {return "非法字符";}return "";}/*** 获取sheet内的所有图片信息** @param sheet        sheet表* @param onlyInternal 单元格内部* @return 照片集合* @throws Exception 异常*/public static List<PicturesInfo> getAllPictureInfos(Sheet sheet, boolean onlyInternal) throws Exception {return getAllPictureInfos(sheet, null, null, null, null, onlyInternal);}/*** 根据sheet和单元格信息获取图片** @param sheet        sheet表* @param minRow       最小行* @param maxRow       最大行* @param minCol       最小列* @param maxCol       最大列* @param onlyInternal 是否内部* @return 图片集合* @throws Exception 异常*/public static List<PicturesInfo> getAllPictureInfos(Sheet sheet, Integer minRow, Integer maxRow, Integer minCol,Integer maxCol, boolean onlyInternal) throws Exception {if (sheet instanceof HSSFSheet) {return getXLSAllPictureInfos((HSSFSheet) sheet, minRow, maxRow, minCol, maxCol, onlyInternal);} else if (sheet instanceof XSSFSheet) {return getXLSXAllPictureInfos((XSSFSheet) sheet, minRow, maxRow, minCol, maxCol, onlyInternal);} else {throw new Exception("未处理类型,没有为该类型添加:GetAllPicturesInfos()扩展方法!");}}/*** 获取XLS图片信息* * @param sheet 表* @param minRow 最小行* @param maxRow 最大行* @param minCol 最小列* @param maxCol 最大列* @param onlyInternal 只在内部* @return 图片信息列表*/private static List<PicturesInfo> getXLSAllPictureInfos(HSSFSheet sheet, Integer minRow, Integer maxRow,Integer minCol, Integer maxCol, Boolean onlyInternal) {List<PicturesInfo> picturesInfoList = new ArrayList<>();HSSFShapeContainer shapeContainer = sheet.getDrawingPatriarch();if (shapeContainer == null) {return picturesInfoList;}List<HSSFShape> shapeList = shapeContainer.getChildren();for (HSSFShape shape : shapeList) {if (shape instanceof HSSFPicture && shape.getAnchor() instanceof HSSFClientAnchor) {HSSFPicture picture = (HSSFPicture) shape;HSSFClientAnchor anchor = (HSSFClientAnchor) shape.getAnchor();if (isInternalOrIntersect(minRow, maxRow, minCol, maxCol, anchor.getRow1(), anchor.getRow2(),anchor.getCol1(), anchor.getCol2(), onlyInternal)) {String item = StrUtil.format("{},{},{},{}", anchor.getRow1(), anchor.getRow2(), anchor.getCol1(), anchor.getCol2());if (cellSet.contains(item)) {continue;}cellSet.add(item);HSSFPictureData pictureData = picture.getPictureData();picturesInfoList.add(new PicturesInfo().setMinRow(anchor.getRow1()).setMaxRow(anchor.getRow2()).setMinCol(anchor.getCol1()).setMaxCol(anchor.getCol2()).setPictureData(pictureData.getData()).setExt(pictureData.getMimeType()));}}}return picturesInfoList;}/*** 获取XLSX图片信息* * @param sheet 表* @param minRow 最小行* @param maxRow 最大行* @param minCol 最小列* @param maxCol 最大列* @param onlyInternal 只在内部* @return 图片信息列表*/private static List<PicturesInfo> getXLSXAllPictureInfos(XSSFSheet sheet, Integer minRow, Integer maxRow,Integer minCol, Integer maxCol, Boolean onlyInternal) {List<PicturesInfo> picturesInfoList = new ArrayList<>();List<POIXMLDocumentPart> documentPartList = sheet.getRelations();for (POIXMLDocumentPart documentPart : documentPartList) {if (documentPart instanceof XSSFDrawing) {XSSFDrawing drawing = (XSSFDrawing) documentPart;List<XSSFShape> shapes = drawing.getShapes();for (XSSFShape shape : shapes) {if (shape instanceof XSSFPicture) {XSSFPicture picture = (XSSFPicture) shape;XSSFClientAnchor anchor = picture.getPreferredSize();if (isInternalOrIntersect(minRow, maxRow, minCol, maxCol, anchor.getRow1(), anchor.getRow2(),anchor.getCol1(), anchor.getCol2(), onlyInternal)) {String item = StrUtil.format("{},{},{},{}", anchor.getRow1(), anchor.getRow2(), anchor.getCol1(), anchor.getCol2());if (cellSet.contains(item)) {continue;}cellSet.add(item);XSSFPictureData pictureData = picture.getPictureData();picturesInfoList.add(new PicturesInfo().setMinRow(anchor.getRow1()).setMaxRow(anchor.getRow2()).setMinCol(anchor.getCol1()).setMaxCol(anchor.getCol2()).setPictureData(pictureData.getData()).setExt(pictureData.getMimeType()));}}}}}return picturesInfoList;}/*** 是内部的或相交的* * @param rangeMinRow 最小行范围* @param rangeMaxRow 最大行范围* @param rangeMinCol 最小列范围* @param rangeMaxCol 最大列范围* @param pictureMinRow 图片最小行* @param pictureMaxRow 图片最大行* @param pictureMinCol 图片最小列* @param pictureMaxCol 图片最大列* @param onlyInternal 只在内部* @return 结果*/private static boolean isInternalOrIntersect(Integer rangeMinRow, Integer rangeMaxRow, Integer rangeMinCol,Integer rangeMaxCol, int pictureMinRow, int pictureMaxRow, int pictureMinCol, int pictureMaxCol,Boolean onlyInternal) {int _rangeMinRow = rangeMinRow == null ? pictureMinRow : rangeMinRow;int _rangeMaxRow = rangeMaxRow == null ? pictureMaxRow : rangeMaxRow;int _rangeMinCol = rangeMinCol == null ? pictureMinCol : rangeMinCol;int _rangeMaxCol = rangeMaxCol == null ? pictureMaxCol : rangeMaxCol;if (onlyInternal) {return (_rangeMinRow <= pictureMinRow && _rangeMaxRow >= pictureMaxRow && _rangeMinCol <= pictureMinCol&& _rangeMaxCol >= pictureMaxCol);} else {return ((Math.abs(_rangeMaxRow - _rangeMinRow) + Math.abs(pictureMaxRow - pictureMinRow) >= Math.abs(_rangeMaxRow + _rangeMinRow - pictureMaxRow - pictureMinRow))&& (Math.abs(_rangeMaxCol - _rangeMinCol) + Math.abs(pictureMaxCol - pictureMinCol) >= Math.abs(_rangeMaxCol + _rangeMinCol - pictureMaxCol - pictureMinCol)));}}
    }
    
  4. 调用工具类

    java">ExcelToPdfUtil.excelToPdf("原始的Excel文件", "要导出的PDF文件", ".xlsx");
    

如此,即可很好的实现 Excel 转 PDF。


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