如何在java中保存扩展名为.xls的excel文件？

Question

我必须保存一个带有 .xls 扩展名的 excel 文件。我希望在使用文件选择器设计的保存文件对话框中选择文件类型后，默认情况下应该采用扩展名。我已经尝试了这么多代码但仅当我将文件名指定为 filename.xls 时，它才会以 .xls 格式保存文件

public void FileSave() throws IOException{             

   JFileChooser chooser=new JFileChooser(".");       
   FileNameExtensionFilter filter = new FileNameExtensionFilter("Excel files","xls","excel");       
   chooser.addChoosableFileFilter(filter);      
   chooser.setFileFilter(filter);
   chooser.setFileSelectionMode(chooser.FILES_AND_DIRECTORIES);
   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();

        if(!file1.exists()){
            FileOutputStream fileOut =  new FileOutputStream(file1);
            hwb.write(fileOut);
            fileOut.close();
            System.out.println("\n Your Excel file has been generated!");
            JOptionPane.showMessageDialog(this,"File Created.");
        }
        else if(file1.exists()){
            int res=JOptionPane.showConfirmDialog(this,"File already exists.Do you wish to overwrite?");
            if(res == JOptionPane.YES_OPTION){
                FileOutputStream fileOut =  new FileOutputStream(file1);
                hwb.write(fileOut);
                fileOut.close();
                System.out.println("\n Your Excel file has been generated!");
                JOptionPane.showMessageDialog(this,"File Created.");
            }else if(res == JOptionPane.NO_OPTION){
                int returnVal2=chooser.showSaveDialog(this);
                if (returnVal2 == JFileChooser.APPROVE_OPTION){

                    File file2 = chooser.getSelectedFile();
                    if(!file2.exists()){

                        FileOutputStream fileOut =  new FileOutputStream(file2);
                        hwb.write(fileOut);
                        fileOut.close();
                        System.out.println("\n Your Excel file has been generated!");
                        JOptionPane.showMessageDialog(this,"File Created.");
                    }

                }
            }else if (res == JOptionPane.CANCEL_OPTION){
                JOptionPane.showMessageDialog(this, "User cancelled operation.");
            } 
        }
    }    
}  

Answer 1

您需要使用此选项将文件名设置为*.xls：

chooser.setSelectedFile("*.xls");

对于文件类型下拉菜单，设置以下选项：

JFileChooser chooser = new JFileChooser();
FileNameExtensionFilter filter = new FileNameExtensionFilter("Excel files","xls","excel");       
chooser.addChoosableFileFilter(filter);     
chooser.setFileFilter(filter);
chooser.setAcceptAllFileFilterUsed(false);

Answer 2

我这样做了，它奏效了。

if(!file1.exists())
{
           FileOutputStream fileOut =  new   FileOutputStream(file1+".xls");
           hwb.write(fileOut);
           fileOut.close();
           System.out.println("\n Your Excel file has been generated!");
           JOptionPane.showMessageDialog(this,"File Created.");
}