SubscriptionBase (prosys-opc-ua-sdk-client-server-pubsub 5.6.2-227 API)

java.lang.Object
- com.prosysopc.ua.SubscriptionBase

All Implemented Interfaces:

Comparable<SubscriptionBase>

Direct Known Subclasses:

Subscription, Subscription
```
public abstract class SubscriptionBase
extends Object
implements Comparable<SubscriptionBase>
```
Base class for an OPC UA Subscription.

Field Summary

Fields
Modifier and Type	Field and Description
`protected Map<UnsignedInteger,MonitoredItemBase>`	`items`
`protected long`	`lifetimeCount`
`protected long`	`maxKeepAliveCount`
`protected int`	`maxNotificationsPerPublish`
`protected int`	`priority`
`protected boolean`	`publishingEnabled`
`protected double`	`publishingInterval`
`protected int`	`updateCount`

Constructor Summary

Constructors
Constructor and Description
`SubscriptionBase(UnsignedInteger id, boolean publishingEnabled, double publishingInterval, long lifetimeCount, long maxKeepAliveCount, int maxNotificationsPerPublish, int priority)`
`SubscriptionBase(UnsignedInteger id, Boolean publishingEnabled, Double publishingInterval, UnsignedInteger lifetimeCount, UnsignedInteger maxKeepAliveCount, UnsignedInteger maxNotificationsPerPublish, UnsignedByte priority)`

Method Summary

All Methods Instance Methods Abstract Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`addItem(MonitoredItemBase item, UnsignedInteger itemId)` Add a new monitoring item to the subscription.
`protected void`	`applyUpdates()` Apply the pending modifications guarded by beginUpdate/endUpdate.
`void`	`beginUpdate()` Starts a property or item modification sequence.
`int`	`compareTo(SubscriptionBase s)`
`protected void`	`enabledChanged()` Handles a change in PublishingEnabled
`void`	`endUpdate()` Ends a property or item modification, which was started with `beginUpdate()`.
`MonitoredItemBase`	`getItem(NodeId nodeId)` Find the item that is listening to the specified node.
`MonitoredItemBase`	`getItem(NodeId nodeId, UnsignedInteger attributeId)` Find the item that is listening to the specified node attribute.
`MonitoredItemBase`	`getItem(UnsignedInteger itemId)` Get an item from the subscription.
`int`	`getItemCount()`
`MonitoredItemBase[]`	`getItems()`
`long`	`getLifetimeCount()` The lifetime count should be a mimimum of three times the keep-alive count.
`long`	`getMaxKeepAliveCount()` Max keep alive count defines the number of Publishing Intervals that may pass without any notification being sent.
`int`	`getMaxNotificationsPerPublish()` The maximum number of notifications that the Client wishes to receive in a single Publish response.
`int`	`getPriority()` Indicates the relative priority of the Subscription.
`double`	`getPublishingInterval()` This interval defines the cyclic rate that the Subscription is being requested to return Notifications to the Client.
`UnsignedInteger`	`getSubscriptionId()` The Server-assigned identifier for the Subscription.
`Object`	`getUserData()` Returns a previously `setUserData(Object)` object.
`boolean`	`hasItem(NodeId nodeId)` Checks if the subscription contains an item that is listening to the specified node.
`boolean`	`hasItem(NodeId nodeId, UnsignedInteger attributeId)` Checks if the subscription contains an item that is listening to the specified node attribute.
`boolean`	`hasItem(UnsignedInteger itemId)` Checks if the subscription contains an item with the ID.
`boolean`	`isPublishingEnabled()`
`protected void`	`paramChanged()` Parameter change "event".
`abstract MonitoredItemBase`	`removeItem(MonitoredItemBase item)` Remove an item from the subscription.
`MonitoredItemBase`	`removeItem(UnsignedInteger itemId)` Remove an item from the subscription.
`void`	`setLifetimeCount(long requestedLifetimeCount)` The lifetime count should be a mimimum of three times the keep-alive count.
`void`	`setLifetimeCount(UnsignedInteger requestedLifetimeCount)` The lifetime count shall be a mimimum of three times the keep-alive count.
`void`	`setMaxKeepAliveCount(long requestedMaxKeepAliveCount)` Requested rate of KeepAlive messages.
`void`	`setMaxKeepAliveCount(UnsignedInteger requestedMaxKeepAliveCount)` Requested rate of KeepAlive messages.
`void`	`setMaxNotificationsPerPublish(long maxNotificationsPerPublish)` The maximum number of notifications that the Client wishes to receive in a single Publish response.
`void`	`setMaxNotificationsPerPublish(UnsignedInteger maxNotificationsPerPublish)` The maximum number of notifications that the Client wishes to receive in a single Notification Message.
`void`	`setPriority(int priority)` Indicates the relative priority of the Subscription.
`void`	`setPriority(UnsignedByte priority)` Indicates the relative priority of the Subscription.
`void`	`setPublishingEnabled(boolean publishingEnabled)` A Boolean parameter with the following values : TRUE publishing is enabled for the Subscription.
`void`	`setPublishingInterval(double requestedPublishingInterval)` This interval defines the cyclic rate that the Subscription is being requested to return Notifications to the Client.
`void`	`setPublishingInterval(long requestedPublishingInterval, TimeUnit timeUnit)`
`protected void`	`setSubscriptionId(UnsignedInteger id)`
`void`	`setUserData(Object userData)` Set a custom data object to this item that can be later retrieved with `getUserData()`.
`String`	`toString()`

