org.apache.flink.table.runtime.functions.aggregate

类 BuiltInAggregateFunction<T,ACC>

java.lang.Object

org.apache.flink.table.functions.UserDefinedFunction

org.apache.flink.table.functions.ImperativeAggregateFunction<T,ACC>

org.apache.flink.table.functions.AggregateFunction<T,ACC>

org.apache.flink.table.runtime.functions.aggregate.BuiltInAggregateFunction<T,ACC>

所有已实现的接口:

Serializable, org.apache.flink.table.functions.FunctionDefinition

@Internal
public abstract class BuiltInAggregateFunction<T,ACC>
extends org.apache.flink.table.functions.AggregateFunction<T,ACC>

Base class for runtime implementation represented as AggregateFunction that is constructed from SpecializedFunction.specialize(SpecializedContext).

Subclasses must offer a constructor that takes SpecializedFunction.SpecializedContext if they are constructed from a BuiltInFunctionDefinition. Otherwise the BuiltInAggregateFunction() constructor might be more appropriate.

By default, all built-in functions work on internal data structures. However, this can be changed by overriding getArgumentDataTypes(), getAccumulatorDataType(), and getOutputDataType(). Or by overriding getTypeInference(DataTypeFactory) directly.

Since the accumulator type is runtime specific, it must be declared explicitly; otherwise it is derived from the output type.

另请参阅:

序列化表格

构造器概要

构造器

限定符	构造器和说明
protected	BuiltInAggregateFunction()
protected	BuiltInAggregateFunction(org.apache.flink.table.functions.BuiltInFunctionDefinition definition, org.apache.flink.table.functions.SpecializedFunction.SpecializedContext context)

方法概要

限定符和类型	方法和说明
org.apache.flink.table.types.DataType	getAccumulatorDataType()
List<org.apache.flink.table.types.DataType>	getArgumentDataTypes()
org.apache.flink.table.types.DataType	getOutputDataType()
Set<org.apache.flink.table.functions.FunctionRequirement>	getRequirements()
org.apache.flink.table.types.inference.TypeInference	getTypeInference(org.apache.flink.table.catalog.DataTypeFactory typeFactory)
boolean	isDeterministic()

从类继承的方法 org.apache.flink.table.functions.AggregateFunction

getKind, getValue

从类继承的方法 org.apache.flink.table.functions.ImperativeAggregateFunction

createAccumulator, getAccumulatorType, getResultType

从类继承的方法 org.apache.flink.table.functions.UserDefinedFunction

close, functionIdentifier, open, toString

从类继承的方法 java.lang.Object

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

构造器详细资料

BuiltInAggregateFunction

protected BuiltInAggregateFunction(org.apache.flink.table.functions.BuiltInFunctionDefinition definition,
                                   org.apache.flink.table.functions.SpecializedFunction.SpecializedContext context)

BuiltInAggregateFunction

protected BuiltInAggregateFunction()

方法详细资料

getArgumentDataTypes

public List<org.apache.flink.table.types.DataType> getArgumentDataTypes()

getAccumulatorDataType

public org.apache.flink.table.types.DataType getAccumulatorDataType()

getOutputDataType

public org.apache.flink.table.types.DataType getOutputDataType()

getTypeInference

public org.apache.flink.table.types.inference.TypeInference getTypeInference(org.apache.flink.table.catalog.DataTypeFactory typeFactory)

指定者:

getTypeInference 在接口中 org.apache.flink.table.functions.FunctionDefinition

覆盖:

getTypeInference 在类中 org.apache.flink.table.functions.AggregateFunction<T,ACC>

getRequirements

public Set<org.apache.flink.table.functions.FunctionRequirement> getRequirements()

isDeterministic

public boolean isDeterministic()