org.apache.hadoop.hbase

Class MetaCellComparator

java.lang.Object

org.apache.hadoop.hbase.CellComparatorImpl

org.apache.hadoop.hbase.MetaCellComparator

All Implemented Interfaces:

Comparator<Cell>, CellComparator

@InterfaceAudience.Private
 @InterfaceStability.Evolving
public class MetaCellComparator
extends CellComparatorImpl

A CellComparatorImpl for hbase:meta catalog table KeyValues.

Field Summary

Fields

Modifier and Type	Field and Description
static MetaCellComparator	META_COMPARATOR A MetaCellComparator for hbase:meta catalog table KeyValues.

Fields inherited from class org.apache.hadoop.hbase.CellComparatorImpl

COMPARATOR

Constructor Summary

Constructors

Constructor and Description
MetaCellComparator()

Method Summary

Modifier and Type	Method and Description
int	compare(Cell a, Cell b, boolean ignoreSequenceid) Compare cells.
private static int	compareRows(byte[] left, int loffset, int llength, byte[] right, int roffset, int rlength)
int	compareRows(ByteBuffer row, Cell cell)
int	compareRows(Cell left, byte[] right, int roffset, int rlength) Compares the row part of the cell with a simple plain byte[] like the stopRow in Scan.
int	compareRows(Cell left, Cell right) Compares the rows of the left and right cell.
Comparator	getSimpleComparator()

Methods inherited from class org.apache.hadoop.hbase.CellComparatorImpl

compare, compareColumns, compareFamilies, compareQualifiers, compareRows, compareTimestamps, compareTimestamps, compareWithoutRow, getCellComparator, getCellComparator

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.hadoop.hbase.CellComparator

getInstance

Methods inherited from interface java.util.Comparator

comparing, comparing, comparingDouble, comparingInt, comparingLong, equals, naturalOrder, nullsFirst, nullsLast, reversed, reverseOrder, thenComparing, thenComparing, thenComparing, thenComparingDouble, thenComparingInt, thenComparingLong

Field Detail

META_COMPARATOR

public static final MetaCellComparator META_COMPARATOR

A MetaCellComparator for hbase:meta catalog table KeyValues.

Constructor Detail

MetaCellComparator

public MetaCellComparator()

Method Detail

compareRows

public int compareRows(Cell left,
                       Cell right)

Description copied from class: CellComparatorImpl

Compares the rows of the left and right cell. For the hbase:meta case this method is overridden such that it can handle hbase:meta cells. The caller should ensure using the appropriate comparator for hbase:meta.

Specified by:

compareRows in interface CellComparator

Overrides:

compareRows in class CellComparatorImpl

Parameters:

left - the left hand side cell

right - the right hand side cell

Returns:

0 if both cells are equal, 1 if left cell is bigger than right, -1 otherwise

compareRows

public int compareRows(Cell left,
                       byte[] right,
                       int roffset,
                       int rlength)

Description copied from class: CellComparatorImpl

Compares the row part of the cell with a simple plain byte[] like the stopRow in Scan. This should be used with context where for hbase:meta cells the {META_COMPARATOR should be used

Specified by:

compareRows in interface CellComparator

Overrides:

compareRows in class CellComparatorImpl

Parameters:

left - the cell to be compared

right - the kv serialized byte[] to be compared with

roffset - the offset in the byte[]

rlength - the length in the byte[]

Returns:

0 if both cell and the byte[] are equal, 1 if the cell is bigger than byte[], -1 otherwise

compare

public int compare(Cell a,
                   Cell b,
                   boolean ignoreSequenceid)

Description copied from interface: CellComparator

Compare cells.

Specified by:

compare in interface CellComparator

Overrides:

compare in class CellComparatorImpl

ignoreSequenceid - True if we are to compare the key portion only and ignore the sequenceid. Set to false to compare key and consider sequenceid.

Returns:

0 if equal, -1 if a < b, and +1 if a > b.

compareRows

private static int compareRows(byte[] left,
                               int loffset,
                               int llength,
                               byte[] right,
                               int roffset,
                               int rlength)

compareRows

public int compareRows(ByteBuffer row,
                       Cell cell)

Parameters:

row - ByteBuffer that wraps a row; will read from current position and will reading all remaining; will not disturb the ByteBuffer internal state.

Returns:

greater than 0 if leftCell is bigger, less than 0 if rightCell is bigger, 0 if both cells are equal

getSimpleComparator

public Comparator getSimpleComparator()

Specified by:

getSimpleComparator in interface CellComparator

Overrides:

getSimpleComparator in class CellComparatorImpl

Returns:

A dumbed-down, fast comparator for hbase2 base-type, the ByteBufferKeyValue. Create an instance when you make a new memstore, when you know only BBKVs will be passed. Do not pollute with types other than BBKV if can be helped; the Comparator will slow.