code: public boolean exists(final File file) {
          if (System.getSecurityManager() == null)
              return file.exists();
          return AccessController.doPrivileged(new PrivilegedAction<Boolean>() {
              @Override
              public Boolean run() {
                  return file.exists() ? Boolean.TRUE : Boolean.FALSE;
              }
          }, controlContext).booleanValue();
      }
docs: Returns true if a file exists, otherwise false is returned. Same as calling
  file.exists().
  
  @param file a file object
  @return true if a file exists, otherwise false