class Blockchain implements Serializable, PersistenceUnitContainer {

    @SuppressWarnings("unchecked")
	public <H extends Object, B> BlockchainPersistenceUnit<H, B> getUnit(BlockchainUnitType type) {
        return (BlockchainPersistenceUnit<H, B>) blockchain.get(type);
    }

    public  Blockchain(BlockchainContext context);

}