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

Class DeltaRGA

java.lang.Object

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

pt.unl.fct.di.novasys.babel.crdts.delta.generic.DeltaBasedCRDT

pt.unl.fct.di.novasys.babel.crdts.delta.implementations.DeltaRGA

All Implemented Interfaces:

DeltaCRDT, GenericCRDT

public class DeltaRGA
extends DeltaBasedCRDT

A delta-based Replicated Growable Array (RGA). Array nodes can be inserted (and removed) through given positions. The array supports generic types implemented as SerializableTypes.

Field Summary

Fields

Modifier and Type	Field and Description
static pt.unl.fct.di.novasys.network.ISerializer<DeltaRGA>	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.delta.generic.DeltaBasedCRDT

state

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

type

Constructor Summary

Constructors

Constructor and Description
DeltaRGA(ReplicaID replicaID) Creates a delta RGA with a given replicaID.
DeltaRGA(ReplicaID replicaID, List<SerializableType> initialValues) Creates a delta RGA with a given replicaID and a list of initial values.
DeltaRGA(VVState state) Creates a delta RGA with a given replica state.
DeltaRGA(VVState state, List<SerializableType> initialValues) Creates a delta RGA with a given replica state and a list of initial values.

Method Summary

Modifier and Type	Method and Description
GenericCRDT	copy() Creates a copy of the CRDT.
DeltaRGA	generateDelta(VersionVector vv) Calculates a delta from a given version for the current state
Iterator<SerializableType>	get() An iterator with all the elements inside the array
SerializableType	getAt(int index) Obtains the element at position index
DeltaRGA	insertAt(int index, SerializableType element) Insert an element into position index
DeltaRGA	mergeDelta(DeltaBasedCRDT crdt) Applies a delta to the current state.
DeltaRGA	removeAt(int index) Removes an element at position index
void	serialize(io.netty.buffer.ByteBuf in) Serializes the CRDT into a ByteBuf

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

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

serializer

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

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

Constructor Detail

DeltaRGA

public DeltaRGA(ReplicaID replicaID)

Creates a delta RGA with a given replicaID.

Parameters:

replicaID - the replica identifier

DeltaRGA

public DeltaRGA(VVState state)

Creates a delta RGA with a given replica state.

Parameters:

state - replica current state

DeltaRGA

public DeltaRGA(ReplicaID replicaID,
                List<SerializableType> initialValues)

Creates a delta RGA with a given replicaID and a list of initial values.

Parameters:

replicaID - the replica identifier

initialValues - the initial values of the CRDT

DeltaRGA

public DeltaRGA(VVState state,
                List<SerializableType> initialValues)

Creates a delta RGA with a given replica state and a list of initial values.

Parameters:

state - replica current state

initialValues - the initial values of the CRDT

Method Detail

insertAt

public DeltaRGA insertAt(int index,
                         SerializableType element)

Insert an element into position index

Parameters:

index - position to insert the element

element - element to be inserted

Returns:

a delta representing the operation

Throws:

IndexOutOfBoundsException - if the index is out of the array bounds

removeAt

public DeltaRGA removeAt(int index)

Removes an element at position index

Parameters:

index - position to insert the element

Returns:

a delta representing the operation

Throws:

IndexOutOfBoundsException - if the index is out of the array bounds

get

public Iterator<SerializableType> get()

An iterator with all the elements inside the array

Returns:

an iterator with all the elements inside the array

getAt

public SerializableType getAt(int index)

Obtains the element at position index

Parameters:

index - the index of the element

Returns:

the element or null if it doesn't exist

Throws:

IndexOutOfBoundsException - if the index is out of the array bounds

generateDelta

public DeltaRGA generateDelta(VersionVector vv)

Description copied from interface: DeltaCRDT

Calculates a delta from a given version for the current state

Specified by:

generateDelta in interface DeltaCRDT

Specified by:

generateDelta in class DeltaBasedCRDT

Parameters:

vv - a version version to calculate the delta from

Returns:

a delta for the current state

mergeDelta

public DeltaRGA mergeDelta(DeltaBasedCRDT crdt)
                    throws CRDTNotValidException

Description copied from interface: DeltaCRDT

Applies a delta to the current state. This method is analogous to a merge of states

Specified by:

mergeDelta in interface DeltaCRDT

Specified by:

mergeDelta in class DeltaBasedCRDT

Parameters:

crdt - a crdt representing the delta

Returns:

the current state

Throws:

CRDTNotValidException - if the crdt passed as argument is invalid

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

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