ConcurrentMap<String, String> map = cache.asMap();
    map.put(refreshKey, refreshKey);
    assertEquals(1, map.size());
    assertFalse(map.containsKey(getKey));
    assertSame(refreshKey, map.get(refreshKey));

    new Thread() {
      @Override
      public void run() {
        cache.getUnchecked(getKey);

    ConcurrentMap<String, String> map = cache.asMap();
    map.put(refreshKey, refreshKey);
    assertEquals(1, map.size());
    assertFalse(map.containsKey(getKey));
    assertSame(refreshKey, map.get(refreshKey));

    new Thread() {
      @Override
      public void run() {
        cache.getUnchecked(getKey);

type Logger interface {
	LogOnceIf(ctx context.Context, err error, id string, errKind ...interface{})
	LogIf(ctx context.Context, err error, errKind ...interface{})
}

// RefreshKey checks the validity of the KMS Master Key
func (c *kesClient) RefreshKey(ctx context.Context, logger Logger) bool {
	c.lock.RLock()
	defer c.lock.RUnlock()

	validKey := false