java - 如何在java应用程序中创建一个新的excel文件并将其保存在指定位置？

Question

我想创建一个新的 Excel 文件，以便用户在运行时提供文件名，并将该文件保存在用户想要的位置。我尝试了一些代码，但它每次都会在同一位置创建一个具有相同名称的文件。它不会询问用户文件名和位置。

private void buttonCALCULATEActionPerformed(java.awt.event.ActionEvent evt) {
filename="D:\\test.xls" ;
        HSSFWorkbook hwb=new HSSFWorkbook();
        HSSFSheet sheet =  hwb.createSheet("Report in Excel");

        HSSFRow rowhead=sheet.createRow((short)0);
        rowhead.createCell((short) 0).setCellValue("Plot Id");
        rowhead.createCell((short) 1).setCellValue("Species Name");
        FileOutputStream fileOut =  new FileOutputStream(filename);
        hwb.write(fileOut);
        fileOut.close();
        System.out.println("\n Your Excel file has been generated!");
        //String name1=" ";
        FileSave();
 }
public void FileSave() throws IOException
{

JFileChooser chooser=new JFileChooser("./");
FileNameExtensionFilter filter = new  FileNameExtensionFilter("Excel       files",".xls");     
  chooser.addChoosableFileFilter(filter);
  int returnVal1=chooser.showSaveDialog(this);

 // chooser.setFileFilter(filter);
  chooser.setFileSelectionMode(chooser.FILES_ONLY);
  chooser.setDialogTitle("Save File");
  chooser.setCurrentDirectory(new File(System.getProperties().getProperty("user.home")));
  chooser.setFileFilter(new javax.swing.filechooser.FileFilter()
  {
     public boolean accept(final File f)
    {
      return f.isDirectory()|| file.getAbsolutePath().endsWith(".xls");
    }

    public String getDescription(){
      return "Excel files (*.xls)";
    }
  }
);
 if (returnVal1 == JFileChooser.APPROVE_OPTION) 
  {
file1 = chooser.getSelectedFile();       
}
}

Answer 1

将 int returnVal1=chooser.showSaveDialog(this); this 立即放在 if (returnVal1 == JFileChooser.APPROVE_OPTION)

public void FileSave() throws IOException {

    JFileChooser chooser = new JFileChooser("./");
    FileNameExtensionFilter filter = new FileNameExtensionFilter("Excel       files", ".xls");
    chooser.addChoosableFileFilter(filter);

    // chooser.setFileFilter(filter);
    chooser.setFileSelectionMode(chooser.FILES_ONLY);
    chooser.setDialogTitle("Save File");
    chooser.setCurrentDirectory(new File(System.getProperties().getProperty("user.home")));
    chooser.setFileFilter(new javax.swing.filechooser.FileFilter() {
        public boolean accept(final File f) {
            return f.isDirectory() || file.getAbsolutePath().endsWith(".xls");
        }

        public String getDescription() {
            return "Excel files (*.xls)";
        }
    });
    int returnVal1 = chooser.showSaveDialog(this);
    if (returnVal1 == JFileChooser.APPROVE_OPTION) {
        file1 = chooser.getSelectedFile();
    }
}

更改FileSave以返回File(如果用户取消文件选择器，则返回null)

public File FileSave() throws IOException {
    File file1 = null;
    //...
    return file1;
}

在尝试保存文件之前询问文件...

private void buttonCALCULATEActionPerformed(java.awt.event.ActionEvent evt) {
    File file = FileSave();
    if (file != null) {
        HSSFWorkbook hwb = new HSSFWorkbook();
        HSSFSheet sheet = hwb.createSheet("Report in Excel");

        HSSFRow rowhead = sheet.createRow((short) 0);
        rowhead.createCell((short) 0).setCellValue("Plot Id");
        rowhead.createCell((short) 1).setCellValue("Species Name");
        try (FileOutputStream fileOut = new FileOutputStream(file)) {
            hwb.write(fileOut);
        } catch (IOException exp) {
            exp.printStackTrace();
        }
        System.out.println("\n Your Excel file has been generated!");
    }
}

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