Class ContinuousQuery<TK, TV>

API for configuring continuous cache queries.

Continuous queries allow to register a remote and a listener for cache update events. If an update event passes the filter, it will be sent to the node that executed the query and listener will be notified on that node.

Continuous query can either be executed on the whole topology or only on local node.

In case query is distributed and a new node joins, it will get the filter for the query during discovery process before it actually joins topology, so no updates will be missed.

To execute the query use method QueryContinuous(ContinuousQuery<TK, TV>).

Inheritance
System.Object
ContinuousQuery
ContinuousQuery<TK, TV>
Inherited Members
Namespace: Apache.Ignite.Core.Cache.Query.Continuous
Assembly: Apache.Ignite.Core.dll
Syntax
public class ContinuousQuery<TK, TV> : ContinuousQuery
Type Parameters
Name Description
TK
TV

Constructors

ContinuousQuery(ICacheEntryEventListener<TK, TV>)

Constructor.

Declaration
public ContinuousQuery(ICacheEntryEventListener<TK, TV> lsnr)
Parameters
Type Name Description
ICacheEntryEventListener<TK, TV> lsnr

Listener.

ContinuousQuery(ICacheEntryEventListener<TK, TV>, ICacheEntryEventFilter<TK, TV>)

Constructor.

Declaration
public ContinuousQuery(ICacheEntryEventListener<TK, TV> lsnr, ICacheEntryEventFilter<TK, TV> filter)
Parameters
Type Name Description
ICacheEntryEventListener<TK, TV> lsnr

Listener.
ICacheEntryEventFilter<TK, TV> filter

Filter.

ContinuousQuery(ICacheEntryEventListener<TK, TV>, ICacheEntryEventFilter<TK, TV>, Boolean)

Constructor.

Declaration
public ContinuousQuery(ICacheEntryEventListener<TK, TV> lsnr, ICacheEntryEventFilter<TK, TV> filter, bool loc)
Parameters
Type Name Description
ICacheEntryEventListener<TK, TV> lsnr

Listener.
ICacheEntryEventFilter<TK, TV> filter

Filter.
System.Boolean loc

Whether query should be executed locally.

ContinuousQuery(ICacheEntryEventListener<TK, TV>, Boolean)

Constructor.

Declaration
public ContinuousQuery(ICacheEntryEventListener<TK, TV> lsnr, bool loc)
Parameters
Type Name Description
ICacheEntryEventListener<TK, TV> lsnr

Listener.
System.Boolean loc

Whether query should be executed locally.

Properties

AutoUnsubscribe

Automatic unsubscribe flag. This flag indicates that query filters on remote nodes should be automatically unregistered if master node (node that initiated the query) leaves topology. If this flag is false, filters will be unregistered only when the query is cancelled from master node, and won't ever be unregistered if master node leaves grid.

Defaults to true.

Declaration
public bool AutoUnsubscribe { get; set; }
Property Value
Type Description
System.Boolean

BufferSize

Buffer size. When a cache update happens, entry is first put into a buffer. Entries from buffer will be sent to the master node only if the buffer is full or time provided via TimeInterval is exceeded.

Defaults to DefaultBufferSize

Declaration
public int BufferSize { get; set; }
Property Value
Type Description
System.Int32

Filter

Optional cache entry filter. Invoked on a node where cache event occurred. If filter returns false, then cache entry event will not be sent to a node where continuous query has been started.

Must be either binary or serializable in case query is not local.

Declaration
public ICacheEntryEventFilter<TK, TV> Filter { get; set; }
Property Value
Type Description
ICacheEntryEventFilter<TK, TV>

IncludeExpired

Gets or sets a value indicating whether to notify about Expired events.

If true, then the remote listener will get notifications about expired cache entries. Otherwise, only Created, Updated, and Removed events will be passed to the listener.

Defaults to false.

Declaration
public bool IncludeExpired { get; set; }
Property Value
Type Description
System.Boolean

Listener

Cache entry event listener. Invoked on the node where continuous query execution has been started.

Declaration
public ICacheEntryEventListener<TK, TV> Listener { get; set; }
Property Value
Type Description
ICacheEntryEventListener<TK, TV>

Local

Local flag. When set query will be executed only on local node, so only local entries will be returned as query result.

Defaults to false.

Declaration
public bool Local { get; set; }
Property Value
Type Description
System.Boolean

TimeInterval

Time interval. When a cache update happens, entry is first put into a buffer. Entries from buffer will be sent to the master node only if the buffer is full (its size can be provided via BufferSize property) or time provided via this method is exceeded.

Defaults to 0 which means that time check is disabled and entries will be sent only when buffer is full.

Declaration
public TimeSpan TimeInterval { get; set; }
Property Value
Type Description
TimeSpan