#vulnerable code 
                              public String saveCapture(String name, Region reg) {
    ScreenImage img;
    if (reg == null) {
      img = userCapture("Capture for image " + name);
    } else {
      img = capture(reg);
    }
    img.saveInBundle(name);
    return name;
  } 
                            #location 8 
                            #vulnerability type NULL_DEREFERENCE
#fixed code
                              public String saveCapture(String name, Region reg) {
    ScreenImage img;
    if (reg == null) {
      img = userCapture("Capture for image " + name);
    } else {
      img = capture(reg);
    }
    if (img == null) {
      return null;
    } else {
      return img.saveInBundle(name);
    }
  }