LongColumnInterpreter (Apache HBase 1.1.7 API)

java.lang.Object
- org.apache.hadoop.hbase.coprocessor.ColumnInterpreter<Long,Long,HBaseProtos.EmptyMsg,HBaseProtos.LongMsg,HBaseProtos.LongMsg>
- - org.apache.hadoop.hbase.client.coprocessor.LongColumnInterpreter

```
@InterfaceAudience.Private
public class LongColumnInterpreter
extends ColumnInterpreter<Long,Long,HBaseProtos.EmptyMsg,HBaseProtos.LongMsg,HBaseProtos.LongMsg>
```
a concrete column interpreter implementation. The cell value is a Long value and its promoted data type is also a Long value. For computing aggregation function, this class is used to find the datatype of the cell value. Client is supposed to instantiate it and passed along as a parameter. See TestAggregateProtocol methods for its sample usage. Its methods handle null arguments gracefully.

Constructor Summary

Constructors
Constructor and Description

LongColumnInterpreter()

Constructors
Constructor and Description
`LongColumnInterpreter()`

Method Summary

Methods
Modifier and Type	Method and Description
`Long`	`add(Long l1, Long l2)`
`Long`	`castToCellType(Long l)` The response message comes as type S.
`Long`	`castToReturnType(Long o)` provides casting opportunity between the data types.
`int`	`compare(Long l1, Long l2)` This takes care if either of arguments are null.
`double`	`divideForAvg(Long l1, Long l2)` used for computing average of ~~data values.~~
`Long`	`getCellValueFromProto(HBaseProtos.LongMsg q)` This method gets the PB message corresponding to the cell type
`Long`	`getMaxValue()` returns the maximum value for this type T
`Long`	`getMinValue()`
`Long`	`getPromotedValueFromProto(HBaseProtos.LongMsg r)` This method gets the promoted type from the proto message
`HBaseProtos.LongMsg`	`getProtoForCellType(Long t)` This method gets the PB message corresponding to the cell type
`HBaseProtos.LongMsg`	`getProtoForPromotedType(Long s)` This method gets the PB message corresponding to the promoted type
`HBaseProtos.EmptyMsg`	`getRequestData()` This method should return any additional data that is needed on the server side to construct the ColumnInterpreter.
`Long`	`getValue(byte[] colFamily, byte[] colQualifier, Cell kv)`
`Long`	`increment(Long o)`
`void`	`initialize(HBaseProtos.EmptyMsg msg)` This method should initialize any field(s) of the ColumnInterpreter with a parsing of the passed message bytes (used on the server side).
`Long`	`multiply(Long l1, Long l2)`

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

- Constructor Detail
  - LongColumnInterpreter
```
public LongColumnInterpreter()
```
- Method Detail
  - getValue
```
public Long getValue(byte[] colFamily,
            byte[] colQualifier,
            Cell kv)
              throws IOException
```
    Specified by:
    
    getValue in class ColumnInterpreter<Long,Long,HBaseProtos.EmptyMsg,HBaseProtos.LongMsg,HBaseProtos.LongMsg>
    
    Returns:
    value of type T
    
    Throws:
    
    IOException
  - add
```
public Long add(Long l1,
       Long l2)
```
    Specified by:
    
    add in class ColumnInterpreter<Long,Long,HBaseProtos.EmptyMsg,HBaseProtos.LongMsg,HBaseProtos.LongMsg>
    
    Returns:
    sum or non null value among (if either of them is null); otherwise returns a null.
  - compare
```
public int compare(Long l1,
          Long l2)
```
    Description copied from class: ColumnInterpreter
    This takes care if either of arguments are null. returns 0 if they are equal or both are null;
    - >0 if l1 > l2 or l1 is not null and l2 is null.
    - < 0 if l1 < l2 or l1 is null and l2 is not null.
    Specified by:
    
    compare in class ColumnInterpreter<Long,Long,HBaseProtos.EmptyMsg,HBaseProtos.LongMsg,HBaseProtos.LongMsg>
  - getMaxValue
```
public Long getMaxValue()
```
    Description copied from class: ColumnInterpreter
    
    returns the maximum value for this type T
    
    Specified by:
    
    getMaxValue in class ColumnInterpreter<Long,Long,HBaseProtos.EmptyMsg,HBaseProtos.LongMsg,HBaseProtos.LongMsg>
    
    Returns:
    max
  - increment
```
public Long increment(Long o)
```
    Specified by:
    
    increment in class ColumnInterpreter<Long,Long,HBaseProtos.EmptyMsg,HBaseProtos.LongMsg,HBaseProtos.LongMsg>
    
    Returns:
    increment
  - multiply
```
public Long multiply(Long l1,
            Long l2)
```
    Specified by:
    
    multiply in class ColumnInterpreter<Long,Long,HBaseProtos.EmptyMsg,HBaseProtos.LongMsg,HBaseProtos.LongMsg>
    
