org.omg.dds.core.policy

Interface DestinationOrder

All Superinterfaces:

Comparable<DestinationOrder>, DDSObject, QosPolicy, QosPolicy.ForDataReader, QosPolicy.ForDataWriter, QosPolicy.ForTopic, RequestedOffered<DestinationOrder>, Serializable

public interface DestinationOrder
extends QosPolicy.ForTopic, QosPolicy.ForDataReader, QosPolicy.ForDataWriter, RequestedOffered<DestinationOrder>

Controls the criteria used to determine the logical order among changes made by Publisher entities to the same instance of data (i.e., matching Topic and key). The default kind is DestinationOrder.Kind.BY_RECEPTION_TIMESTAMP. Concerns: Topic, DataReader, DataWriter RxO: Yes Changeable: No This policy controls how each subscriber resolves the final value of a data instance that is written by multiple DataWriter objects (which may be associated with different Publisher objects) running on different nodes. The setting DestinationOrder.Kind.BY_RECEPTION_TIMESTAMP indicates that, assuming the Ownership allows it, the latest received value for the instance should be the one whose value is kept. This is the default value. The setting DestinationOrder.Kind.BY_SOURCE_TIMESTAMP indicates that, assuming the Ownership allows it, a time stamp placed at the source should be used. This is the only setting that, in the case of concurrent same-strength DataWriter objects updating the same instance, ensures all subscribers will end up with the same final value for the instance. The mechanism to set the source time stamp is middleware dependent. The value offered is considered compatible with the value requested if and only if the inequality "offered kind >= requested kind" evaluates to true. For the purposes of this inequality, the values of DESTINATION_ORDER kind are considered ordered such that BY_RECEPTION_TIMESTAMP < BY_SOURCE_TIMESTAMP.

See Also:

Ownership

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static class	DestinationOrder.Kind

Nested classes/interfaces inherited from interface org.omg.dds.core.policy.QosPolicy

QosPolicy.ForDataReader, QosPolicy.ForDataWriter, QosPolicy.ForDomainParticipant, QosPolicy.ForDomainParticipantFactory, QosPolicy.ForPublisher, QosPolicy.ForSubscriber, QosPolicy.ForTopic

Method Summary

Methods

Modifier and Type	Method and Description
DestinationOrder.Kind	getKind()
DestinationOrder	withKind(DestinationOrder.Kind kind) Copy this policy and override the value of the property.
DestinationOrder	withReceptionTimestamp()
DestinationOrder	withSourceTimestamp()

Methods inherited from interface org.omg.dds.core.DDSObject

getEnvironment

Methods inherited from interface org.omg.dds.core.policy.RequestedOffered

requestedOfferedContract

Methods inherited from interface java.lang.Comparable

compareTo

Method Detail

getKind

DestinationOrder.Kind getKind()

Returns:

the kind

withKind

DestinationOrder withKind(DestinationOrder.Kind kind)

Copy this policy and override the value of the property.

Returns:

a new policy

withReceptionTimestamp

DestinationOrder withReceptionTimestamp()

Returns:

A new DestinationPolicy with reception timestamp ordering.

withSourceTimestamp

DestinationOrder withSourceTimestamp()

Returns:

A new DestinationPolicy with source timestamp ordering.