Package org.apache.iotdb.db.mpp.execution.operator.source

Class LastCacheScanOperator

java.lang.Object

org.apache.iotdb.db.mpp.execution.operator.source.LastCacheScanOperator

All Implemented Interfaces:

java.lang.AutoCloseable, Operator, SourceOperator

public class LastCacheScanOperator
extends java.lang.Object
implements SourceOperator

Field Summary

Fields inherited from interface org.apache.iotdb.db.mpp.execution.operator.Operator

NOT_BLOCKED

Constructor Summary

Constructors

Constructor	Description
LastCacheScanOperator(OperatorContext operatorContext, PlanNodeId sourceId, org.apache.iotdb.tsfile.read.common.block.TsBlock tsBlock)

Method Summary

Modifier and Type	Method	Description
long	calculateMaxPeekMemory()	We should also consider the memory used by its children operator, so the calculation logic may be like: long estimatedOfCurrentOperator = XXXXX; return max(estimatedOfCurrentOperator, child1.calculateMaxPeekMemory(), child2.calculateMaxPeekMemory(), ....)
long	calculateMaxReturnSize()
long	calculateRetainedSizeAfterCallingNext()
OperatorContext	getOperatorContext()
PlanNodeId	getSourceId()
boolean	hasNext()
boolean	isFinished()	Is this operator completely finished processing and no more output TsBlock will be produced.
org.apache.iotdb.tsfile.read.common.block.TsBlock	next()	Gets next tsBlock from this operator.

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.iotdb.db.mpp.execution.operator.Operator

close, isBlocked

Constructor Detail

LastCacheScanOperator

public LastCacheScanOperator(OperatorContext operatorContext,
                             PlanNodeId sourceId,
                             org.apache.iotdb.tsfile.read.common.block.TsBlock tsBlock)

Method Detail

getOperatorContext

public OperatorContext getOperatorContext()

Specified by:

getOperatorContext in interface Operator

next

public org.apache.iotdb.tsfile.read.common.block.TsBlock next()

Description copied from interface: Operator

Gets next tsBlock from this operator. If no data is currently available, return null.

Specified by:

next in interface Operator

hasNext

public boolean hasNext()

Specified by:

hasNext in interface Operator

Returns:

true if the operator has more data, otherwise false

isFinished

public boolean isFinished()

Description copied from interface: Operator

Is this operator completely finished processing and no more output TsBlock will be produced.

Specified by:

isFinished in interface Operator

calculateMaxPeekMemory

public long calculateMaxPeekMemory()

Description copied from interface: Operator

We should also consider the memory used by its children operator, so the calculation logic may be like: long estimatedOfCurrentOperator = XXXXX; return max(estimatedOfCurrentOperator, child1.calculateMaxPeekMemory(), child2.calculateMaxPeekMemory(), ....)

Each operator's MaxPeekMemory should also take retained size of each child operator into account.

Specified by:

calculateMaxPeekMemory in interface Operator

Returns:

estimated max memory footprint that the Operator Tree(rooted from this operator) will use while doing its own query processing

calculateMaxReturnSize

public long calculateMaxReturnSize()

Specified by:

calculateMaxReturnSize in interface Operator

Returns:

estimated max memory footprint for returned TsBlock when calling operator.next()

calculateRetainedSizeAfterCallingNext

public long calculateRetainedSizeAfterCallingNext()

Specified by:

calculateRetainedSizeAfterCallingNext in interface Operator

Returns:

each operator's retained size(including all its children's retained size) after calling its next() method

getSourceId

public PlanNodeId getSourceId()

Specified by:

getSourceId in interface SourceOperator