org.gridgain.grid.kernal.processors.cache.query.continuous

Class GridCacheContinuousQueryAdapter<K,V>

java.lang.Object

org.gridgain.grid.kernal.processors.cache.query.continuous.GridCacheContinuousQueryAdapter<K,V>

All Implemented Interfaces:

AutoCloseable, GridCacheContinuousQuery<K,V>

public class GridCacheContinuousQueryAdapter<K,V>
extends Object
implements GridCacheContinuousQuery<K,V>

Continuous query implementation.

Field Summary

Fields inherited from interface org.gridgain.grid.cache.query.GridCacheContinuousQuery

DFLT_AUTO_UNSUBSCRIBE, DFLT_BUF_SIZE, DFLT_TIME_INTERVAL

Method Summary

Methods

Modifier and Type	Method and Description
void	autoUnsubscribe(boolean autoUnsubscribe) Sets automatic unsubscribe flag.
int	bufferSize() Gets buffer size.
void	bufferSize(int bufSize) Sets buffer size.
GridBiPredicate<UUID,Collection<Map.Entry<K,V>>>	callback() Gets local callback.
void	callback(GridBiPredicate<UUID,Collection<Map.Entry<K,V>>> cb) Sets mandatory local callback.
void	close() Stops continuous query execution.
void	execute() Starts continuous query execution on the whole grid.
void	execute(GridProjection prj) Starts continuous query execution on provided set of nodes.
void	execute(GridProjection prj, boolean internal) Starts continuous query execution.
GridBiPredicate<K,V>	filter() Gets key-value filter.
void	filter(GridBiPredicate<K,V> filter) Sets optional key-value filter.
boolean	isAutoUnsubscribe() Gets automatic unsubscribe flag.
long	timeInterval() Gets time interval.
void	timeInterval(long timeInterval) Sets time interval.
String	toString()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Method Detail

callback

public void callback(GridBiPredicate<UUID,Collection<Map.Entry<K,V>>> cb)

Sets mandatory local callback. This callback is called only in local node when new updates are received.

The callback predicate accepts ID of the node from where updates are received and collection of received entries. Note that for removed entries value will be null.

If the predicate returns false, query execution will be cancelled.

WARNING: all operations that involve any kind of JVM-local or distributed locking (e.g., synchronization or transactional cache operations), should be executed asynchronously without blocking the thread that called the callback. Otherwise, you can get deadlocks.

Specified by:

callback in interface GridCacheContinuousQuery<K,V>

Parameters:

cb - Local callback.

callback

@Nullable
public GridBiPredicate<UUID,Collection<Map.Entry<K,V>>> callback()

Gets local callback. See GridCacheContinuousQuery.callback(GridBiPredicate) for more information.

Specified by:

callback in interface GridCacheContinuousQuery<K,V>

Returns:

Local callback.

filter

public void filter(@Nullable
          GridBiPredicate<K,V> filter)

Sets optional key-value filter. This filter is called before entry is sent to the master node.

WARNING: all operations that involve any kind of JVM-local or distributed locking (e.g., synchronization or transactional cache operations), should be executed asynchronously without blocking the thread that called the filter. Otherwise, you can get deadlocks.

Specified by:

filter in interface GridCacheContinuousQuery<K,V>

Parameters:

filter - Key-value filter.

filter

@Nullable
public GridBiPredicate<K,V> filter()

Gets key-value filter. See GridCacheContinuousQuery.filter(GridBiPredicate) for more information.

Specified by:

filter in interface GridCacheContinuousQuery<K,V>

Returns:

Key-value filter.

bufferSize

public void bufferSize(int bufSize)

Sets 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 GridCacheContinuousQuery.timeInterval(long) method is exceeded.

Default buffer size is 1 which means that entries will be sent immediately (buffering is disabled).

Specified by:

bufferSize in interface GridCacheContinuousQuery<K,V>

Parameters:

bufSize - Buffer size.

bufferSize

public int bufferSize()

Gets buffer size. See GridCacheContinuousQuery.bufferSize(int) for more information.

Specified by:

bufferSize in interface GridCacheContinuousQuery<K,V>

Returns:

Buffer size.

timeInterval

public void timeInterval(long timeInterval)

Sets 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 GridCacheContinuousQuery.bufferSize(int) method) or time provided via this method is exceeded.

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

Specified by:

timeInterval in interface GridCacheContinuousQuery<K,V>

Parameters:

timeInterval - Time interval.

timeInterval

public long timeInterval()

Gets time interval. See GridCacheContinuousQuery.timeInterval(long) for more information.

Specified by:

timeInterval in interface GridCacheContinuousQuery<K,V>

Returns:

Gets time interval.

autoUnsubscribe

public void autoUnsubscribe(boolean autoUnsubscribe)

Sets 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.

Default value for this flag is true.

Specified by:

autoUnsubscribe in interface GridCacheContinuousQuery<K,V>

Parameters:

autoUnsubscribe - Automatic unsubscription flag.

isAutoUnsubscribe

public boolean isAutoUnsubscribe()

Gets automatic unsubscribe flag. See GridCacheContinuousQuery.autoUnsubscribe(boolean) for more information.

Specified by:

isAutoUnsubscribe in interface GridCacheContinuousQuery<K,V>

Returns:

Automatic unsubscribe flag.

execute

public void execute()
             throws GridException

Starts continuous query execution on the whole grid.

Note that if grid contains nodes without appropriate cache, these nodes will be filtered out.

Also note that for LOCAL and REPLICATED caches query will be always executed locally.

Specified by:

execute in interface GridCacheContinuousQuery<K,V>

Throws:

GridException - In case of error.

execute

public void execute(@Nullable
           GridProjection prj)
             throws GridException

Starts continuous query execution on provided set of nodes.

Note that if provided projection contains nodes without appropriate cache, these nodes will be filtered out.

Also note that for LOCAL and REPLICATED caches query will be always executed locally.

Specified by:

execute in interface GridCacheContinuousQuery<K,V>

Parameters:

prj - Grid projection.

Throws:

GridException - In case of error.

execute

public void execute(@Nullable
           GridProjection prj,
           boolean internal)
             throws GridException

Starts continuous query execution.

Parameters:

prj - Grid projection.

internal - If true then query notified about internal entries updates.

Throws:

GridException - If failed.

close

public void close()
           throws GridException

Stops continuous query execution.

Note that one query instance can be executed only once. After it's cancelled, it's non-operational. If you need to repeat execution, use GridCacheQueries.createContinuousQuery() method to create new query.

Specified by:

close in interface AutoCloseable

Specified by:

close in interface GridCacheContinuousQuery<K,V>

Throws:

GridException - In case of error.

toString

public String toString()

Overrides:

toString in class Object