PrefixTreeArrayScanner (Apache HBase 1.4.11 API)

java.lang.Object
- org.apache.hadoop.hbase.codec.prefixtree.decode.PrefixTreeCell
- - org.apache.hadoop.hbase.codec.prefixtree.decode.PrefixTreeArrayScanner

All Implemented Interfaces:

Comparable<Cell>, Cell, CellScanner, SettableSequenceId

Direct Known Subclasses:

PrefixTreeArrayReversibleScanner
```
@InterfaceAudience.Private
public class PrefixTreeArrayScanner
extends PrefixTreeCell
implements CellScanner
```
Extends PtCell and manipulates its protected fields. Could alternatively contain a PtCell and call get/set methods. This is an "Array" scanner to distinguish from a future "ByteBuffer" scanner. This implementation requires that the bytes be in a normal java byte[] for performance. The alternative ByteBuffer implementation would allow for accessing data in an off-heap ByteBuffer without copying the whole buffer on-heap.

Field Summary

Fields
Modifier and Type	Field and Description
`protected boolean`	`afterLast`
`protected boolean`	`beforeFirst`
`protected PrefixTreeBlockMeta`	`blockMeta` fields
`protected int`	`currentCellIndex`
`protected RowNodeReader`	`currentRowNode`
`protected ColumnReader`	`familyReader`
`protected MvccVersionDecoder`	`mvccVersionDecoder`
`protected boolean`	`nubCellsRemain`
`protected ColumnReader`	`qualifierReader`
`protected RowNodeReader[]`	`rowNodes`
`protected int`	`rowNodeStackIndex`
`protected ColumnReader`	`tagsReader`
`protected TimestampDecoder`	`timestampDecoder`

Fields inherited from class org.apache.hadoop.hbase.codec.prefixtree.decode.PrefixTreeCell
absoluteValueOffset, block, DEFAULT_TYPE, familyBuffer, familyLength, familyOffset, includeMvccVersion, mvccVersion, qualifierBuffer, qualifierLength, qualifierOffset, rowBuffer, rowLength, tagsBuffer, tagsLength, tagsOffset, timestamp, type, TYPES, valueLength

Constructor Summary

Constructors
Constructor and Description
`PrefixTreeArrayScanner(PrefixTreeBlockMeta blockMeta, int rowTreeDepth, int rowBufferLength, int qualifierBufferLength, int tagsBufferLength)` construct

Method Summary

Methods
Modifier and Type	Method and Description
`boolean`	`advance()` Advance the scanner 1 cell.
`protected void`	`appendCurrentTokenToRowBuffer()` helper methods
`protected void`	`appendToRowBuffer(byte b)`
`boolean`	`areBuffersBigEnough()` Call when first accessing a block.
`Cell`	`current()` CellScanner
`protected void`	`discardCurrentRowNode(boolean forwards)`
`boolean`	`equals(Object obj)` Object methods
`protected void`	`followCurrentFan()`
`protected void`	`followFan(int fanIndex)`
`protected void`	`followFirstFan()`
`protected void`	`followLastFan()`
`protected void`	`followNextFan()`
`protected void`	`followPreviousFan()`
`PrefixTreeBlockMeta`	`getBlockMeta()`
`int`	`getMaxRowTreeStackNodes()`
`int`	`getQualifierBufferLength()`
`int`	`getRowBufferLength()`
`int`	`getTagBufferLength()`
`byte[]`	`getTreeBytes()` getters
`int`	`hashCode()`
`protected boolean`	`hasOccurrences()`
`protected void`	`initFirstNode()`
`void`	`initOnBlock(PrefixTreeBlockMeta blockMeta, byte[] block, boolean includeMvccVersion)`
`boolean`	`isAfterLast()`
`boolean`	`isBeforeFirst()`
`protected boolean`	`isBranch()`
`protected boolean`	`isFirstCellInRow()`
`protected boolean`	`isLastCellInRow()`
`protected boolean`	`isLeaf()`
`protected boolean`	`isNub()`
`protected boolean`	`isOutOfBounds()`
`protected void`	`markAfterLast()`
`protected void`	`markBeforeFirst()`
`boolean`	`nextRow()`
`protected boolean`	`nextRowInternal()` This method is safe to call when the scanner is not on a fully valid row node, as in the case of a row token miss in the Searcher
`protected void`	`popFromRowBuffer(RowNodeReader rowNodeBeingPopped)`
`protected void`	`populateFamily()`
`protected void`	`populateFirstNonRowFields()`
`protected void`	`populateLastNonRowFields()`
`protected void`	`populateMvccVersion()`
`protected void`	`populateNonRowFields(int cellIndex)`
`protected int`	`populateNonRowFieldsAndCompareTo(int cellNum, Cell key)` fill in family/qualifier/ts/type/value
`protected void`	`populatePreviousNonRowFields()`
`protected void`	`populateQualifier()`
`protected void`	`populateTag()`
`protected void`	`populateTimestamp()`
`protected void`	`populateType()`
`protected void`	`populateValueOffsets()`
`boolean`	`positionAtFirstCell()` advance
`protected void`	`reInitFirstNode()` secondary traversal methods
`void`	`releaseBlockReference()` Call this before putting the scanner back into a pool so it doesn't hold the last used block in memory.
`void`	`resetToBeforeFirstEntry()`
`String`	`toString()` Override PrefixTreeCell.toString() with a check to see if the current cell is valid.