    Returns:
    multiplication
  - getMinValue
```
public Long getMinValue()
```
    Specified by:
    
    getMinValue in class ColumnInterpreter<Long,Long,HBaseProtos.EmptyMsg,HBaseProtos.LongMsg,HBaseProtos.LongMsg>
  - divideForAvg
```
public double divideForAvg(Long l1,
                  Long l2)
```
    Description copied from class: ColumnInterpreter
    
    used for computing average of ~~data values. Not providing the divide method that takes two ~~values as it is not needed as of now.~~~~
    
    Specified by:
    
    divideForAvg in class ColumnInterpreter<Long,Long,HBaseProtos.EmptyMsg,HBaseProtos.LongMsg,HBaseProtos.LongMsg>
    
    Returns:
    Average
  castToReturnType
  
  public Long castToReturnType(Long o)
  
  Description copied from class: ColumnInterpreter
  
  provides casting opportunity between the data types.
  
  Specified by:
  
  castToReturnType in class ColumnInterpreter<Long,Long,HBaseProtos.EmptyMsg,HBaseProtos.LongMsg,HBaseProtos.LongMsg>
  
  Returns:
  cast
  
  castToCellType
  
  public Long castToCellType(Long l)
  
  Description copied from class: ColumnInterpreter
  
  The response message comes as type S. This will convert/cast it to T. In some sense, performs the opposite of ColumnInterpreter.castToReturnType(Object)
  
  Specified by:
  
  castToCellType in class ColumnInterpreter<Long,Long,HBaseProtos.EmptyMsg,HBaseProtos.LongMsg,HBaseProtos.LongMsg>
  
  Returns:
  cast
  
  getRequestData
  
  public HBaseProtos.EmptyMsg getRequestData()
  
  Description copied from class: ColumnInterpreter
  
  This method should return any additional data that is needed on the server side to construct the ColumnInterpreter. The server will pass this to the ColumnInterpreter.initialize(P) method. If there is no ColumnInterpreter specific data (for e.g., LongColumnInterpreter) then null should be returned.
  
  Specified by:
  
  getRequestData in class ColumnInterpreter<Long,Long,HBaseProtos.EmptyMsg,HBaseProtos.LongMsg,HBaseProtos.LongMsg>
  
  Returns:
  the PB message
  
  initialize
  
  public void initialize(HBaseProtos.EmptyMsg msg)
  
  Description copied from class: ColumnInterpreter
  
  This method should initialize any field(s) of the ColumnInterpreter with a parsing of the passed message bytes (used on the server side).
  
  Specified by:
  
  initialize in class ColumnInterpreter<Long,Long,HBaseProtos.EmptyMsg,HBaseProtos.LongMsg,HBaseProtos.LongMsg>
  
  getProtoForCellType
  
  public HBaseProtos.LongMsg getProtoForCellType(Long t)
  
  Description copied from class: ColumnInterpreter
  
  This method gets the PB message corresponding to the cell type
  
  Specified by:
  
  getProtoForCellType in class ColumnInterpreter<Long,Long,HBaseProtos.EmptyMsg,HBaseProtos.LongMsg,HBaseProtos.LongMsg>
  
  Returns:
  the PB message for the cell-type instance
  
  getProtoForPromotedType
  
  public HBaseProtos.LongMsg getProtoForPromotedType(Long s)
  
  Description copied from class: ColumnInterpreter
  
  This method gets the PB message corresponding to the promoted type
  
  Specified by:
  
  getProtoForPromotedType in class ColumnInterpreter<Long,Long,HBaseProtos.EmptyMsg,HBaseProtos.LongMsg,HBaseProtos.LongMsg>
  
  Returns:
  the PB message for the promoted-type instance
  
  getPromotedValueFromProto
  
  public Long getPromotedValueFromProto(HBaseProtos.LongMsg r)
  
  Description copied from class: ColumnInterpreter
  
  This method gets the promoted type from the proto message
  
  Specified by:
  
  getPromotedValueFromProto in class ColumnInterpreter<Long,Long,HBaseProtos.EmptyMsg,HBaseProtos.LongMsg,HBaseProtos.LongMsg>
  
  Returns:
  the promoted-type instance from the PB message
  
  getCellValueFromProto
  
  public Long getCellValueFromProto(HBaseProtos.LongMsg q)
  
  Description copied from class: ColumnInterpreter
  
  This method gets the PB message corresponding to the cell type
  
  Specified by:
  
  getCellValueFromProto in class ColumnInterpreter<Long,Long,HBaseProtos.EmptyMsg,HBaseProtos.LongMsg,HBaseProtos.LongMsg>
  
  Returns:
  the cell-type instance from the PB message

Class LongColumnInterpreter

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

LongColumnInterpreter

Method Detail

getValue

add

compare

getMaxValue

increment

multiply

getMinValue

divideForAvg

castToReturnType

castToCellType

getRequestData

initialize

getProtoForCellType

getProtoForPromotedType

getPromotedValueFromProto

getCellValueFromProto