#vulnerable code 
                                @Override
    public boolean containsKey(String cacheTitle, K key) {
        boolean result = this.cacheManager.getCache(cacheTitle).containsKey(key);
        return result;
    } 
                            #location 3 
                            #vulnerability type NULL_DEREFERENCE
#fixed code
                                @Override
    public boolean containsKey(String cacheTitle, K key) {
        Cache cache = this.cacheManager.getCache(cacheTitle);
        if (cache == null) {
            return false;
        }
        boolean result = cache.containsKey(key);
        return result;
    }