RegionSplitter.UniformSplit (Apache HBase 1.4.11 API)

java.lang.Object
- org.apache.hadoop.hbase.util.RegionSplitter.UniformSplit

All Implemented Interfaces:

RegionSplitter.SplitAlgorithm

Enclosing class:

RegionSplitter
```
public static class RegionSplitter.UniformSplit
extends Object
implements RegionSplitter.SplitAlgorithm
```
A SplitAlgorithm that divides the space of possible keys evenly. Useful when the keys are approximately uniform random bytes (e.g. hashes). Rows are raw byte values in the range 00 => FF and are right-padded with zeros to keep the same memcmp() order. This is the natural algorithm to use for a byte[] environment and saves space, but is not necessarily the easiest for readability.

Constructor Summary

Constructors
Constructor and Description

RegionSplitter.UniformSplit()

Constructors
Constructor and Description
`RegionSplitter.UniformSplit()`

Method Summary

Methods
Modifier and Type	Method and Description
`byte[]`	`firstRow()` In HBase, the first row is represented by an empty byte array.
`byte[]`	`lastRow()` In HBase, the last row is represented by an empty byte array.
`String`	`rowToStr(byte[] row)`
`String`	`separator()`
`void`	`setFirstRow(byte[] userInput)` Set the first row
`void`	`setFirstRow(String userInput)` In HBase, the last row is represented by an empty byte array.
`void`	`setLastRow(byte[] userInput)` Set the last row
`void`	`setLastRow(String userInput)` In HBase, the last row is represented by an empty byte array.
`byte[]`	`split(byte[] start, byte[] end)` Split a pre-existing region into 2 regions.
`byte[][]`	`split(byte[] start, byte[] end, int numSplits, boolean inclusive)` Some MapReduce jobs may want to run multiple mappers per region, this is intended for such usecase.
`byte[][]`	`split(int numRegions)` Split an entire table.
`byte[]`	`strToRow(String input)`
`String`	`toString()`

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

- Constructor Detail
  - RegionSplitter.UniformSplit
```
public RegionSplitter.UniformSplit()
```
- Method Detail
  - split
```
public byte[] split(byte[] start,
           byte[] end)
```
    Description copied from interface: RegionSplitter.SplitAlgorithm
    
    Split a pre-existing region into 2 regions.
    
    Specified by:
    
    split in interface RegionSplitter.SplitAlgorithm
    
    Parameters:
    start - first row (inclusive)
    end - last row (exclusive)
    
    Returns:
    the split row to use
  - split
```
public byte[][] split(int numRegions)
```
    Description copied from interface: RegionSplitter.SplitAlgorithm
    
    Split an entire table.
    
    Specified by:
    
    split in interface RegionSplitter.SplitAlgorithm
    
    Parameters:
    numRegions - number of regions to split the table into
    
    Returns:
    array of split keys for the initial regions of the table. The length of the returned array should be numRegions-1.
  - split
```
public byte[][] split(byte[] start,
             byte[] end,
             int numSplits,
             boolean inclusive)
```
    Description copied from interface: RegionSplitter.SplitAlgorithm
    
    Some MapReduce jobs may want to run multiple mappers per region, this is intended for such usecase.
    
    Specified by:
    
    split in interface RegionSplitter.SplitAlgorithm
    
    Parameters:
    start - first row (inclusive)
    end - last row (exclusive)
    numSplits - number of splits to generate
    inclusive - whether start and end are returned as split points
  - firstRow
```
public byte[] firstRow()
```
    Description copied from interface: RegionSplitter.SplitAlgorithm
    
    In HBase, the first row is represented by an empty byte array. This might cause problems with your split algorithm or row printing. All your APIs will be passed firstRow() instead of empty array.
    
    Specified by:
    
    firstRow in interface RegionSplitter.SplitAlgorithm
    
    Returns:
    your representation of your first row
  - lastRow
```
public byte[] lastRow()
```
    Description copied from interface: RegionSplitter.SplitAlgorithm
    
    In HBase, the last row is represented by an empty byte array. This might cause problems with your split algorithm or row printing. All your APIs will be passed firstRow() instead of empty array.
    
    Specified by:
    
    lastRow in interface RegionSplitter.SplitAlgorithm
    
    Returns:
    your representation of your last row
  - setFirstRow
```
public void setFirstRow(String userInput)
```
    Description copied from interface: RegionSplitter.SplitAlgorithm
    
    In HBase, the last row is represented by an empty byte array. Set this value to help the split code understand how to evenly divide the first region.
    
    Specified by:
    
    setFirstRow in interface RegionSplitter.SplitAlgorithm
    
    Parameters:
    userInput - raw user input (may throw RuntimeException on parse failure)
  - setLastRow
```
public void setLastRow(String userInput)
```
    Description copied from interface: RegionSplitter.SplitAlgorithm
    
    In HBase, the last row is represented by an empty byte array. Set this value to help the split code understand how to evenly divide the last region. Note that this last row is inclusive for all rows sharing the same prefix.
    
    Specified by:
    
    setLastRow in interface RegionSplitter.SplitAlgorithm
    
    Parameters:
    userInput - raw user input (may throw RuntimeException on parse failure)
  - setFirstRow
```
public void setFirstRow(byte[] userInput)
```
    Description copied from interface: RegionSplitter.SplitAlgorithm
    
    Set the first row
    
    Specified by:
    
    setFirstRow in interface RegionSplitter.SplitAlgorithm
    
    Parameters:
    userInput - byte array of the row key.
  - setLastRow
```
public void setLastRow(byte[] userInput)
```
    Description copied from interface: RegionSplitter.SplitAlgorithm
    
    Set the last row
    
    Specified by:
    
    setLastRow in interface RegionSplitter.SplitAlgorithm
    
    Parameters:
    userInput - byte array of the row key.
  - strToRow
```
public byte[] strToRow(String input)
```
    Specified by:
    
    strToRow in interface RegionSplitter.SplitAlgorithm
    
    Parameters:
    input - user or file input for row
    
    Returns:
    byte array representation of this row for HBase
  - rowToStr
```
public String rowToStr(byte[] row)
```
    Specified by:
    
    rowToStr in interface RegionSplitter.SplitAlgorithm
    
    Parameters:
    row - byte array representing a row in HBase
    
    Returns:
    String to use for debug & file printing
  - separator
```
public String separator()
```
    Specified by:
    
    separator in interface RegionSplitter.SplitAlgorithm
    
    Returns:
    the separator character to use when storing / printing the row
  - toString
```
public String toString()
```
    Overrides:
    
    toString in class Object

Class RegionSplitter.UniformSplit

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

RegionSplitter.UniformSplit

Method Detail

split

split

split

firstRow

lastRow

setFirstRow

setLastRow

setFirstRow

setLastRow

strToRow

rowToStr

separator

toString