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

- Field Detail
  - items
```
protected final Map<UnsignedInteger,MonitoredItemBase> items
```
  - lifetimeCount
```
protected long lifetimeCount
```
  - maxKeepAliveCount
```
protected long maxKeepAliveCount
```
  - maxNotificationsPerPublish
```
protected int maxNotificationsPerPublish
```
  - priority
```
protected int priority
```
  - publishingEnabled
```
protected boolean publishingEnabled
```
  - publishingInterval
```
protected double publishingInterval
```
  - updateCount
```
protected int updateCount
```
- Constructor Detail
  - SubscriptionBase
```
public SubscriptionBase(UnsignedInteger id,
                        boolean publishingEnabled,
                        double publishingInterval,
                        long lifetimeCount,
                        long maxKeepAliveCount,
                        int maxNotificationsPerPublish,
                        int priority)
```
  - SubscriptionBase
```
public SubscriptionBase(UnsignedInteger id,
                        Boolean publishingEnabled,
                        Double publishingInterval,
                        UnsignedInteger lifetimeCount,
                        UnsignedInteger maxKeepAliveCount,
                        UnsignedInteger maxNotificationsPerPublish,
                        UnsignedByte priority)
```
- Method Detail
  - addItem
```
public void addItem(MonitoredItemBase item,
                    UnsignedInteger itemId)
```
    Add a new monitoring item to the subscription.
    
    Parameters:
    
    item -
    
    itemId - The ID to use to map the item in the list. On server side this is the monitoredItemId. On client side it is the clientHandle.
  - beginUpdate
```
public void beginUpdate()
```
    Starts a property or item modification sequence. Use the method to group changes to the subscription or items and avoid several modifySubscription or modifyMonitoredItems calls to the server during the edits.
    The method must be paired with endUpdate(), preferably with a try-finally block. You can nest several beginUpdate/endUpdate blocks. The final endUpdate will trigger the changes being written to the server using a modifySubscription or modifyMonitoredItems service call.
  - compareTo
```
public int compareTo(SubscriptionBase s)
```
    Specified by:
    
    compareTo in interface Comparable<SubscriptionBase>
  - endUpdate
```
public final void endUpdate()
                     throws ServiceException
```
    Ends a property or item modification, which was started with beginUpdate().
    
    Throws:
    
    ServiceException - if the update fails due to an error in modifySubscription, modifyItems or setMonitoringMode service call to the server. In that case, you can retry by using a new beginUpdate/endUpdate sequence.
  - getItem
```
public MonitoredItemBase getItem(NodeId nodeId)
```
    Find the item that is listening to the specified node.
    
    Parameters:
    
    nodeId - the listened node
    
    Returns:
    
    the respective monitored item or null, if there is no item that is listening to the specified node
  - getItem
```
public MonitoredItemBase getItem(NodeId nodeId,
                                 UnsignedInteger attributeId)
```
    Find the item that is listening to the specified node attribute. Typically, the Variable nodes are monitored for the Value attribute and Object nodes for the EventNotifier attribute.
    
    Parameters:
    
    nodeId - the listened node
    
    attributeId - the attribute
    
    Returns:
    
    the respective monitored item or null, if there is no item that is listening to the specified node attribute
  - getItem
```
public MonitoredItemBase getItem(UnsignedInteger itemId)
                          throws StatusException
```
    Get an item from the subscription.
    
    Parameters:
    
    itemId - the ID of the item. On the client side this is the ClientHandle and on the server side it is the MonitoredItemId.
    
