org.apache.cassandra.db

Class SinglePartitionReadCommand.Group

java.lang.Object

org.apache.cassandra.db.SinglePartitionReadCommand.Group

All Implemented Interfaces:

ReadQuery

Enclosing class:

SinglePartitionReadCommand

public static class SinglePartitionReadCommand.Group
extends java.lang.Object
implements ReadQuery

Groups multiple single partition read commands.

Field Summary

Fields

Modifier and Type	Field and Description
java.util.List<SinglePartitionReadCommand>	commands

Fields inherited from interface org.apache.cassandra.db.ReadQuery

EMPTY

Constructor Summary

Constructors

Constructor and Description
Group(java.util.List<SinglePartitionReadCommand> commands, DataLimits limits)

Method Summary

Modifier and Type	Method and Description
PartitionIterator	execute(ConsistencyLevel consistency, ClientState clientState, long queryStartNanoTime) Executes the query at the provided consistency level.
PartitionIterator	executeInternal(ReadExecutionController controller) Execute the query for internal queries (that is, it basically executes the query locally).
UnfilteredPartitionIterator	executeLocally(ReadExecutionController executionController) Execute the query locally.
ReadExecutionController	executionController() Starts a new read operation.
QueryPager	getPager(PagingState pagingState, ProtocolVersion protocolVersion) Returns a pager for the query.
DataLimits	limits() The limits for the query.
CFMetaData	metadata()
int	nowInSec()
static SinglePartitionReadCommand.Group	one(SinglePartitionReadCommand command)
boolean	selectsClustering(DecoratedKey key, Clustering clustering)
boolean	selectsFullPartition() Checks if this ReadQuery selects full partitions, that is it has no filtering on clustering or regular columns.
boolean	selectsKey(DecoratedKey key)
java.lang.String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

commands

public final java.util.List<SinglePartitionReadCommand> commands

Constructor Detail

Group

public Group(java.util.List<SinglePartitionReadCommand> commands,
             DataLimits limits)

Method Detail

one

public static SinglePartitionReadCommand.Group one(SinglePartitionReadCommand command)

execute

public PartitionIterator execute(ConsistencyLevel consistency,
                                 ClientState clientState,
                                 long queryStartNanoTime)
                          throws RequestExecutionException

Description copied from interface: ReadQuery

Executes the query at the provided consistency level.

Specified by:

execute in interface ReadQuery

Parameters:

consistency - the consistency level to achieve for the query.

clientState - the ClientState for the query. In practice, this can be null unless consistency is a serial consistency.

Returns:

the result of the query.

Throws:

RequestExecutionException

nowInSec

public int nowInSec()

limits

public DataLimits limits()

Description copied from interface: ReadQuery

The limits for the query.

Specified by:

limits in interface ReadQuery

Returns:

The limits for the query.

metadata

public CFMetaData metadata()

selectsFullPartition

public boolean selectsFullPartition()

Description copied from interface: ReadQuery

Checks if this ReadQuery selects full partitions, that is it has no filtering on clustering or regular columns.

Specified by:

selectsFullPartition in interface ReadQuery

Returns:

true if this ReadQuery selects full partitions, false otherwise.

executionController

public ReadExecutionController executionController()

Description copied from interface: ReadQuery

Starts a new read operation.

This must be called before executeInternal and passed to it to protect the read. The returned object must be closed on all path and it is thus strongly advised to use it in a try-with-ressource construction.

Specified by:

executionController in interface ReadQuery

Returns:

a newly started execution controller for this ReadQuery.

executeInternal

public PartitionIterator executeInternal(ReadExecutionController controller)

Description copied from interface: ReadQuery

Execute the query for internal queries (that is, it basically executes the query locally).

Specified by:

executeInternal in interface ReadQuery

Parameters:

controller - the ReadExecutionController protecting the read.

Returns:

the result of the query.

executeLocally

public UnfilteredPartitionIterator executeLocally(ReadExecutionController executionController)

Description copied from interface: ReadQuery

Execute the query locally. This is similar to ReadQuery.executeInternal(ReadExecutionController) but it returns an unfiltered partition iterator that can be merged later on.

Specified by:

executeLocally in interface ReadQuery

Returns:

the result of the read query.

getPager

public QueryPager getPager(PagingState pagingState,
                           ProtocolVersion protocolVersion)

Description copied from interface: ReadQuery

Returns a pager for the query.

Specified by:

getPager in interface ReadQuery

Parameters:

pagingState - the PagingState to start from if this is a paging continuation. This can be null if this is the start of paging.

protocolVersion - the protocol version to use for the paging state of that pager.

Returns:

a pager for the query.

selectsKey

public boolean selectsKey(DecoratedKey key)

Specified by:

selectsKey in interface ReadQuery

Returns:

true if the read query would select the given key, including checks against the row filter, if checkRowFilter is true

selectsClustering

public boolean selectsClustering(DecoratedKey key,
                                 Clustering clustering)

Specified by:

selectsClustering in interface ReadQuery

Returns:

true if the read query would select the given clustering, including checks against the row filter, if checkRowFilter is true

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object