When migrating to Struts2 2.3.14.2, Stream result doesn't work anymore

Question

After updating to struts2-core-2.3.14.2, it gives me the following error during a download with Stream result:

Stacktrace

Servlet.service() for servlet         


        

Answer 1

It seems fine except that for a couple of things:

1. Specify the contentType:

   <result name="success" type="stream">
      <param name="contentType">text/plain</param>
      <param name="contentDisposition">attachment;filename="${fileName}"</param>
      <param name="inputName">downloadFile</param>
   </result>
   

   text/plain is the default, and in your example you have a txt file, but it is better to explicit it in the configuration;

2. Follow the JavaBeans Conventions; a getter should not have logic, and the name should match the one of the private variable returned:

   For example,

   String foo;
   public String getBar(){ 
       return this.foo; 
   }
   

   is not valid and may cause problems to Struts2 (that makes use of Reflection internally)

   Then try changing your Action code like this:

   String filePathName="/home/download/aaa.txt";
   String fileName;
   InputStream donwloadFile;
   
   public String getFileName() {
      return this.fileName;
   }
   
   public InputStream getDownloadFile() {
       return this.downloadFile;
   }
   
   public String download() throws Exception {
      File file = new File(filePathName);       
      this.fileName = file.getName();
      this.downloadFile = new BufferedInputStream(new FileInputStream(file));
      return SUCCESS;
   }