    Returns:
    
    the item
    
    Throws:
    
    StatusException - if the item is not found, with StatusCode=Bad_MonitoredItemIdInvalid
  - getItemCount
```
public int getItemCount()
```
    Returns:
    
    the number of items in the subscription.
  - getItems
```
public MonitoredItemBase[] getItems()
```
    Returns:
  - getLifetimeCount
```
public long getLifetimeCount()
```
    The lifetime count should be a mimimum of three times the keep-alive count.
    When the publishing timer has expired this number of times without a Publish request being available to send a NotificationMessage, then the Subscription will be deleted by the Server.
    
    Returns:
    
    the subscription lifetime count
    
    See Also:
    
    setLifetimeCount(long)
  - getMaxKeepAliveCount
```
public long getMaxKeepAliveCount()
```
    Max keep alive count defines the number of Publishing Intervals that may pass without any notification being sent.
    If the client does not receive any notification message during the interval specified by the MaxKeepAliveCount (plus some tolerance), the subscription can be considered to be at timeout and the client can assume a problem with a connection to the server.
    
    Returns:
    
    the maximum number of PublishingInterval to pass before a new keep alive message is sent.
  - getMaxNotificationsPerPublish
```
public int getMaxNotificationsPerPublish()
```
    The maximum number of notifications that the Client wishes to receive in a single Publish response. A value of zero indicates that there is no limit.
    
    Returns:
    
    the maximum number of notifications in a single publish message
    
    See Also:
    
    setMaxNotificationsPerPublish(long)
  - getPriority
```
public int getPriority()
```
    Indicates the relative priority of the Subscription. When more than one Subscription needs to send Notifications, the Server should dequeue a Publish request to the Subscription with the highest priority number (the bigger the number, the higher the priority). For Subscriptions with equal priority the Server should dequeue Publish requests in a round-robin fashion. When the keep-alive period expires for a Subscription it shall take precedence regardless of its priority, in order to prevent the Subscription from expiring.
    A Client that does not require special priority settings should set this value to zero.
    
    Returns:
    
    the priority of the subscription
    
    See Also:
    
    setPriority(int)
  - getPublishingInterval
```
public double getPublishingInterval()
```
    This interval defines the cyclic rate that the Subscription is being requested to return Notifications to the Client. This interval is expressed in milliseconds.
    The negotiated value for this parameter returned in the response is used as the default sample interval for MonitoredItems assigned to this Subscription.
    The value 0 is invalid.
    
    Returns:
    
    the publishing interval
    
    See Also:
    
    setPublishingInterval(double)
  - getSubscriptionId
```
public UnsignedInteger getSubscriptionId()
```
    The Server-assigned identifier for the Subscription. This identifier shall be unique for the entire Server, not just for the Session, in order to allow the Subscription to be transferred to another Session using the TransferSubscriptions service.
    
    Returns:
    
    the current ID
  - getUserData
```
public Object getUserData()
```
    Returns a previously setUserData(Object) object.
  - hasItem
```
public boolean hasItem(NodeId nodeId)
```
    Checks if the subscription contains an item that is listening to the specified node.
    
    Parameters:
    
    nodeId - the node
    
    Returns:
    
    true if the subscription has an item listening to the node attribute
  - hasItem
```
public boolean hasItem(NodeId nodeId,
                       UnsignedInteger attributeId)
```
    Checks if the subscription contains an item that is listening to the specified node attribute.
    
    Parameters:
    
    nodeId - the node
    
    attributeId - the attribute
    
    Returns:
    
    true if the subscription has an item listening to the node attribute
  - hasItem
```
public boolean hasItem(UnsignedInteger itemId)
```
    Checks if the subscription contains an item with the ID.
    
    Parameters:
    
    itemId - the ID of the item. On the client side this is the ClientHandle and on the server side it is the MonitoredItemId.
    
    Returns:
    
    true if the subscription has an item with the ID.
  - isPublishingEnabled
```
public boolean isPublishingEnabled()
```
    Returns:
    
    true if publishing is currently enabled in the server.
    
    See Also:
    
    setPublishingEnabled(boolean)
  - removeItem
```
public abstract MonitoredItemBase removeItem(MonitoredItemBase item)
                                      throws ServiceException,
                                             StatusException
```
    Remove an item from the subscription.
    
    Parameters:
    
    item - The item to remove.
    
