#fixed code
                              @Test
  public void testRefreshAfterFailure() throws Exception {
    underTest = new RefreshingOAuth2CredentialsInterceptor(executorService, credentials);

    final AccessToken accessToken = new AccessToken("hi", new Date(HeaderCacheElement.TOKEN_STALENESS_MS + 1));

    //noinspection unchecked
    Mockito.when(credentials.refreshAccessToken())
        // First call will throw Exception & bypass retries
        .thenThrow(new IOException())
        // Second call will succeed
        .thenReturn(accessToken);

    // First call
    HeaderCacheElement firstResult = underTest.getHeaderSafe();
    Assert.assertEquals(CacheState.Exception, firstResult.getCacheState());

    // Now the second token should be available
    HeaderCacheElement secondResult = underTest.getHeaderSafe();
    Assert.assertEquals(CacheState.Good, secondResult.getCacheState());
    Assert.assertThat(secondResult.header, containsString("hi"));
    // Make sure that the token was only requested twice: once for the first failure & second time for background recovery
    Mockito.verify(credentials, times(2)).refreshAccessToken();
  }
#vulnerable code 
                              @Test
  public void testRefreshAfterFailure() throws Exception {
    underTest = new RefreshingOAuth2CredentialsInterceptor(executorService, credentials);
    underTest.rateLimiter.setRate(100000);

    final AccessToken accessToken = new AccessToken("hi", new Date(HeaderCacheElement.TOKEN_STALENESS_MS + 1));

    //noinspection unchecked
    Mockito.when(credentials.refreshAccessToken())
        // First call will throw Exception & bypass retries
        .thenThrow(new IOException())
        // Second call will succeed
        .thenReturn(accessToken);

    // First call
    HeaderCacheElement firstResult = underTest.getHeaderSafe();
    Assert.assertEquals(CacheState.Exception, firstResult.getCacheState());

    // Now the second token should be available
    HeaderCacheElement secondResult = underTest.getHeaderSafe();
    Assert.assertEquals(CacheState.Good, secondResult.getCacheState());
    Assert.assertThat(secondResult.header, containsString("hi"));
    // Make sure that the token was only requested twice: once for the first failure & second time for background recovery
    Mockito.verify(credentials, times(2)).refreshAccessToken();
  } 
                            #location 20 
                            #vulnerability type THREAD_SAFETY_VIOLATION