Wombat::MamaBasicSubscription

The basic subscription supports publish / subscribe. This class can be disposed or the deallocate function called to reduce time during finalization. Note that the deallocate function will attempt to destroy the subscription if this has not already been done whereas dispose will only de-allocate the memory.

Inherits from Wombat.MamaWrapper, IDisposable

Inherited by Wombat.MamaSubscription

Protected Classes

Public Functions

Protected Functions

Public Properties

Protected Attributes

Additional inherited members

Public Functions inherited from Wombat.MamaWrapper

Protected Functions inherited from Wombat.MamaWrapper

Protected Attributes inherited from Wombat.MamaWrapper

Public Functions Documentation

function OnSubscriptionCreateDelegate

delegate void OnSubscriptionCreateDelegate(
    IntPtr nativeHandle,
    IntPtr closure
)

This delegate describes that native callback function that is invoked whenever the subscription has been created.

Parameters:

• nativeHandle The native subscription.
• closure The native closure passed to the create function.

function OnSubscriptionDestroyDelegate

delegate void OnSubscriptionDestroyDelegate(
    IntPtr nativeHandle,
    IntPtr closure
)

This delegate describes the native function invoked whenever the subscription has been either destroyed or deactivated.

Parameters:

• nativeHandle The native subscription.
• closure The native closure passed to the create function.

function OnSubscriptionErrorDelegate

delegate void OnSubscriptionErrorDelegate(
    IntPtr nativeHandle,
    int status,
    IntPtr platformError,
    string subject,
    IntPtr closure
)

This delegate describes the native function invoked if an error occurs during prior to subscription creation or if the subscription receives a message for an un-entitled subject. If the status is MAMA_MSG_STATUS_NOT_ENTITTLED the subject parameter is the specific unentitled subject. If the subscription subject contains wildcards, the subscription may still receive messages for other entitled subjects. Note wildcard subscriptions are not supported on all platforms.

Parameters:

• nativeHandle The native subscription.
• status The associated error code.
• platformError Platform specific error information.
• subject The subject for NOT_ENTITLED errors.
• closure The native closure passed to the create function.

function OnSubscriptionGapDelegate

delegate void OnSubscriptionGapDelegate(
    IntPtr nativeHandle,
    IntPtr closure
)

This delegate describes the native function invoked when a sequence number gap is detected. At this point the topic is considered stale and the subscription will not receive further messages until the feed handler satisfies a recap request.

Parameters:

• nativeHandle The native subscription.
• closure The native closure passed to the create function.

function OnSubscriptionMessageDelegate

delegate void OnSubscriptionMessageDelegate(
    IntPtr nativeHandle,
    IntPtr msg,
    IntPtr closure,
    IntPtr itemClosure
)

This delegate describes the native function that is invoked whenever a message arrives.

Parameters:

• nativeHandle The native subscription.
• msg The native mama message.
• closure The native closure passed to the create function.
• itemClosure The item closure for the subscription can be set with setItemClosure, note that setItemClosure is not provided in the C# implementation.

function OnSubscriptionQualityDelegate

delegate void OnSubscriptionQualityDelegate(
    IntPtr nativeHandle,
    int quality,
    string symbol,
    short cause,
    string platforminfo,
    IntPtr closure
)

This delegate describes the native function invoked to indicate a data quality event.

Parameters:

• nativeHandle The native subscription.
• quality The new quality.
• symbol The symbol.
• cause The cause of the data quality event.
• platforminfo Info associated with the data quality event.
• closure The native closure passed to the create function.

function OnSubscriptionRecapRequestDelegate

delegate void OnSubscriptionRecapRequestDelegate(
    IntPtr nativeHandle,
    IntPtr closure
)

This delegate describes the native function invoked when a recap is requested upon detecting a sequence number gap.

Parameters:

• nativeHandle The native subscription.
• closure The native closure passed to the create function.

function MamaBasicSubscription

MamaBasicSubscription()

Constructor constructs a new basic subscription including creating the underlying native subscription.

function createBasic

void createBasic(
    MamaTransport transport,
    MamaQueue queue,
    MamaBasicSubscriptionCallback callback,
    string symbol
)

This function will create the basic subscription without marketdata semantics. To pass a closure use the overload.

Parameters:

• transport The MamaTransport.
• queue The MamaQueue.
• callback Provide callback function implementations to be informed of events on the subscription.
• symbol The symbol to subscribe to.

function createBasic

void createBasic(
    MamaTransport transport,
    MamaQueue queue,
    MamaBasicSubscriptionCallback callback,
    string symbol,
    object closure
)

This function will create the basic subscription without marketdata semantics.

Parameters:

• transport The MamaTransport.
• queue The MamaQueue.
• callback Provide callback function implementations to be informed of events on the subscription.
• symbol The symbol to subscribe to.
• closure The closure that will be passed back with the callback functions.

function deallocate

void deallocate()

Free the memory for a mamaSubscription which was allocated via a call to constructor. This function will call destroy() if the subscription has not already been destroyed. Calling this function will reduce time during finalization.

function destroy

void destroy()

This function will destroy the subscription, it must be called from the same thread that is processing the queue for the subscription. Use destroyEx to destroy the subscription from any thread. Note that the subscription will not be fully destroyed until the onDestroy callback is received.

function destroyEx

void destroyEx()

Destroy the subscription. This function is another option to destroy the resources associated with the subscription It will schedule the destroy() of the subscription on the queue on which it dispatches. This function does not free the memory associated with the subscription. create() can be called again after this function has been called. After the Subscription is effectively destroyed, the OnDestroy callback will be triggered for it.

This function can be called from any thread, as opposed to destroy().

Protected Functions Documentation

function DestroyNativePeer

virtual override MamaStatus.mamaStatus DestroyNativePeer()

This will be called by the base class to de-allocate the native subscription. MamaWrapper.DestroyNativePeer

Return: MAMA Status code.

Reimplements: Wombat::MamaWrapper::DestroyNativePeer

Public Property Documentation

property State

mamaSubscriptionState State;

This read only property returns the current state of the subscription, this function should be used in preference to the mamaSubscription_isActive or mamaSubscription_isValid functions. function is thread-safe. The state will be one of the mamaSubscriptionState enumeration values.

property subscClosure

object subscClosure;

Read only property returns the closure passed to the create function.

property subscQueue

MamaQueue subscQueue;

Read only property returns the queue.

property subscSymbol

string subscSymbol;

Read only property returns the symbol for this subscription.

Protected Attributes Documentation

variable mClosure

object mClosure;

The closure passed to the create function. This member is declared as protected as there is a public read only property to access it.

variable mQueue

MamaQueue mQueue;

The queue passed to the create function. This member is declared as protected as there is a public read only property to access it.

variable mTransport

MamaTransport mTransport;

The transport passed to the create function. This member is declared as protected as there is a public read only property to access it.

variable mCallbackDelegates

static NativeMethods.SubscriptionCallbacks mCallbackDelegates;

This structure holds all of the callback delegates, it is initialised in the static constructor.

Updated on 2023-03-31 at 15:29:32 +0100