Methods inherited from class org.apache.hadoop.hbase.codec.prefixtree.decode.PrefixTreeCell
compareTo, getFamily, getFamilyArray, getFamilyLength, getFamilyOffset, getKeyValueString, getMvccVersion, getQualifier, getQualifierArray, getQualifierLength, getQualifierOffset, getRow, getRowArray, getRowLength, getRowOffset, getSequenceId, getTagsArray, getTagsLength, getTagsOffset, getTimestamp, getTypeByte, getValue, getValueArray, getValueLength, getValueOffset, setSequenceId

Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

blockMeta

protected PrefixTreeBlockMeta blockMeta

fields

beforeFirst
```
protected boolean beforeFirst
```

afterLast
```
protected boolean afterLast
```

rowNodes
```
protected RowNodeReader[] rowNodes
```

rowNodeStackIndex
```
protected int rowNodeStackIndex
```

currentRowNode
```
protected RowNodeReader currentRowNode
```

familyReader
```
protected ColumnReader familyReader
```

qualifierReader
```
protected ColumnReader qualifierReader
```

tagsReader
```
protected ColumnReader tagsReader
```

timestampDecoder

protected TimestampDecoder timestampDecoder

mvccVersionDecoder

protected MvccVersionDecoder mvccVersionDecoder

nubCellsRemain
```
protected boolean nubCellsRemain
```

currentCellIndex
```
protected int currentCellIndex
```

Constructor Detail

PrefixTreeArrayScanner

public PrefixTreeArrayScanner(PrefixTreeBlockMeta blockMeta,
                      int rowTreeDepth,
                      int rowBufferLength,
                      int qualifierBufferLength,
                      int tagsBufferLength)

construct

Method Detail

areBuffersBigEnough
```
public boolean areBuffersBigEnough()
```
Call when first accessing a block.

Returns:
entirely new scanner if false

initOnBlock

public void initOnBlock(PrefixTreeBlockMeta blockMeta,
               byte[] block,
               boolean includeMvccVersion)

resetToBeforeFirstEntry
```
public void resetToBeforeFirstEntry()
```

releaseBlockReference
```
public void releaseBlockReference()
```
Call this before putting the scanner back into a pool so it doesn't hold the last used block in memory.

current
```
public Cell current()
```
CellScanner

Specified by:

current in interface CellScanner

Returns:
the current Cell which may be mutable

equals
```
public boolean equals(Object obj)
```
Object methods

Overrides:

equals in class PrefixTreeCell

hashCode
```
public int hashCode()
```
Overrides:

hashCode in class PrefixTreeCell

toString
```
public String toString()
```
Override PrefixTreeCell.toString() with a check to see if the current cell is valid.

Overrides:

toString in class PrefixTreeCell

positionAtFirstCell
```
public boolean positionAtFirstCell()
```
advance

advance
```
public boolean advance()
```
Description copied from interface: CellScanner

Advance the scanner 1 cell.

