Program: 69656
Project: 69656
Buggy source:
@Override protected void formOK(UserRequest ureq){
  checkbox.setTitle(titleEl.getValue());
  String releaseKey=releaseEl.getSelectedKey();
  checkbox.setRelease(CheckboxReleaseEnum.valueOf(releaseKey));
  String labelKey=labelEl.getSelectedKey();
  checkbox.setLabel(CheckboxLabelEnum.valueOf(labelKey));
  if (awardPointEl.isAtLeastSelected(1)) {
    Float points=null;
    try {
      points=new Float(Float.parseFloat(pointsEl.getValue()));
    }
 catch (    NumberFormatException e) {
    }
    checkbox.setPoints(points);
  }
 else {
    checkbox.setPoints(null);
  }
  checkbox.setDescription(descriptionEl.getValue());
  if (Boolean.TRUE.equals(deleteFile)) {
    checkbox.setFilename(null);
    ICourse course=CourseFactory.loadCourse(courseOres);
    CourseEnvironment courseEnv=course.getCourseEnvironment();
    VFSContainer container=checkboxManager.getFileContainer(courseEnv,courseNode,checkbox);
    for (    VFSItem chd : container.getItems()) {
      chd.delete();
    }
  }
  File uploadedFile=fileEl.getUploadFile();
  if (uploadedFile != null) {
    String filename=fileEl.getUploadFileName();
    checkbox.setFilename(filename);
    try {
      ICourse course=CourseFactory.loadCourse(courseOres);
      CourseEnvironment courseEnv=course.getCourseEnvironment();
      VFSContainer container=checkboxManager.getFileContainer(courseEnv,courseNode,checkbox);
      VFSLeaf leaf=container.createChildLeaf(filename);
      InputStream inStream=new FileInputStream(uploadedFile);
      VFSManager.copyContent(inStream,leaf);
    }
 catch (    FileNotFoundException e) {
      logError("String_Node_Str",e);
    }
  }
  if (courseNode != null) {
    ILoggingAction action=newCheckbox ? CourseLoggingAction.CHECKLIST_CHECKBOX_CREATED : CourseLoggingAction.CHECKLIST_CHECKBOX_UPDATED;
    ThreadLocalUserActivityLogger.log(action,getClass(),LoggingResourceable.wrap(courseNode),LoggingResourceable.wrapNonOlatResource(StringResourceableType.checkbox,checkbox.getCheckboxId(),checkbox.getTitle()));
  }
  fireEvent(ureq,Event.CHANGED_EVENT);
}

Fixed version (ground truth):
@Override protected void formOK(UserRequest ureq){
  checkbox.setTitle(titleEl.getValue());
  String releaseKey=releaseEl.getSelectedKey();
  checkbox.setRelease(CheckboxReleaseEnum.valueOf(releaseKey));
  String labelKey=labelEl.getSelectedKey();
  checkbox.setLabel(CheckboxLabelEnum.valueOf(labelKey));
  if (awardPointEl.isAtLeastSelected(1)) {
    Float points=null;
    try {
      points=new Float(Float.parseFloat(pointsEl.getValue()));
    }
 catch (    NumberFormatException e) {
    }
    checkbox.setPoints(points);
  }
 else {
    checkbox.setPoints(null);
  }
  checkbox.setDescription(descriptionEl.getValue());
  if (Boolean.TRUE.equals(deleteFile)) {
    checkbox.setFilename(null);
    VFSContainer container=getFileContainer();
    for (    VFSItem chd : container.getItems()) {
      chd.delete();
    }
  }
  File uploadedFile=fileEl.getUploadFile();
  if (uploadedFile != null) {
    String filename=fileEl.getUploadFileName();
    checkbox.setFilename(filename);
    try {
      VFSContainer container=getFileContainer();
      VFSLeaf leaf=container.createChildLeaf(filename);
      InputStream inStream=new FileInputStream(uploadedFile);
      VFSManager.copyContent(inStream,leaf);
    }
 catch (    FileNotFoundException e) {
      logError("String_Node_Str",e);
    }
  }
  if (courseNode != null) {
    ILoggingAction action=newCheckbox ? CourseLoggingAction.CHECKLIST_CHECKBOX_CREATED : CourseLoggingAction.CHECKLIST_CHECKBOX_UPDATED;
    ThreadLocalUserActivityLogger.log(action,getClass(),LoggingResourceable.wrap(courseNode),LoggingResourceable.wrapNonOlatResource(StringResourceableType.checkbox,checkbox.getCheckboxId(),checkbox.getTitle()));
  }
  fireEvent(ureq,Event.CHANGED_EVENT);
}