    Returns:
    
    The item that was removed or null, if it was not in the subscription
    
    Throws:
    
    ServiceException - if the (possible) service call to delete the item from the server fails.
    
    StatusException - if the subscription does not contain the item
  - removeItem
```
public MonitoredItemBase removeItem(UnsignedInteger itemId)
                             throws ServiceException,
                                    StatusException
```
    Remove an item from the subscription.
    
    Parameters:
    
    itemId - The ID of the item to remove. In the client side this should be the ClientHandle, but on server side, the MonitoredItemId is used.
    
    Returns:
    
    The item that was removed or null, if there was no such item.
    
    Throws:
    
    ServiceException - if the service call to delete the item from the server fails.
    
    StatusException - if the delete response from the server is bad
  - setLifetimeCount
```
public final void setLifetimeCount(long requestedLifetimeCount)
                            throws ServiceException
```
    The lifetime count should be a mimimum of three times the keep-alive count.
    When the publishing timer has expired this number of times without a Publish request being available to send a NotificationMessage, then the Subscription will be deleted by the Server.
    
    Parameters:
    
    requestedLifetimeCount - The value must be in the range of UnsignedInteger
    
    Throws:
    
    ServiceException - If the parameter could not be changed.
  - setLifetimeCount
```
public void setLifetimeCount(UnsignedInteger requestedLifetimeCount)
                      throws ServiceException
```
    The lifetime count shall be a mimimum of three times the keep-alive count.
    When the publishing timer has expired this number of times without a Publish request being available to send a NotificationMessage, then the Subscription will be deleted by the Server.
    
    Throws:
    
    ServiceException - If the parameter could not be changed.
  - setMaxKeepAliveCount
```
public final void setMaxKeepAliveCount(long requestedMaxKeepAliveCount)
                                throws ServiceException
```
    Requested rate of KeepAlive messages. The lifetime count enables the server to track subscriptions that are alive in Client applications. The lifetime is calculated by multiplying LifeTimeCount by the PublishingInterval. When the publishing timer in the Server has expired this number of times without requiring any NotificationMessage to be sent, the Server sends a keep-alive Message to the Client.
    The value 0 is invalid.
    
    Parameters:
    
    requestedMaxKeepAliveCount - The value must be in the range of UnsignedInteger
    
    Throws:
    
    ServiceException - If the parameter could not be changed.
  - setMaxKeepAliveCount
```
public void setMaxKeepAliveCount(UnsignedInteger requestedMaxKeepAliveCount)
                          throws ServiceException
```
    Requested rate of KeepAlive messages. The KeepAliveCount enables the client to keep track of subscriptions that are alive in the server. The count is multiplied by the PublishingInterval. When the publishing timer in the Server has expired this number of times without requiring any NotificationMessage to be sent, the Subscription sends a keep-alive Message to the Client.
    The value 0 is invalid.
    
    Parameters:
    
    requestedMaxKeepAliveCount -
    
    Throws:
    
    ServiceException - If the parameter could not be changed.
  - setMaxNotificationsPerPublish
```
public final void setMaxNotificationsPerPublish(long maxNotificationsPerPublish)
                                         throws ServiceException
```
    The maximum number of notifications that the Client wishes to receive in a single Publish response. A value of zero indicates that there is no limit.
    
    Parameters:
    
    maxNotificationsPerPublish - The value must be in the range of UnsignedInteger, but if the value is bigger than Integer.MAX_VALUE, Integer.MAX_VALUE will be used instead.
    
    Throws:
    
    ServiceException - If the parameter could not be changed.
  - setMaxNotificationsPerPublish
```
public void setMaxNotificationsPerPublish(UnsignedInteger maxNotificationsPerPublish)
                                   throws ServiceException
```
    The maximum number of notifications that the Client wishes to receive in a single Notification Message. A value of zero indicates that there is no limit.
    
    Parameters:
    
    maxNotificationsPerPublish - If the value is bigger than Integer.MAX_VALUE, Integer.MAX_VALUE will be used instead.
    
    Throws:
    
    ServiceException - If the parameter could not be changed.
  - setPriority
```
public final void setPriority(int priority)
                       throws ServiceException
```
    Indicates the relative priority of the Subscription. When more than one Subscription needs to send Notifications, the Server should dequeue a Publish request to the Subscription with the highest priority number (the bigger the number, the higher the priority). For Subscriptions with equal priority the Server should dequeue Publish requests in a round-robin fashion. When the keep-alive period expires for a Subscription it shall take precedence regardless of its priority, in order to prevent the Subscription from expiring.
    A Client that does not require special priority settings should set this value to zero.
    
