Wanted but not invoked mockito test

Question

I want to test the following method, and verify

fi.write( file ) ;

gets executed.

@RequestMapping(value="UploadServlet", method=RequestMethod.POST)
public String uploadfile(HttpServletRequest request, HttpServletResponse response, HttpSession session ) throws IOException{
    filePath = "C:\\JavaWorkspace\\justbuyit\\src\\main\\webapp\\resources\\images\\";
      // maximum size that will be stored in memory
      factory.setSizeThreshold(maxMemSize);
      // Location to save data that is larger than maxMemSize.
      factory.setRepository(largefile);

      // maximum file size to be uploaded.
      upload.setSizeMax( maxFileSize );

      try{ 
      // Parse the request to get file items.
      List fileItems = upload.parseRequest(request);

      // Process the uploaded file items
      Iterator i = fileItems.iterator();

      while ( i.hasNext () ) 
      {
         FileItem fi = (FileItem)i.next();
         if ( !fi.isFormField () )  
         {
            // Get the uploaded file parameters
            String fileName = fi.getName();   
            // Write the file
            if( fileName.lastIndexOf("\\") >= 0 ){
               file = new File( filePath + 
               fileName.substring( fileName.lastIndexOf("\\"))) ;
            }else{
               file = new File( filePath + 
               fileName.substring(fileName.lastIndexOf("\\")+1)) ;
            }
            session.setAttribute("filepath","resources/images/"+fileName.substring(fileName.lastIndexOf("\\")+1) );
            fi.write( file ) ;
            request.setAttribute("filewritten", true);
            request.setAttribute("filename", fileName.substring(fileName.lastIndexOf("\\")+1));
         }
      }
   }catch(Exception ex) {
       System.out.println(ex);
   }

    return "addProduct";
   }

public void setFactory(DiskFileItemFactory factory) {
    this.factory = factory;
}

public void setUpload(ServletFileUpload upload) {
    this.upload = upload;
}

I wrote the following test in mockito:

@Before

public void setUp(){

    MockitoAnnotations.initMocks(this);


    uController = new UploadController();
}

@Test

public void testWriteCommandGetsExecutes() throws Exception{


    uController.setFactory(factory);
    uController.setUpload(upload);
    when(i.hasNext()).thenReturn(false);
    when((FileItem)i.next()).thenReturn(fi);
    when(fi.isFormField()).thenReturn(false);
    uController.uploadfile(request, response, session);
    verify(fi).write(file);
}}

However I get error

wanted but not invoked: fi.write( file ) 

In my coverage this line shows up as yellow:

while ( i.hasNext () ) 

What is the problem?

Answer 1

As David Perez Cabrera and striker mentioned in the comments, it looks like you'll want your block to return true and then false. Mockito supports a couple of syntax choices for this, so either of these should work:

when(i.hasNext()).thenReturn(true, false);

or

when(i.hasNext()).thenReturn(true).thenReturn(false);

For future reference, Mockito's behavior is to do the actions in order and then forever repeat the last one, which means that calls to hasNext stubbed above will return true , false , false , false and so on as opposed to true , false , true , false , true and so on.