org.apache.hadoop.hbase.client.coprocessor

类 DoubleColumnInterpreter

java.lang.Object

org.apache.hadoop.hbase.coprocessor.ColumnInterpreter<Double,Double,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.EmptyMsg,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.DoubleMsg,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.DoubleMsg>

org.apache.hadoop.hbase.client.coprocessor.DoubleColumnInterpreter

@InterfaceAudience.LimitedPrivate(value="Coprocesssor")
@InterfaceStability.Evolving
public class DoubleColumnInterpreter
extends ColumnInterpreter<Double,Double,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.EmptyMsg,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.DoubleMsg,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.DoubleMsg>

a concrete column interpreter implementation. The cell value is a Double value and its promoted data type is also a Double 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 TestDoubleColumnInterpreter methods for its sample usage. Its methods handle null arguments gracefully.

构造器概要

构造器

构造器和说明
DoubleColumnInterpreter()

方法概要

方法

限定符和类型	方法和说明
Double	add(Double d1, Double d2)
Double	castToCellType(Double d) The response message comes as type S.
Double	castToReturnType(Double o) provides casting opportunity between the data types.
int	compare(Double d1, Double d2) 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.
double	divideForAvg(Double d1, Long l2) used for computing average of <S> data values.
Double	getCellValueFromProto(org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.DoubleMsg q) This method gets the PB message corresponding to the cell type
Double	getMaxValue() returns the maximum value for this type T
Double	getMinValue()
Double	getPromotedValueFromProto(org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.DoubleMsg r) This method gets the promoted type from the proto message
org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.DoubleMsg	getProtoForCellType(Double t) This method gets the PB message corresponding to the cell type
org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.DoubleMsg	getProtoForPromotedType(Double s) This method gets the PB message corresponding to the promoted type
org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.EmptyMsg	getRequestData() This method should return any additional data that is needed on the server side to construct the ColumnInterpreter.
Double	getValue(byte[] colFamily, byte[] colQualifier, Cell c)
Double	increment(Double o)
void	initialize(org.apache.hadoop.hbase.protobuf.generated.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).
Double	multiply(Double d1, Double d2)

从类继承的方法 java.lang.Object

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

构造器详细资料

DoubleColumnInterpreter

public DoubleColumnInterpreter()

方法详细资料

getValue

public Double getValue(byte[] colFamily,
              byte[] colQualifier,
              Cell c)
                throws IOException

指定者:

getValue 在类中 ColumnInterpreter<Double,Double,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.EmptyMsg,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.DoubleMsg,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.DoubleMsg>

返回:

value of type T

抛出:

IOException

add

public Double add(Double d1,
         Double d2)

指定者:

add 在类中 ColumnInterpreter<Double,Double,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.EmptyMsg,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.DoubleMsg,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.DoubleMsg>

返回:

sum or non null value among (if either of them is null); otherwise returns a null.

compare

public int compare(Double d1,
          Double d2)

从类复制的说明: 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.

指定者:

compare 在类中 ColumnInterpreter<Double,Double,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.EmptyMsg,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.DoubleMsg,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.DoubleMsg>

getMaxValue

public Double getMaxValue()

从类复制的说明: ColumnInterpreter

returns the maximum value for this type T

指定者:

getMaxValue 在类中 ColumnInterpreter<Double,Double,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.EmptyMsg,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.DoubleMsg,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.DoubleMsg>

返回:

max

increment

public Double increment(Double o)

指定者:

increment 在类中 ColumnInterpreter<Double,Double,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.EmptyMsg,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.DoubleMsg,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.DoubleMsg>

返回:

increment

multiply

public Double multiply(Double d1,
              Double d2)

指定者:

multiply 在类中 ColumnInterpreter<Double,Double,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.EmptyMsg,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.DoubleMsg,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.DoubleMsg>

返回:

multiplication

getMinValue

public Double getMinValue()

指定者:

getMinValue 在类中 ColumnInterpreter<Double,Double,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.EmptyMsg,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.DoubleMsg,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.DoubleMsg>

divideForAvg

public double divideForAvg(Double d1,
                  Long l2)

从类复制的说明: ColumnInterpreter

used for computing average of <S> data values. Not providing the divide method that takes two <S> values as it is not needed as of now.

指定者:

divideForAvg 在类中 ColumnInterpreter<Double,Double,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.EmptyMsg,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.DoubleMsg,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.DoubleMsg>

返回:

Average

castToReturnType

public Double castToReturnType(Double o)

从类复制的说明: ColumnInterpreter

provides casting opportunity between the data types.

指定者:

castToReturnType 在类中 ColumnInterpreter<Double,Double,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.EmptyMsg,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.DoubleMsg,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.DoubleMsg>

返回:

cast

castToCellType

public Double castToCellType(Double d)

从类复制的说明: 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)

指定者:

castToCellType 在类中 ColumnInterpreter<Double,Double,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.EmptyMsg,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.DoubleMsg,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.DoubleMsg>

返回:

cast

getRequestData

public org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.EmptyMsg getRequestData()

从类复制的说明: 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.

指定者:

getRequestData 在类中 ColumnInterpreter<Double,Double,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.EmptyMsg,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.DoubleMsg,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.DoubleMsg>

返回:

the PB message

initialize

public void initialize(org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.EmptyMsg msg)

从类复制的说明: ColumnInterpreter

This method should initialize any field(s) of the ColumnInterpreter with a parsing of the passed message bytes (used on the server side).

指定者:

initialize 在类中 ColumnInterpreter<Double,Double,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.EmptyMsg,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.DoubleMsg,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.DoubleMsg>

getProtoForCellType

public org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.DoubleMsg getProtoForCellType(Double t)

从类复制的说明: ColumnInterpreter

This method gets the PB message corresponding to the cell type

指定者:

getProtoForCellType 在类中 ColumnInterpreter<Double,Double,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.EmptyMsg,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.DoubleMsg,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.DoubleMsg>

返回:

the PB message for the cell-type instance

getProtoForPromotedType

public org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.DoubleMsg getProtoForPromotedType(Double s)

从类复制的说明: ColumnInterpreter

This method gets the PB message corresponding to the promoted type

指定者:

getProtoForPromotedType 在类中 ColumnInterpreter<Double,Double,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.EmptyMsg,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.DoubleMsg,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.DoubleMsg>

返回:

the PB message for the promoted-type instance

getPromotedValueFromProto

public Double getPromotedValueFromProto(org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.DoubleMsg r)

从类复制的说明: ColumnInterpreter

This method gets the promoted type from the proto message

指定者:

getPromotedValueFromProto 在类中 ColumnInterpreter<Double,Double,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.EmptyMsg,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.DoubleMsg,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.DoubleMsg>

返回:

the promoted-type instance from the PB message

getCellValueFromProto

public Double getCellValueFromProto(org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.DoubleMsg q)

从类复制的说明: ColumnInterpreter

This method gets the PB message corresponding to the cell type

指定者:

getCellValueFromProto 在类中 ColumnInterpreter<Double,Double,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.EmptyMsg,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.DoubleMsg,org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.DoubleMsg>

返回:

the cell-type instance from the PB message