    Parameters:
    
    priority - The value must be in the range of UnsignedByte
    
    Throws:
    
    ServiceException - If the parameter could not be changed.
  - setPriority
```
public void setPriority(UnsignedByte priority)
                 throws ServiceException
```
    Indicates the relative priority of the Subscription. When more than one Subscription needs to send Notifications, the Server should dequeue a Publish request to the Subscription with the highest priority number. For Subscriptions with equal priority the Server should dequeue Publish requests in a round-robin fashion. When the keep-alive period expires for a Subscription it shall take precedence regardless of its priority, in order to prevent the Subscription from expiring.
    A Client that does not require special priority settings should set this value to zero.
    
    Parameters:
    
    priority -
    
    Throws:
    
    ServiceException - If the parameter could not be changed.
  - setPublishingEnabled
```
public void setPublishingEnabled(boolean publishingEnabled)
                          throws ServiceException,
                                 StatusException
```
    A Boolean parameter with the following values :
    
    TRUE publishing is enabled for the Subscription.
    FALSE publishing is disabled for the Subscription.
    The value of this parameter does not affect the value of the monitoring mode Attribute of MonitoredItems.
    
    Parameters:
    
    publishingEnabled - the new value to set
    
    Throws:
    
    StatusException - If the parameter could not be changed due to an operation error from the server.
    
    ServiceException - If the parameter could not be changed due to a service call error.
  - setPublishingInterval
```
public void setPublishingInterval(double requestedPublishingInterval)
                           throws ServiceException
```
    This interval defines the cyclic rate that the Subscription is being requested to return Notifications to the Client. This interval is expressed in milliseconds.
    The negotiated value for this parameter returned in the response is used as the default sample interval for MonitoredItems assigned to this Subscription.
    The value 0 is invalid.
    
    Parameters:
    
    requestedPublishingInterval - requested value for the publishing interval in milliseconds
    
    Throws:
    
    ServiceException - If the parameter could not be changed.
  - setPublishingInterval
```
public void setPublishingInterval(long requestedPublishingInterval,
                                  TimeUnit timeUnit)
                           throws ServiceException
```
    Throws:
    
    ServiceException
    
    See Also:
    
    setPublishingInterval(double)
  - setUserData
```
public void setUserData(Object userData)
```
    Set a custom data object to this item that can be later retrieved with getUserData(). This can be used to store business logic object mapping directly in the Subscription. It will be stored using strong reference and equivalent to having the 'volatile' keyword. Set null to remove. This data is not used in Object.equals(Object), Object.hashCode() or toString().
  - toString
```
public String toString()
```
    Overrides:
    
    toString in class Object
  - applyUpdates
```
protected void applyUpdates()
                     throws ServiceException
```
    Apply the pending modifications guarded by beginUpdate/endUpdate.
    
    Throws:
    
    ServiceException
  - enabledChanged
```
protected void enabledChanged()
                       throws ServiceException,
                              StatusException
```
    Handles a change in PublishingEnabled
    
    Throws:
    
    ServiceException
    
    StatusException
  - paramChanged
```
protected void paramChanged()
                     throws ServiceException
```
    Parameter change "event".
    
    Throws:
    
    ServiceException
  - setSubscriptionId
```
protected void setSubscriptionId(UnsignedInteger id)
```
    Parameters:
    
    id -

TRUE	publishing is enabled for the Subscription.
FALSE	publishing is disabled for the Subscription.

Class SubscriptionBase

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

items

lifetimeCount

maxKeepAliveCount

maxNotificationsPerPublish

priority

publishingEnabled

publishingInterval

updateCount

Constructor Detail

SubscriptionBase

SubscriptionBase

Method Detail

addItem

beginUpdate

compareTo

endUpdate

getItem

getItem

getItem

getItemCount

getItems

getLifetimeCount

getMaxKeepAliveCount

getMaxNotificationsPerPublish

getPriority

getPublishingInterval

getSubscriptionId

getUserData

hasItem

hasItem

hasItem

isPublishingEnabled

removeItem

removeItem

setLifetimeCount

setLifetimeCount

setMaxKeepAliveCount

setMaxKeepAliveCount

setMaxNotificationsPerPublish

setMaxNotificationsPerPublish

setPriority

setPriority

setPublishingEnabled

setPublishingInterval

setPublishingInterval

setUserData

toString

applyUpdates

enabledChanged

paramChanged

setSubscriptionId