}

    /**
     * Gets multiple items from the cache based on the given set of keys.
     * <p>
     * @param keys
     * @return a map of K key to ICacheElement&lt;K, V&gt; element, or an empty map if there is no
     *         data in cache for any of these keys
     */
    @Override
    public Map<K, ICacheElement<K, V>> getMultiple(final Set<K> keys)
    {
        if ( keys != null && !keys.isEmpty() )
        {
            return keys.stream()
                .collect(Collectors.toMap(
                        key -> key,
                        this::get)).entrySet().stream()
                    .filter(entry -> entry.getValue() != null)
                    .collect(Collectors.toMap(
                            Entry::getKey,
                            Entry::getValue));
        }

        return new HashMap<>();
    }

    /**
     * Synchronously reads from the lateral cache.
     * <p>
     * @param pattern
     * @return ICacheElement&lt;K, V&gt; if found, else empty
     */
    @Override
    public Map<K, ICacheElement<K, V>> getMatching(final String pattern)
    {

}

        log.debug( "In update, put [{0}] in [{1}]", item::getKey,
                item::getCacheName);
    }

    /**
     * Returns a cache value from the specified remote cache; or null if the cache or key does not
     * exist.
     * <p>
     * @param cacheName
     * @param key
     * @return ICacheElement
     * @throws IOException
     */
    @Override
    public ICacheElement<K, V> get( final String cacheName, final K key )
        throws IOException
    {
        return this.get( cacheName, key, 0 );
    }

    /**
     * Returns a cache bean from the specified cache; or null if the key does not exist.
     * <p>
     * Adding the requestor id, allows the cache to determine the source of the get.
     * <p>
     * The internal processing is wrapped in event logging calls.
     * <p>
     * @param cacheName
     * @param key
     * @param requesterId
     * @return ICacheElement
     * @throws IOException
     */
    @Override
    public ICacheElement<K, V> get( final String cacheName, final K key, final long requesterId )
        throws IOException
    {
        ICacheElement<K, V> element = null;
        final ICacheEvent<K> cacheEvent = createICacheEvent( cacheName, key, requesterId, ICacheEventLogger.GET_EVENT );
        try
        {
            element = processGet( cacheName, key, requesterId );
        }
        finally
        {
            logICacheEvent( cacheEvent );
        }
        return element;
    }

getCacheName(), key);
                log.error("key class={0}", key.getClass());
                log.error("key hashCode={0}", key.hashCode());
                log.error("key toString={0}", key.toString());
                if (key instanceof GroupAttrName)
                {
                    final GroupAttrName<?> name = (GroupAttrName<?>) key;
                    log.error("GroupID hashCode={0}", name.groupId.hashCode());
                    log.error("GroupID.class={0}", name.groupId.getClass());
                    log.error("AttrName hashCode={0}", name.attrName.hashCode());
                    log.error("AttrName.class={0}", name.attrName.getClass());
                }
                dumpMap();
            }
            else if (map.get(key) == null)

@Override
    public Map<K, ICacheElement<K, V>> getMultiple( final String cacheName, final Set<K> keys )
        throws IOException
    {
        return this.getMultiple( cacheName, keys, 0 );
    }

    /**
     * Gets multiple items from the cache based on the given set of keys.
     * <p>
     * The internal processing is wrapped in event logging calls.
     * <p>
     * @param cacheName
     * @param keys
     * @param requesterId
     * @return a map of K key to ICacheElement&lt;K, V&gt; element, or an empty map if there is no
     *         data in cache for any of these keys
     * @throws IOException
     */
    @Override
    public Map<K, ICacheElement<K, V>> getMultiple( final String cacheName, final Set<K> keys, final long requesterId )
        throws IOException
    {
        final ICacheEvent<Serializable> cacheEvent = createICacheEvent( cacheName, (Serializable) keys, requesterId,
                                                    ICacheEventLogger.GETMULTIPLE_EVENT );
        try
        {
            return processGetMultiple( cacheName, keys, requesterId );
        }
        finally
        {
            logICacheEvent( cacheEvent );
        }
    }

@Override
    public Map<K, ICacheElement<K, V>> getMatching( final String cacheName, final String pattern )
        throws IOException
    {
        return getMatching( cacheName, pattern, 0 );
    }

    /**
     * Retrieves all matching keys.
     * <p>
     * @param cacheName
     * @param pattern
     * @param requesterId
     * @return Map of keys and wrapped objects
     * @throws IOException
     */
    @Override
    public Map<K, ICacheElement<K, V>> getMatching( final String cacheName, final String pattern, final long requesterId )
        throws IOException
    {
        final ICacheEvent<String> cacheEvent = createICacheEvent( cacheName, pattern, requesterId,
                                                    ICacheEventLogger.GETMATCHING_EVENT );
        try
        {
            return processGetMatching( cacheName, pattern, requesterId );
        }
        finally
        {
            logICacheEvent( cacheEvent );
        }
    }