Java Apache POI Excel 另存为 PDF

Posted 2023-02-24

【中文标题】Java Apache POI Excel 另存为 PDF

【英文标题】：Java Apache POI Excel save as PDF

【发布时间】：2014-11-21 06:48:01

【问题描述】：

如何将excel 文件转换/保存为pdf？我正在使用java play framework 生成一些excel 文件，现在需求更改为pdf。我不想重新编码所有内容。

有没有办法转换成pdf？

我生成的excel 文件来自模板；我阅读了 excel 模板文件，编写了更改，然后另存为新的 excel 文件。这样，模板就不会改变。它包含边框、图像和其他格式。

【参考方案1】：

您需要以下 Java 库和相关的 JAR 文件才能使程序运行。 POI v3.8 iText v5.3.4

试试这个例子把 XLS 转换成 PDF

下面提供了接受 Excel 电子表格数据作为输入并将其转换为 PDF 表格数据的完整 Java 代码：

 import java.io.FileInputStream;
    import java.io.*;
    import org.apache.poi.hssf.usermodel.HSSFWorkbook;
    import org.apache.poi.hssf.usermodel.HSSFSheet;
    import org.apache.poi.ss.usermodel.*;
    import java.util.Iterator;
   import com.itextpdf.text.*;
    import com.itextpdf.text.pdf.*;

    public class excel2pdf   
            public static void main(String[] args) throws Exception

                    FileInputStream input_document = new FileInputStream(new File("C:\\excel_to_pdf.xls"));
                    // Read workbook into HSSFWorkbook
                    HSSFWorkbook my_xls_workbook = new HSSFWorkbook(input_document); 
                    // Read worksheet into HSSFSheet
                    HSSFSheet my_worksheet = my_xls_workbook.getSheetAt(0); 
                    // To iterate over the rows
                    Iterator<Row> rowIterator = my_worksheet.iterator();
                    //We will create output PDF document objects at this point
                    Document iText_xls_2_pdf = new Document();
                    PdfWriter.getInstance(iText_xls_2_pdf, new FileOutputStream("Excel2PDF_Output.pdf"));
                    iText_xls_2_pdf.open();
                    //we have two columns in the Excel sheet, so we create a PDF table with two columns
                    //Note: There are ways to make this dynamic in nature, if you want to.
                    PdfPTable my_table = new PdfPTable(2);
                    //We will use the object below to dynamically add new data to the table
                    PdfPCell table_cell;
                    //Loop through rows.
                    while(rowIterator.hasNext()) 
                            Row row = rowIterator.next(); 
                            Iterator<Cell> cellIterator = row.cellIterator();
                                    while(cellIterator.hasNext()) 
                                            Cell cell = cellIterator.next(); //Fetch CELL
                                            switch(cell.getCellType())  //Identify CELL type
                                                    //you need to add more code here based on
                                                    //your requirement / transformations
                                            case Cell.CELL_TYPE_STRING:
                                                    //Push the data from Excel to PDF Cell
                                                     table_cell=new PdfPCell(new Phrase(cell.getStringCellValue()));
                                                     //feel free to move the code below to suit to your needs
                                                     my_table.addCell(table_cell);
                                                    break;
                                            
                                            //next line
                                    

                    
                    //Finally add the table to PDF document
                    iText_xls_2_pdf.add(my_table);                       
                    iText_xls_2_pdf.close();                
                    //we created our pdf file..
                    input_document.close(); //close xls
            
    

希望对你有帮助

【讨论】：

面临这个问题：提供的数据似乎在 Office 2007+ XML 中。您正在调用处理 OLE2 Office 文档的 POI 部分。您需要调用 POI 的不同部分来处理这些数据（例如 XSSF 而不是 HSSF）

【参考方案2】：

另一种方法是使用 VB 脚本并从 Java 中调用它。

例子：

xl2pdf.vbs

Option Explicit
Dim objExcel, strExcelPath, objSheet

strExcelPath = "$XL_FILE"

Set objExcel = CreateObject("Excel.Application")
objExcel.WorkBooks.Open strExcelPath
Set objSheet = objExcel.ActiveWorkbook.Worksheets(1)

objSheet.ExportAsFixedFormat 0, "$PDF_FILE",0, 1, 0, , , 0

objExcel.ActiveWorkbook.Close
objExcel.Application.Quit

在 Java 中（实际上是 kotlin，但易于翻译）

fun xl2pdf(xlFile: Path, pdfFile: Path, timeout: Long = 1, timeUnit: TimeUnit = TimeUnit.MINUTES) 
  val tempScript = Files.createTempFile("script", ".vbs")
  val script = Files.readAllLines(Paths.get("xl2pdf.vbs"))
          .map  it.replace("\$XL_FILE", "$xlFile") 
          .map  it.replace("\$PDF_FILE", "$pdfFile") 
  Files.write(tempScript, script)
  try 
    val pb = ProcessBuilder("wscript", tempScript.toString())
    val process = pb.start()
    val success = process.waitFor(timeout, timeUnit)
    if (!success) LOG.error("Could not print PDF within $timeout $timeUnit")
   catch (e: IOException) 
    LOG.error("Error while printing Excel file to PDF", e)
  

