pt.unl.fct.di.novasys.babel.crdts.state.implementations

Class StatePNCounter

java.lang.Object

pt.unl.fct.di.novasys.babel.crdts.generic.CRDT

pt.unl.fct.di.novasys.babel.crdts.state.generic.StateBasedCRDT

pt.unl.fct.di.novasys.babel.crdts.state.implementations.StatePNCounter

All Implemented Interfaces:

GenericCRDT, StateCRDT

public class StatePNCounter
extends StateBasedCRDT

A delta-based PN counter CRDT. The CRDT has two distinct collections for storing the increments and decrements.

Field Summary

Fields

Modifier and Type	Field and Description
protected ConcurrentMap<ReplicaID,ValueTsPair<IntegerType>>	decs
protected ConcurrentMap<ReplicaID,ValueTsPair<IntegerType>>	incs
static pt.unl.fct.di.novasys.network.ISerializer<StatePNCounter>	serializer A serializer that serializes the CRDT into (and from) a ByteBuf.
static CRDTsTypes	TYPE

Fields inherited from class pt.unl.fct.di.novasys.babel.crdts.state.generic.StateBasedCRDT

state

Fields inherited from class pt.unl.fct.di.novasys.babel.crdts.generic.CRDT

type

Constructor Summary

Constructors

Constructor and Description
StatePNCounter(ReplicaID replicaID) Creates a state-based counter by passing the replica identifier.
StatePNCounter(ReplicaID replicaID, int initialValue) Creates a delta-based counter by passing the replica identifier.
StatePNCounter(VVState state) Creates a state-based counter by passing the current replica state.
StatePNCounter(VVState state, int initialValue) Creates a delta-based counter by passing the current replica state.

Method Summary

Modifier and Type	Method and Description
GenericCRDT	copy() Creates a copy of the CRDT.
void	decrement(int amount) Decrements the value of the counter.
void	increment(int amount) Increments the value of the counter.
StateBasedCRDT	merge(StateBasedCRDT crdt) Handles the merging of this CRDT with other state-based CRDT received from the network.
void	serialize(io.netty.buffer.ByteBuf in) Serializes the CRDT into a ByteBuf
int	value() Gets the value of the counter

Methods inherited from class pt.unl.fct.di.novasys.babel.crdts.state.generic.StateBasedCRDT

getReplicaID, getReplicaState

Methods inherited from class pt.unl.fct.di.novasys.babel.crdts.generic.CRDT

getType

Methods inherited from class java.lang.Object

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

Methods inherited from interface pt.unl.fct.di.novasys.babel.crdts.generic.GenericCRDT

deserializeDataType, getType

Field Detail

TYPE

public static final CRDTsTypes TYPE

incs

protected ConcurrentMap<ReplicaID,ValueTsPair<IntegerType>> incs

decs

protected ConcurrentMap<ReplicaID,ValueTsPair<IntegerType>> decs

serializer

public static pt.unl.fct.di.novasys.network.ISerializer<StatePNCounter> serializer

A serializer that serializes the CRDT into (and from) a ByteBuf.

Constructor Detail

StatePNCounter

public StatePNCounter(ReplicaID replicaID)

Creates a state-based counter by passing the replica identifier. The counter is initialized to zero.

Parameters:

replicaID - replica identifier

StatePNCounter

public StatePNCounter(VVState state)

Creates a state-based counter by passing the current replica state. The counter is initialized to zero.

Parameters:

state - replica state

StatePNCounter

public StatePNCounter(ReplicaID replicaID,
                      int initialValue)

Creates a delta-based counter by passing the replica identifier. The counter is initialized to the passed value.

Parameters:

replicaID - replica identifier

initialValue - the initial value of the counter

StatePNCounter

public StatePNCounter(VVState state,
                      int initialValue)

Creates a delta-based counter by passing the current replica state. The is initialized to the passed value.

Parameters:

state - replica state

initialValue - the initial value of the counter

Method Detail

copy

public GenericCRDT copy()

Description copied from interface: GenericCRDT

Creates a copy of the CRDT. Modifications on the copy don't modify the original.

Returns:

a copy of the CRDT

value

public int value()

Gets the value of the counter

Returns:

the value of the counter

increment

public void increment(int amount)

Increments the value of the counter.

Parameters:

amount - amount to be incremented

decrement

public void decrement(int amount)

Decrements the value of the counter.

Parameters:

amount - amount to be incremented

merge

public StateBasedCRDT merge(StateBasedCRDT crdt)

Description copied from interface: StateCRDT

Handles the merging of this CRDT with other state-based CRDT received from the network. Only the local replica CRDT is updated

Specified by:

merge in interface StateCRDT

Specified by:

merge in class StateBasedCRDT

Parameters:

crdt - the CRDT to merge

Returns:

the newly merged CRDT

serialize

public void serialize(io.netty.buffer.ByteBuf in)
               throws IOException

Description copied from interface: GenericCRDT

Serializes the CRDT into a ByteBuf

Parameters:

in - ByteBuf to serialize the CRDT to

Throws:

IOException - if an error occurs while serializing