ch.epfl.dedis.lib.omniledger.contracts

Class DarcInstance

java.lang.Object

ch.epfl.dedis.lib.omniledger.contracts.DarcInstance

public class DarcInstance
extends Object

DarcInstance represents an instance of a darc on Omniledger. It is self- sufficient, meaning it has a link to the omniledger instance it runs on. If you evolve the DarcInstance, it will update its internal darc.

Constructor Summary

Constructors

Constructor and Description
DarcInstance(OmniledgerRPC ol, Darc d)
DarcInstance(OmniledgerRPC ol, InstanceId id) Instantiates a new DarcInstance given a working omniledger instance and an instanceId.

Method Summary

Modifier and Type	Method and Description
TransactionId	evolveDarc(Darc newDarc, Signer owner)
void	evolveDarcAndWait(Darc newDarc, Signer owner) Asks omniledger to evolve the darc and waits until the new darc has been stored in the global state.
Instruction	evolveDarcInstruction(Darc newDarc, Signer owner, int pos, int len) Creates an instruction to evolve the darc in omniledger.
Darc	getDarc()
DarcId	getId()
Instance	getInstance()
TransactionId	spawnContract(String contractID, Signer s, List<Argument> args) Like spawnContractInstruction, but creates a ClientTransaction with only this instruction and sends it to the omniledger.
Proof	spawnContractAndWait(String contractID, Signer s, List<Argument> args, int wait) Like spawnContract but waits for the instance to be stored in omniledger.
Instruction	spawnContractInstruction(String contractID, Signer s, List<Argument> args, int pos, int len) Creates an instruction for spawning a contract.
void	update()

Methods inherited from class java.lang.Object

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

Constructor Detail

DarcInstance

public DarcInstance(OmniledgerRPC ol,
                    InstanceId id)
             throws CothorityException

Instantiates a new DarcInstance given a working omniledger instance and an instanceId. This instantiator will contact omniledger and try to get the current darcInstance. If the instance is not found, or is not of contractId "darc", an exception will be thrown.

Parameters:

ol - is a link to an omniledger instance that is running

id - of the darc-instance to connect to

Throws:

CothorityException

DarcInstance

public DarcInstance(OmniledgerRPC ol,
                    Darc d)
             throws CothorityException

Throws:

CothorityException

Method Detail

update

public void update()
            throws CothorityException

Throws:

CothorityException

evolveDarcInstruction

public Instruction evolveDarcInstruction(Darc newDarc,
                                         Signer owner,
                                         int pos,
                                         int len)
                                  throws CothorityCryptoException

Creates an instruction to evolve the darc in omniledger. The signer must have its identity in the current darc as "Invoke_Evolve" rule.

TODO: allow for evolution if the expression has more than one identity.

Parameters:

newDarc - the darc to replace the old darc.

owner - must have its identity in the "Invoke_Evolve" rule

pos - position of the instruction in the ClientTransaction

len - total number of instructions in the ClientTransaction

Returns:

Instruction to be sent to omniledger

Throws:

CothorityCryptoException

evolveDarc

public TransactionId evolveDarc(Darc newDarc,
                                Signer owner)
                         throws CothorityException

Throws:

CothorityException

evolveDarcAndWait

public void evolveDarcAndWait(Darc newDarc,
                              Signer owner)
                       throws CothorityException

Asks omniledger to evolve the darc and waits until the new darc has been stored in the global state. TODO: check if there has been an error in the transaction!

Parameters:

newDarc - is the new darc to replace the old one

owner - is the owner that can sign to evolve the darc

Throws:

CothorityException

spawnContractInstruction

public Instruction spawnContractInstruction(String contractID,
                                            Signer s,
                                            List<Argument> args,
                                            int pos,
                                            int len)
                                     throws CothorityCryptoException

Creates an instruction for spawning a contract.

TODO: allow for multi-signatures

Parameters:

contractID - the id of the contract to create

s - the signer that is authorized to spawn this contract

args - arguments to give to the contract

pos - position in the ClientTransaction

len - total length of the ClientTransaction

Returns:

the instruction to be added to the ClientTransaction

Throws:

CothorityCryptoException

spawnContract

public TransactionId spawnContract(String contractID,
                                   Signer s,
                                   List<Argument> args)
                            throws CothorityException

Like spawnContractInstruction, but creates a ClientTransaction with only this instruction and sends it to the omniledger.

Parameters:

contractID - the id of the contract to create

s - the signer that is authorized to spawn this contract

args - arguments to give to the contract

Throws:

CothorityException

spawnContractAndWait

public Proof spawnContractAndWait(String contractID,
                                  Signer s,
                                  List<Argument> args,
                                  int wait)
                           throws CothorityException

Like spawnContract but waits for the instance to be stored in omniledger.

Parameters:

contractID - the id of the contract to create

s - the signer that is authorized to spawn this contract

args - arguments to give to the contract

Throws:

CothorityException

getId

public DarcId getId()
             throws CothorityCryptoException

Returns:

the id of the darc being held

Throws:

CothorityCryptoException

getDarc

public Darc getDarc()
             throws CothorityCryptoException

Returns:

a copy of the darc stored in this instance.

Throws:

CothorityCryptoException

getInstance

public Instance getInstance()

Returns:

the instance used.