ch.epfl.dedis.lib.omniledger

Class Instruction

java.lang.Object

ch.epfl.dedis.lib.omniledger.Instruction

public class Instruction
extends Object

An instruction is sent and executed by OmniLedger.

Constructor Summary

Constructors

Constructor and Description
Instruction(InstanceId instId, byte[] nonce, int index, int length, Delete delete) Use this constructor if it is a delete instruction, i.e.
Instruction(InstanceId instId, byte[] nonce, int index, int length, Invoke invoke) Use this constructor if it is an invoke instruction, i.e.
Instruction(InstanceId instId, byte[] nonce, int index, int length, Spawn spawn) Use this constructor if it is a spawn instruction, i.e.

Method Summary

Modifier and Type	Method and Description
String	action() Outputs the action of the instruction, this action be the same as an action in the corresponding darc.
InstanceId	deriveId(String what) This function derives an instance ID from the instruction with the given string.
InstanceId	getInstId() Getter for the object ID.
byte[]	hash() This method computes the sha256 hash of the instruction.
void	setSignatures(List<Signature> signatures) Setter for the signatures.
void	signBy(List<Signer> signers) Have a list of signers sign the instruction.
Request	toDarcRequest() Converts the instruction to a Darc request representation.
OmniLedgerProto.Instruction	toProto() Converts this object to the protobuf representation.

Methods inherited from class java.lang.Object

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

Constructor Detail

Instruction

public Instruction(InstanceId instId,
                   byte[] nonce,
                   int index,
                   int length,
                   Spawn spawn)

Use this constructor if it is a spawn instruction, i.e. you want to create a new object.

Parameters:

instId - The ID of the object, which must be unique.

nonce - The nonce of the object.

index - The index of the instruction in the atomic set.

length - The length of the atomic set.

spawn - The spawn object, which contains the value and the argument.

Instruction

public Instruction(InstanceId instId,
                   byte[] nonce,
                   int index,
                   int length,
                   Invoke invoke)

Use this constructor if it is an invoke instruction, i.e. you want to mutate an object.

Parameters:

instId - The ID of the object, which must be unique.

nonce - The nonce of the object.

index - The index of the instruction in the atomic set.

length - The length of the atomic set.

invoke - The invoke object.

Instruction

public Instruction(InstanceId instId,
                   byte[] nonce,
                   int index,
                   int length,
                   Delete delete)

Use this constructor if it is a delete instruction, i.e. you want to delete an object.

Parameters:

instId - The ID of the object, which must be unique.

nonce - The nonce of the object.

index - The index of the instruction in the atomic set.

length - The length of the atomic set.

delete - The delete object.

Method Detail

getInstId

public InstanceId getInstId()

Getter for the object ID.

setSignatures

public void setSignatures(List<Signature> signatures)

Setter for the signatures.

hash

public byte[] hash()

This method computes the sha256 hash of the instruction.

Returns:

The digest.

toProto

public OmniLedgerProto.Instruction toProto()

Converts this object to the protobuf representation.

Returns:

The protobuf representation.

action

public String action()

Outputs the action of the instruction, this action be the same as an action in the corresponding darc. Otherwise this instruction may not be accepted.

Returns:

The action.

toDarcRequest

public Request toDarcRequest()

Converts the instruction to a Darc request representation.

Returns:

The Darc request.

signBy

public void signBy(List<Signer> signers)
            throws CothorityCryptoException

Have a list of signers sign the instruction. The instruction will *not* be accepted by omniledger if it is not signed. The signature will not be valid if the instruction is modified after signing.

Parameters:

signers - - the list of signers.

Throws:

CothorityCryptoException

deriveId

public InstanceId deriveId(String what)
                    throws CothorityCryptoException

This function derives an instance ID from the instruction with the given string. The derived instance ID if useful as a key to this instruction.

Parameters:

what - - the string that gets mixed into the derived instance ID

Returns:

the instance ID

Throws:

CothorityCryptoException