Package convex.core

Class BeliefMerge

java.lang.Object

convex.core.BeliefMerge

public class BeliefMerge
extends Object

Class representing the context to be used for a Belief merge/update function. This context must be created by a Peer to perform a valid Belief merge. It can be safely discarded after use. SECURITY: contains a hot key pair! We need this to sign new belief updates including any chains we want to communicate. Don't allow this to leak anywhere!

Method Summary

Modifier and Type	Method	Description
static boolean	compareOrders(Order oldOrder, Order newOrder)	Checks if a new Order should replace the current order when collecting Peer orders
static <V> double	computeVote(HashMap<V,Double> m)	Computes the total vote for all entries in a HashMap
AVector<SignedData<Block>>	computeWinningOrder(HashMap<Order,Double> stakedOrders, long consensusPoint, double initialTotalStake)	Compute the new winning Order for this Peer, including any new blocks encountered
static BeliefMerge	create(Belief belief, AKeyPair kp, long timestamp, State s)	Create a Belief Merge context
AccountKey	getAccountKey()	Get the address of the current Peer (the one performing the merge)
State	getConsensusState()	Gets the Consensus State for this merge
long	getTimestamp()	Gets the timestamp of this merge
Belief	merge(Belief... beliefs)	The Belief merge function
Belief	mergeOrders(Belief b)	Merge orders from a second Belief
static double	prepareStakedOrders(AMap<AccountKey,SignedData<Order>> peerOrders, HashMap<AccountKey,Double> peerStakes, HashMap<Order,Double> dest)	Compute the total stake for every distinct Order seen.
<T extends ACell> SignedData<T>	sign(T value)	Sign a value using the keypair for this MergeContext
BeliefMerge	withTimestamp(long newTimestamp)	Updates the timestamp of this MergeContext

Methods inherited from class java.lang.Object

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

Method Details

create

public static BeliefMerge create(Belief belief,
 AKeyPair kp,
 long timestamp,
 State s)

Create a Belief Merge context

Parameters:

belief - Initial Belief

kp - Keypair for Belief Merge

timestamp - Timestamp

s - Consensus State

Returns:

New MergeContext instance

merge

public Belief merge(Belief... beliefs)
             throws InvalidDataException

The Belief merge function

Parameters:

beliefs - An array of Beliefs. May contain nulls, which will be ignored.

Returns:

The updated merged belief with latest timestamp, or the same Belief if there is no change to Orders.

Throws:

InvalidDataException - In case of invalid data

mergeOrders

public Belief mergeOrders(Belief b)

Merge orders from a second Belief

Parameters:

b - Belief from which to merge order

Returns:

Belief with updated orders (or the same Belief if unchanged)

prepareStakedOrders

public static double prepareStakedOrders(AMap<AccountKey,SignedData<Order>> peerOrders,
 HashMap<AccountKey,Double> peerStakes,
 HashMap<Order,Double> dest)

Compute the total stake for every distinct Order seen. Stores results in a map of Orders to staked value.

Parameters:

peerOrders - A map of peer addresses to signed proposed Orders

peerStakes - A map of peers addresses to weighted stakes for each peer

dest - Destination hashmap to store the stakes for each Order

Returns:

The total stake of all chains among peers under consideration

computeWinningOrder

public AVector<SignedData<Block>> computeWinningOrder(HashMap<Order,Double> stakedOrders,
 long consensusPoint,
 double initialTotalStake)

Compute the new winning Order for this Peer, including any new blocks encountered

Parameters:

stakedOrders - Amount of stake on each distinct Order

consensusPoint - Current consensus point

initialTotalStake - Total stake under consideration

Returns:

Vector of Blocks in winning Order

computeVote

public static <V> double computeVote(HashMap<V,Double> m)

Computes the total vote for all entries in a HashMap

Type Parameters:

V - The type of values used as keys in the HashMap

Parameters:

m - A map of values to votes

Returns:

The total voting stake

compareOrders

public static boolean compareOrders(Order oldOrder,
 Order newOrder)

Checks if a new Order should replace the current order when collecting Peer orders

Parameters:

oldOrder - Current Order

newOrder - Potential new ORder

Returns:

True if new Order should replace old order

getAccountKey

public AccountKey getAccountKey()

Get the address of the current Peer (the one performing the merge)

Returns:

The Address of the peer.

sign

public <T extends ACell> SignedData<T> sign(T value)

Sign a value using the keypair for this MergeContext

Type Parameters:

T - Type of value

Parameters:

value - Value to sign

Returns:

Signed value

getTimestamp

public long getTimestamp()

Gets the timestamp of this merge

Returns:

Timestamp

withTimestamp

public BeliefMerge withTimestamp(long newTimestamp)

Updates the timestamp of this MergeContext

Parameters:

newTimestamp - New timestamp

Returns:

Updated MergeContext

getConsensusState

public State getConsensusState()

Gets the Consensus State for this merge

Returns:

Consensus State