Class SortBufferScan
- java.lang.Object
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- org.apache.derby.impl.store.access.sort.Scan
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- org.apache.derby.impl.store.access.sort.SortScan
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- org.apache.derby.impl.store.access.sort.SortBufferScan
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- All Implemented Interfaces:
ScanManager
,GenericScanController
,GroupFetchScanController
,RowCountable
,ScanController
,ScanInfo
public class SortBufferScan extends SortScan
A sort scan that just reads rows out of a sorter.
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Field Summary
Fields Modifier and Type Field Description protected SortBuffer
sortBuffer
The sorter we're returning rows from.-
Fields inherited from class org.apache.derby.impl.store.access.sort.SortScan
current, hold, sort, tran
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Fields inherited from interface org.apache.derby.iapi.store.access.ScanController
GE, GT, NA
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Constructor Summary
Constructors Constructor Description SortBufferScan(MergeSort sort, TransactionManager tran, SortBuffer sortBuffer, boolean hold)
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Method Summary
All Methods Instance Methods Concrete Methods Modifier and Type Method Description void
close()
Close the scan.boolean
closeForEndTransaction(boolean closeHeldScan)
Close the scan.boolean
next()
Move to the next position in the scan.-
Methods inherited from class org.apache.derby.impl.store.access.sort.SortScan
fetch, fetchNext, fetchWithoutQualify
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Methods inherited from class org.apache.derby.impl.store.access.sort.Scan
delete, didNotQualify, doesCurrentPositionQualify, fetchLocation, fetchNextGroup, fetchNextGroup, fetchSet, getAllScanInfo, getEstimatedRowCount, getScanInfo, isCurrentPositionDeleted, isHeldAfterCommit, isKeyed, isTableLocked, newRowLocationTemplate, positionAtRowLocation, reopenScan, reopenScanByRowLocation, replace, setEstimatedRowCount
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Field Detail
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sortBuffer
protected SortBuffer sortBuffer
The sorter we're returning rows from.
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Constructor Detail
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SortBufferScan
SortBufferScan(MergeSort sort, TransactionManager tran, SortBuffer sortBuffer, boolean hold)
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Method Detail
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next
public boolean next() throws StandardException
Move to the next position in the scan.- Returns:
- True if there is a next position in the scan, false if there isn't.
- Throws:
StandardException
- Standard exception policy.- See Also:
ScanController.next()
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closeForEndTransaction
public boolean closeForEndTransaction(boolean closeHeldScan)
Close the scan.- Parameters:
closeHeldScan
- If true, means to close scan even if it has been opened to be kept opened across commit. This is used to close these scans on abort.- Returns:
- boolean indicating that the close has resulted in a real close of the scan. A held scan will return false if called by closeForEndTransaction(false), otherwise it will return true. A non-held scan will always return true.
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close
public void close()
Close the scan.- Specified by:
close
in interfaceGenericScanController
- Overrides:
close
in classSortScan
- See Also:
GenericScanController.close()
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