java客户端文件的上传和下载

java客户端文件的上传和下载

 //上传
     public JTable upload(String id){
         JTable table=new JTable();
         System.out.println("上传");
         JFileChooser fileChooser=new JFileChooser();
         fileChooser.setDialogTitle("文件上传");
         fileChooser.showOpenDialog(null);
         fileChooser.setVisible(true);
         String srcPath=fileChooser.getSelectedFile().getAbsolutePath();
         System.out.println(srcPath);

         String destFile="contract/"+id+".pdf";
         System.out.println(destFile);
         try{
             FileInputStream in=new FileInputStream(srcPath);
             FileOutputStream out=new FileOutputStream(destFile);
             byte[] buf=new byte[8*1024];
             int b;
             while((b=in.read(buf, 0, buf.length))!=-1){
                 out.write(buf,0,b);
                 out.flush();//最好加上
             }
             System.out.println("上传成功！！");
             in.close();
             out.close();
             //在数据库里更新
             //sql语句肯定是在这边传，因为这边是需求满足
             //直接在数据库里面改数据，在这边刷新数据就可以了
             JOptionPane.showMessageDialog(this,"上传成功");
             table=this.refresh();

         }
         catch (Exception ex3){
             ex3.printStackTrace();
         }
         return table;
     }

上传

 public JTable download(String id){
         System.out.println("下载");

         JTable table=new JTable();

         JFileChooser fileChooser=new JFileChooser();
         fileChooser.setDialogTitle("选择要存放下载文件的位置");
         fileChooser.showOpenDialog(null);
         fileChooser.setVisible(true);
         String destPath=fileChooser.getSelectedFile().getAbsolutePath();
         System.out.println(destPath);

         String endFileName=".pdf";
         if(!destPath.endsWith(endFileName)){
             destPath+=endFileName;
         }

         String srcFile="contract/"+id+".pdf";

         String destFile=destPath;
         System.out.println(destFile);
         try{
             FileInputStream in=new FileInputStream(srcFile);
             FileOutputStream out=new FileOutputStream(destFile);
             byte[] buf=new byte[8*1024];
             int b;
             while((b=in.read(buf, 0, buf.length))!=-1){
                 out.write(buf,0,b);
                 out.flush();//最好加上
             }
             System.out.println("下载成功！！");
             in.close();
             out.close();
             JOptionPane.showMessageDialog(this,"下载成功");
             //下载操作不需要连数据库不需要刷新
             table=this.refresh();
         }
         catch (Exception ex3){
             ex3.printStackTrace();
         }
         return table;
     }

下载