org.apache.flink.table.functions

类 UserDefinedFunction

java.lang.Object

org.apache.flink.table.functions.UserDefinedFunction

所有已实现的接口:

Serializable, FunctionDefinition

直接已知子类:

AsyncTableFunction, ScalarFunction, TableFunction, UserDefinedAggregateFunction

@PublicEvolving
public abstract class UserDefinedFunction
extends Object
implements FunctionDefinition, Serializable

Base class for all user-defined functions.

User-defined functions combine the logical definition of a function for validation and planning and contain a corresponding runtime implementation.

另请参阅:

ScalarFunction, TableFunction, AsyncTableFunction, AggregateFunction, TableAggregateFunction, 序列化表格

构造器概要

构造器

构造器和说明
UserDefinedFunction()

方法概要

限定符和类型	方法和说明
void	close() Tear-down method for user-defined function.
String	functionIdentifier() Returns a unique, serialized representation for this function.
void	open(FunctionContext context) Setup method for user-defined function.
String	toString() Returns the name of the UDF that is used for plan explanation and logging.

从类继承的方法 java.lang.Object

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

从接口继承的方法 org.apache.flink.table.functions.FunctionDefinition

getKind, getRequirements, isDeterministic

构造器详细资料

UserDefinedFunction

public UserDefinedFunction()

方法详细资料

functionIdentifier

public final String functionIdentifier()

Returns a unique, serialized representation for this function.

open

public void open(FunctionContext context)
          throws Exception

Setup method for user-defined function. It can be used for initialization work. By default, this method does nothing.

抛出:

Exception

close

public void close()
           throws Exception

Tear-down method for user-defined function. It can be used for clean up work. By default, this method does nothing.

抛出:

Exception

toString

public String toString()

Returns the name of the UDF that is used for plan explanation and logging.

覆盖:

toString 在类中 Object