#vulnerable code 
                              public void testGetAttemptCount() {
    inv = new AsyncExecution(callable, new RetryPolicy(), scheduler, future, null);
    inv.retryOn(e);
    inv.prepare();
    inv.retryOn(e);
    assertEquals(inv.getExecutions(), 2);
  } 
                            #location 4 
                            #vulnerability type NULL_DEREFERENCE
#fixed code
                              public void testGetAttemptCount() {
    exec = new AsyncExecution(callable, new RetryPolicy(), scheduler, future, null);
    exec.retryOn(e);
    exec.prepare();
    exec.retryOn(e);
    assertEquals(exec.getExecutions(), 2);
  }