private Optional<CollectorFactory> findFactoryFor(Type containerType) {
        Optional<CollectorFactory> entry = factoryCache.get(containerType);
        if (entry != null) {
            return entry;
        }
        entry = factories.stream()
                .filter(f -> f.accepts(containerType))
                .findFirst();
        factoryCache.putIfAbsent(containerType, entry);
        return entry;
    }
Returns the element type for the given container type.

@param containerType the container type.
@return the element type for the given container type, if available.
core/src/main/java/org/jdbi/v3/core/collector/JdbiCollectors.java