【参考方案3】：

添加到 assylias 的答案

上面来自 assylias 的代码对我解决这个问题很有帮助。如果您不关心生成的 PDF 看起来与您的 excel pdf 导出的外观完全相同，那么来自 santhosh 的答案可能会很棒。但是，如果您使用 Apache POI 填写一个 excel 模板，然后尝试导出该模板，同时保留其外观，而不是在 iText 中编写大量代码只是为了接近该外观，那么 VBS 选项是很不错。

我将分享上面的 kotlin assylias 的 Java 版本，以防对任何人有所帮助。解决方案的一般形式都归功于 assylias。

在 Java 中：

try 
    //create a temporary file and grab the path for it
    Path tempScript = Files.createTempFile("script", ".vbs");

    //read all the lines of the .vbs script into memory as a list
    //here we pull from the resources of a Gradle build, where the vbs script is stored
    System.out.println("Path for vbs script is: '" + Main.class.getResource("xl2pdf.vbs").toString().substring(6) + "'");
    List<String> script = Files.readAllLines(Paths.get(Main.class.getResource("xl2pdf.vbs").toString().substring(6)));

    // append test.xlsm for file name. savePath was passed to this function
    String templateFile = savePath + "\\test.xlsm";
    templateFile = templateFile.replace("\\", "\\\\");
    String pdfFile = savePath + "\\test.pdf";
    pdfFile = pdfFile.replace("\\", "\\\\");
    System.out.println("templateFile is: " + templateFile);
    System.out.println("pdfFile is: " + pdfFile);

    //replace the placeholders in the vbs script with the chosen file paths
    for (int i = 0; i < script.size(); i++) 
        script.set(i, script.get(i).replaceAll("XL_FILE", templateFile));
        script.set(i, script.get(i).replaceAll("PDF_FILE", pdfFile));
        System.out.println("Line " + i + " is: " + script.get(i));
    

    //write the modified code to the temporary script
    Files.write(tempScript, script);

    //create a processBuilder for starting an operating system process
    ProcessBuilder pb = new ProcessBuilder("wscript", tempScript.toString());

    //start the process on the operating system
    Process process = pb.start();

    //tell the process how long to wait for timeout
    Boolean success = process.waitFor(timeout, minutes);
    if(!success) 
        System.out.println("Error: Could not print PDF within " + timeout + minutes);
     else 
        System.out.println("Process to run visual basic script for pdf conversion succeeded.");
    
    
 catch (Exception e) 
    e.printStackTrace();
    Alert saveAsPdfAlert = new Alert(AlertType.ERROR);
    saveAsPdfAlert.setTitle("ERROR: Error converting to pdf.");
    saveAsPdfAlert.setHeaderText("Exception message is:");
    saveAsPdfAlert.setContentText(e.getMessage());
    saveAsPdfAlert.showAndWait();  

VBS：

Option Explicit
Dim objExcel, strExcelPath, objSheet

strExcelPath = "XL_FILE"


Set objExcel = CreateObject("Excel.Application")
objExcel.WorkBooks.Open strExcelPath
Set objSheet = objExcel.ActiveWorkbook.Worksheets(1)

objSheet.ExportAsFixedFormat 0, "PDF_FILE",0, 1, 0, , , 0

objExcel.ActiveWorkbook.Close
objExcel.Application.Quit

【参考方案4】：

这是完整的工作示例

依赖关系：

compile 'com.itextpdf:itextpdf:5.5.13.2'
compile 'org.apache.poi:poi-ooxml:5.0.0'

Java 代码：

import java.io.*;
import org.apache.poi.ss.usermodel.*;

import java.util.Iterator;
import com.itextpdf.text.*;
import com.itextpdf.text.pdf.*;

public class Excel2PDF 
    public static void main(String[] args) throws Exception 

        Workbook my_xls_workbook = WorkbookFactory.create(new File("/Users/harshad/Desktop/excel.xlsx"));

        Sheet my_worksheet = my_xls_workbook.getSheetAt(0);

        short availableColumns = my_worksheet.getRow(0).getLastCellNum();
        System.out.println("Available columns : " + availableColumns);

        Iterator<Row> rowIterator = my_worksheet.iterator();

        Document iText_xls_2_pdf = new Document();
        PdfWriter.getInstance(iText_xls_2_pdf, new FileOutputStream("/Users/harshad/Desktop/excel.pdf"));
        iText_xls_2_pdf.open();

        PdfPTable my_table = new PdfPTable(availableColumns);

        PdfPCell table_cell = null;

        while (rowIterator.hasNext()) 
            Row row = rowIterator.next();
            Iterator<Cell> cellIterator = row.cellIterator();

            while (cellIterator.hasNext()) 
                Cell cell = cellIterator.next();

                switch (cell.getCellType()) 
                    default:
                        try 
                            table_cell = new PdfPCell(new Phrase(cell.getStringCellValue()));
                         catch (IllegalStateException illegalStateException) 
                            //TODO: Need to handle exceptions for different type too
                            if (illegalStateException.getMessage().equals("Cannot get a STRING value from a NUMERIC cell")) 
                                table_cell = new PdfPCell(new Phrase(String.valueOf(cell.getNumericCellValue())));
                            
                        

                        my_table.addCell(table_cell);
                        break;
                
            
        
        iText_xls_2_pdf.add(my_table);
        iText_xls_2_pdf.close();
        my_xls_workbook.close();