Good catch, but I'd code this like this instead so that you guarantee to close the chunk and ignore any exception that occurs when you close it, as you'd be in the middle of throwing another, different exception:

    boolean success = false;
    try {
        Closeable element = cacheFactory.newCache(cachePtr, chunk);
        getServerCaches().put(cacheId, element);
        success = true;
        return element;
    } finally {
        if (!success) Closeables.closeQuietly(chunk); // com.google.common.io.Closeables
    }