Interface IDeltaType<TValue, TDelta>

The optional extension provided by IDataType implementations that support incremental changes to values.

Inherited Members

IDeltaType.Name

IDeltaType.WriteDelta(Object, Stream)

IDeltaType.ToBytes(Object)

IDeltaType.Diff(Object, Object)

IDeltaType.Apply(Object, Object)

IDeltaType.IsValueCheaper(Object, Object)

Namespace: PushTechnology.ClientInterface.Data

Assembly: Diffusion.Client.dll

Syntax

public interface IDeltaType<TValue, TDelta> : IDeltaType

Type Parameters

Name	Description
TValue	The value type.
TDelta	The delta type.

Remarks

This is a generic version of the IDeltaType interface that provides overloads for all object methods. It instead provides typed arguments and return values based on the given value and delta type.

For more information about the delta type interface, see IDeltaType.

Since 5.8

Properties

NoChange

Returns a constant that indicates no changes between values.

Declaration

TDelta NoChange { get; }

Property Value

Type	Description
TDelta	A constant that indicates no changes between values.

Remarks

This constant is returned by Diff(TValue, TValue) to indicate oldValue and newValue are equivalent. The result is guaranteed to be equal only to itself.

Methods

Apply(TValue, TDelta)

Applies a delta to a value.

Declaration

TValue Apply(TValue oldValue, TDelta delta)

Parameters

Type	Name	Description
TValue	oldValue	The old value.
TDelta	delta	The delta to apply to the old value.

Returns

Type	Description
TValue	The new value. The old value will be returned if the delta had no effect.

Diff(TValue, TValue)

Creates a delta from two values.

Declaration

TDelta Diff(TValue oldValue, TValue newValue)

Parameters

Type	Name	Description
TValue	oldValue	The old value.
TValue	newValue	The new value.

Returns

Type	Description
TDelta	The delta representing the difference between oldValue and newValue.

Remarks

If there are many differences between oldValue and newValue, the result might require more bytes to transmit than the new value, or be computationally expensive to apply. In this case, it is better to discard oldValue and publish newValue in its place. This can be checked using IsValueCheaper(TValue, TDelta).

The implementation can return the special constant NoChange to indicate the oldValue and newValue are equivalent and there is no change to publish.

IsValueCheaper(TValue, TDelta)

Calculates if value is cheaper than delta. The result is typically determined by the length of the serialized form but can also consider the complexity of the delta.

Declaration

bool IsValueCheaper(TValue value, TDelta delta)

Parameters

Type	Name	Description
TValue	value	The value.
TDelta	delta	The delta.

Returns

Type	Description
System.Boolean	True if value is considered cheaper than delta. Otherwise false.

ReadDelta(IBytes)

Creates a delta from IBytes.

Declaration

TDelta ReadDelta(IBytes input)

Parameters

Type	Name	Description
IBytes	input	The binary data.

Returns

Type	Description
TDelta	The delta object.

Remarks

This is equivalent to calling ReadDelta(Byte[]) with the result of ToByteArray() as argument.

Since 6.0.

ReadDelta(Byte[])

Parses a delta from a binary.

Declaration

TDelta ReadDelta(byte[] input)

Parameters

Type	Name	Description
System.Byte[]	input	The binary data. The implementation may re-use the array to avoid copying. The caller must ensure the array is not modified.

Returns

Type	Description
TDelta	The delta.

Remarks

This is equivalent to ReadDelta(input,0,input.Length).

ReadDelta(Byte[], Int32, Int32)

Parses a delta from a binary segment.

Declaration

TDelta ReadDelta(byte[] input, int offset, int length)

Parameters

Type	Name	Description
System.Byte[]	input	The binary data. The implementation may re-use the array to avoid copying. The caller must ensure the array is not modified.
System.Int32	offset	The starting index of the segment.
System.Int32	length	The length of the segment.

Returns

Type	Description
TDelta	The delta.

ToBytes(TDelta)

Returns the serialized form of the given delta as IBytes.

Declaration

IBytes ToBytes(TDelta delta)

Parameters

Type	Name	Description
TDelta	delta	The delta object.

Returns

Type	Description
IBytes	The delta as IBytes.

Remarks

Since 6.0.

WriteDelta(TDelta, Stream)

Serializes a delta to binary.

Declaration

void WriteDelta(TDelta delta, Stream outputStream)

Parameters

Type	Name	Description
TDelta	delta	The delta.
System.IO.Stream	outputStream	The output stream.