ch.epfl.dedis.byzcoin.contracts

Class NamingInstance

java.lang.Object

ch.epfl.dedis.byzcoin.contracts.NamingInstance

public class NamingInstance
extends Object

NamingInstance is represents an instance that can be used to give names to instance IDs. This instance is a singleton on ByzCoin just like the config instance.

Field Summary

Fields

Modifier and Type	Field and Description
static String	ContractId

Constructor Summary

Constructors

Constructor and Description
NamingInstance(ByzCoinRPC bc, DarcId darcID, List<Signer> signers, List<Long> signerCtrs) Create a naming instance.

Method Summary

Modifier and Type	Method and Description
static NamingInstance	fromByzcoin(ByzCoinRPC bc) Loads the singleton naming instance from ByzCoin.
void	remove(String instanceName, InstanceId iID, List<Signer> signers, List<Long> signerCtrs) This method asynchronously removes an instance name.
void	removeAndWait(String instanceName, InstanceId iID, List<Signer> signers, List<Long> signerCtrs, int wait) This method removes an instance name and then waits for confirmation.
InstanceId	resolve(DarcId dID, String name) Resolves a previously named instance ID from a darc ID and a name.
void	set(String instanceName, InstanceId iID, List<Signer> signers, List<Long> signerCtrs) Asynchronously assigns a name to an instance ID.
void	setAndWait(String instanceName, InstanceId iID, List<Signer> signers, List<Long> signerCtrs, int wait) Assigns a name to an instance ID and wait for confirmation.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

ContractId

public static String ContractId

Constructor Detail

NamingInstance

public NamingInstance(ByzCoinRPC bc,
                      DarcId darcID,
                      List<Signer> signers,
                      List<Long> signerCtrs)
               throws CothorityException

Create a naming instance. Note that the naming instance is a singleton.

Parameters:

bc - is a running byzcoin service

darcID - is the darc that contains the "spawn:naming" rule, usually it is the genesis darc

signers - is a list of signers that holds the keys to the "_name" rule in the Darc the guards iID

signerCtrs - is the list of monotonically increasing counters that will go into the instruction, they must match the signers who will eventually sign the instruction

Throws:

CothorityException - if the instance cannot be created

Method Detail

fromByzcoin

public static NamingInstance fromByzcoin(ByzCoinRPC bc)
                                  throws CothorityNotFoundException,
                                         CothorityCommunicationException,
                                         CothorityCryptoException

Loads the singleton naming instance from ByzCoin.

Parameters:

bc - is a running ByzCoin service

Returns:

a reference to the instance

Throws:

CothorityNotFoundException - if the instance cannot be found on ByzCoin, perhaps an old version that does not support naming is used

CothorityCommunicationException - if there is a communication error

CothorityCryptoException - if result that we got back form ByzCoin contains a wrong proof

set

public void set(String instanceName,
                InstanceId iID,
                List<Signer> signers,
                List<Long> signerCtrs)
         throws CothorityException

Asynchronously assigns a name to an instance ID. After the instance is named, ByzCoin.resolveInstanceID can be used to resolve the name. Once set, the name or instance ID cannot be changed. It is not allowed to set a name that was previously removed.

Parameters:

instanceName - is the name given to the instance ID

iID - is the to-be-named instance ID

signers - is a list of signers that holds the keys to the "_name" rule in the Darc the guards iID

signerCtrs - is the list of monotonically increasing counters that will go into the instruction, they must match the signers who will eventually sign the instruction

Throws:

CothorityException - if any error occurs

setAndWait

public void setAndWait(String instanceName,
                       InstanceId iID,
                       List<Signer> signers,
                       List<Long> signerCtrs,
                       int wait)
                throws CothorityException

Assigns a name to an instance ID and wait for confirmation. After the instance is named, ByzCoin.resolveInstanceID can be used to resolve the name. Once set, the name or instance ID cannot be changed. It is not allowed to set a name that was previously removed.

Parameters:

instanceName - is the name given to the instance ID

iID - is the to-be-named instance ID

signers - is a list of signers that holds the keys to the "_name" rule in the Darc the guards iID

signerCtrs - is the list of monotonically increasing counters that will go into the instruction, they must match the signers who will eventually sign the instruction

wait - how many blocks to wait for inclusion of the transaction

Throws:

CothorityException - if any error occurs

remove

public void remove(String instanceName,
                   InstanceId iID,
                   List<Signer> signers,
                   List<Long> signerCtrs)
            throws CothorityException

This method asynchronously removes an instance name. Once removed, the name cannot be used in set again.

Parameters:

instanceName - is the name of the instance to remove

iID - is instance ID which must have been named previously to instanceName

signers - is a list of signers that holds the keys to the "_name" rule in the Darc the guards iID

signerCtrs - is the list of monotonically increasing counters that will go into the instruction, they must match the signers who will eventually sign the instruction

Throws:

CothorityException

removeAndWait

public void removeAndWait(String instanceName,
                          InstanceId iID,
                          List<Signer> signers,
                          List<Long> signerCtrs,
                          int wait)
                   throws CothorityException

This method removes an instance name and then waits for confirmation. Once removed, the name cannot be used in set again.

Parameters:

instanceName - is the name of the instance to remove

iID - is instance ID which must have been named previously to instanceName

signers - is a list of signers that holds the keys to the "_name" rule in the Darc the guards iID

signerCtrs - is the list of monotonically increasing counters that will go into the instruction, they must match the signers who will eventually sign the instruction

wait - how many blocks to wait for inclusion of the transaction

Throws:

CothorityException

resolve

public InstanceId resolve(DarcId dID,
                          String name)
                   throws CothorityCommunicationException

Resolves a previously named instance ID from a darc ID and a name.

Parameters:

dID - is the darc ID that guards the instance.

name - is the name given to the instance when it was named.

Returns:

the instance ID.

Throws:

CothorityCommunicationException - if the name does not exist or other failures.