commandClass setter methods are not invoked while implementing SimpleFormController in spring 3.x

commandClass setter methods are not invoked while implementing SimpleFormController in spring 3.x, Calling getter method on command odject returns null value.

• uploadMessageBundle.jsp

  <div class="instruction">
      <spring:message code="messagebundle.upload.instruction"/>
  </div>
  
  
  <form method="post" action="uploadMessageBundle.htm" enctype="multipart/form-data">
      <input type="file" name="file"/><br/>
  <spring:bind path="command.locale">
      <select name="${status.expression}">
          <c:forEach var="locale" items="${locales}" varStatus="status">
              <option value="${locale}">${locale}</option>
          </c:forEach>
      </select>
  </spring:bind>
      <br/>
      <table>
          <tr>
              <td class="form_text"></td>
              <td>
                  <input type="submit" name="_target1" class="active" value="<spring:message code='messagebundle.upload'  />"/>
                  <input type="submit" name="_cancel" value="<spring:message code='messagebundle.cancle'/>"/>
              </td>
          </tr>
      </table>
  </form>
  </div>
  <jsp:directive.include file="/templates/footer.jsp"/>
  

• UploadMessageBundleController.java

  package org.sakaiproject.adminmessagebundle.tool;
  
  import org.sakaiproject.messagebundle.api.MessageBundleService;
  import org.sakaiproject.messagebundle.api.MessageBundleProperty;
  import org.apache.poi.hssf.usermodel.HSSFCell;
  import org.apache.poi.hssf.usermodel.HSSFRow;
  import org.apache.poi.hssf.usermodel.HSSFSheet;
  import org.apache.poi.hssf.usermodel.HSSFWorkbook;
  import org.springframework.beans.BeanUtils;
  import org.springframework.validation.BindException;
  import org.springframework.web.bind.ServletRequestDataBinder;
  import org.springframework.web.multipart.support.ByteArrayMultipartFileEditor;
  import org.springframework.web.servlet.ModelAndView;
  
  import javax.servlet.ServletException;
  import javax.servlet.http.HttpServletRequest;
  import javax.servlet.http.HttpServletResponse;
  import java.io.ByteArrayInputStream;
  import java.io.FileInputStream;
  import java.io.InputStream;
  import java.util.*;
  
  public class UploadMessageBundleController extends AbstractUploadController {
  
      MessageBundleService messageBundleService;
  
      protected Map referenceData(HttpServletRequest request) throws Exception {
          Map map = new HashMap();
          map.put("locales",messageBundleService.getLocales());
          return map;
      }
  
      protected void doSubmitAction(Object command) throws Exception {
  
          try {
          setCommandClass(FileUploadBean.class);
          setCommandName("command");
          setSuccessView("messageBundleHome");
          setFormView("uploadMessageBundle");
          FileUploadBean fileUploadBean = (FileUploadBean) command;
          List properties = new ArrayList();
          InputStream myxls = new ByteArrayInputStream(fileUploadBean.getFile());
          HSSFWorkbook wb     = new HSSFWorkbook(myxls);
          HSSFSheet sheet = wb.getSheetAt(0);       // first sheet
          int rows = 0;
          boolean foundHeaderRow = false;
  
          for (Iterator i =sheet.rowIterator();i.hasNext();)
          {
              HSSFRow row = (HSSFRow) i.next();
              if ("module".equals(row.getCell((short)0).getStringCellValue())) {
                  foundHeaderRow = true;
                  continue;
              }
              if (foundHeaderRow) {
                  MessageBundleProperty mbp = new MessageBundleProperty();
                  mbp.setModuleName(row.getCell((short)0).getStringCellValue());
                  mbp.setBaseName(row.getCell((short)1).getStringCellValue());
                  mbp.setPropertyName(row.getCell((short)2).getStringCellValue());
                  mbp.setValue(row.getCell((short)3).getStringCellValue());
                  mbp.setLocale(fileUploadBean.getLocale());
  
                   //TODO allow an optional 5 column for new translations
                  properties.add(mbp);
  
                  rows++;
              }
          }
          if (foundHeaderRow == false) {
              throw new Exception("Invalid excel file, can't find header row");
          }
          fileUploadBean.setRows(messageBundleService.importProperties(properties));
  
          }catch(Exception e) {
  
              e.printStackTrace();
      }
          }
  
      protected ModelAndView onSubmit(HttpServletRequest request, HttpServletResponse response, Object command, BindException errors) throws Exception {
          // when done, redirect to the main page and specify the "command" http parameter
          ModelAndView modelAndView = null;
          FileUploadBean fileUploadBean = (FileUploadBean) command;
          if (isCancel(request)) {
              modelAndView = new ModelAndView(getSuccessView(), "command", "list");
              modelAndView.addObject("msg", "Upload Cancelled");
          } else {
              try {
                  doSubmitAction(command);
                  modelAndView = new ModelAndView(getSuccessView(), "command", "list");
                  modelAndView.addObject("msg", "Upload " + fileUploadBean.getRows() + " properties for locale " + fileUploadBean.getLocale());
              } catch (Exception ex) {
                  modelAndView = new ModelAndView(getSuccessView(), "command", "list");
                  Map model = modelAndView.getModel();
                  model.put("error", ex.getMessage());
                  logger.warn("",ex);
              }
          }
          return modelAndView;
      }
  
      protected void initBinder(HttpServletRequest request, ServletRequestDataBinder binder)
          throws ServletException {
          // to actually be able to convert Multipart instance to byte[]
          // we have to register a custom editor
          binder.registerCustomEditor(byte[].class, new ByteArrayMultipartFileEditor());
          // now Spring knows how to handle multipart object and convert them
      }
  
      public void setMessageBundleService(MessageBundleService messageBundleService) {
          this.messageBundleService = messageBundleService;
      }
  
  }
  

** bean configuration in xml file**

<bean id="uploadMessageBundleController" class="org.sakaiproject.adminmessagebundle.tool.UploadMessageBundleController">
            <property name="messageBundleService"><ref bean="org.sakaiproject.messagebundle.api.MessageBundleService"/></property>
            <property name="commandClass" value="org.sakaiproject.adminmessagebundle.tool.FileUploadBean"/>
            <property name="commandName" value="command"/>
            <property name="formView" value="uploadMessageBundle"/>
            <property name="successView" value="redirect:messageBundleHome.htm"/>
        </bean>

I have missed following bean definition in .xml file, so it was unable to call setter method in commandClass for file uploaded in the form.

<bean id="multipartResolver"
        class="org.springframework.web.multipart.commons.CommonsMultipartResolver" />