Specified by:

advance in interface CellScanner

Returns:
true if the next cell is found and CellScanner.current() will return a valid Cell

nextRow
```
public boolean nextRow()
```

nextRowInternal
```
protected boolean nextRowInternal()
```
This method is safe to call when the scanner is not on a fully valid row node, as in the case of a row token miss in the Searcher

Returns:
true if we are positioned on a valid row, false if past end of block

reInitFirstNode
```
protected void reInitFirstNode()
```
secondary traversal methods

initFirstNode
```
protected void initFirstNode()
```

followFirstFan
```
protected void followFirstFan()
```

followPreviousFan
```
protected void followPreviousFan()
```

followCurrentFan
```
protected void followCurrentFan()
```

followNextFan
```
protected void followNextFan()
```

followLastFan
```
protected void followLastFan()
```

followFan

protected void followFan(int fanIndex)

discardCurrentRowNode
```
protected void discardCurrentRowNode(boolean forwards)
```
Parameters:
forwards - which marker to set if we overflow

markBeforeFirst
```
protected void markBeforeFirst()
```

markAfterLast
```
protected void markAfterLast()
```

appendCurrentTokenToRowBuffer

protected void appendCurrentTokenToRowBuffer()

helper methods

appendToRowBuffer

protected void appendToRowBuffer(byte b)

popFromRowBuffer

protected void popFromRowBuffer(RowNodeReader rowNodeBeingPopped)

hasOccurrences
```
protected boolean hasOccurrences()
```

isBranch
```
protected boolean isBranch()
```

isNub
```
protected boolean isNub()
```

isLeaf
```
protected boolean isLeaf()
```

isBeforeFirst
```
public boolean isBeforeFirst()
```

isAfterLast
```
public boolean isAfterLast()
```

isOutOfBounds
```
protected boolean isOutOfBounds()
```

isFirstCellInRow
```
protected boolean isFirstCellInRow()
```

isLastCellInRow
```
protected boolean isLastCellInRow()
```

populateNonRowFieldsAndCompareTo

protected int populateNonRowFieldsAndCompareTo(int cellNum,
                                   Cell key)

fill in family/qualifier/ts/type/value

populateFirstNonRowFields

protected void populateFirstNonRowFields()

populatePreviousNonRowFields

protected void populatePreviousNonRowFields()

populateLastNonRowFields

protected void populateLastNonRowFields()

populateNonRowFields

protected void populateNonRowFields(int cellIndex)

populateFamily
```
protected void populateFamily()
```

populateQualifier
```
protected void populateQualifier()
```

populateTag
```
protected void populateTag()
```

populateTimestamp
```
protected void populateTimestamp()
```

populateMvccVersion
```
protected void populateMvccVersion()
```

populateType
```
protected void populateType()
```

populateValueOffsets
```
protected void populateValueOffsets()
```

getTreeBytes
```
public byte[] getTreeBytes()
```
getters

getBlockMeta

public PrefixTreeBlockMeta getBlockMeta()

getMaxRowTreeStackNodes
```
public int getMaxRowTreeStackNodes()
```

getRowBufferLength
```
public int getRowBufferLength()
```

getQualifierBufferLength
```
public int getQualifierBufferLength()
```

getTagBufferLength
```
public int getTagBufferLength()
```

Class PrefixTreeArrayScanner

Field Summary

Fields inherited from class org.apache.hadoop.hbase.codec.prefixtree.decode.PrefixTreeCell

Constructor Summary

Method Summary

Methods inherited from class org.apache.hadoop.hbase.codec.prefixtree.decode.PrefixTreeCell

Methods inherited from class java.lang.Object

Field Detail

blockMeta

beforeFirst

afterLast

rowNodes

rowNodeStackIndex

currentRowNode

familyReader

qualifierReader

tagsReader

timestampDecoder

mvccVersionDecoder

nubCellsRemain

currentCellIndex

Constructor Detail

PrefixTreeArrayScanner

Method Detail

areBuffersBigEnough

initOnBlock

resetToBeforeFirstEntry

releaseBlockReference

current

equals

hashCode

toString

positionAtFirstCell

advance

nextRow

nextRowInternal

reInitFirstNode

initFirstNode

followFirstFan

followPreviousFan

followCurrentFan

followNextFan

followLastFan

followFan

discardCurrentRowNode

markBeforeFirst

markAfterLast

appendCurrentTokenToRowBuffer

appendToRowBuffer

popFromRowBuffer

hasOccurrences

isBranch

isNub

isLeaf

isBeforeFirst

isAfterLast

isOutOfBounds

isFirstCellInRow

isLastCellInRow

populateNonRowFieldsAndCompareTo

populateFirstNonRowFields

populatePreviousNonRowFields

populateLastNonRowFields

populateNonRowFields

populateFamily

populateQualifier

populateTag

populateTimestamp

populateMvccVersion

populateType

populateValueOffsets

getTreeBytes

getBlockMeta

getMaxRowTreeStackNodes

getRowBufferLength

getQualifierBufferLength

getTagBufferLength