UserDefinedFunction (flink-cdc-parent 3.8-SNAPSHOT API)

All Known Implementing Classes:

AddOneFunctionClass, BinaryTypeReturningClass, CharTypeReturningClass, ConfigurableFunctionClass, DecimalTypeNonNullReturningClass, DecimalTypeReturningClass, FormatFunctionClass, LifecycleFunctionClass, LocalZonedTimestampTypeReturningClass, OpenAIChatModel, OpenAIEmbeddingModel, PythonUdf, SkewedThrottlerFunctionClass, ThrottlerFunctionClass, TimestampTypeReturningClass, TypeHintFunctionClass, TypeOfFunctionClass, VarBinaryTypeReturningClass, VarCharTypeReturningClass
```
@PublicEvolving
public interface UserDefinedFunction
```
Base interface for creating a UDF in transform projection and filtering expressions. You should define at least one eval method.
When transform.async-execution.enabled is enabled, the same UDF instance may be invoked concurrently. Implementations used in asynchronous transforms must therefore be thread-safe.

Method Summary

All Methods Instance Methods Default Methods Deprecated Methods
Modifier and Type	Method	Description
`default void`	`close()`	This will be invoked before a UDF got destroyed.
`default DataType`	`getReturnType()`	Deprecated. Use `getReturnType(UserDefinedFunctionContext)` instead.
`default DataType`	`getReturnType(UserDefinedFunctionContext context)`	Returns the return type of this UDF, given the per-UDF YAML options.
`default void`	`open()`	Deprecated. Use `open(UserDefinedFunctionContext)` instead.
`default void`	`open(UserDefinedFunctionContext context)`	This will be invoked every time when a UDF got created.

- Method Detail
  - getReturnType
```
@Deprecated
default DataType getReturnType()
```
    Deprecated.
    Use getReturnType(UserDefinedFunctionContext) instead.
    
    Returns the return type of this UDF when it cannot be derived from per-UDF options.
  - getReturnType
```
default DataType getReturnType(UserDefinedFunctionContext context)
```
    Returns the return type of this UDF, given the per-UDF YAML options.
  - open
```
@Deprecated
default void open()
           throws Exception
```
    Deprecated.
    Use open(UserDefinedFunctionContext) instead.
    
    This will be invoked every time when a UDF got created.
    
    Throws:
    
    Exception
  - open
```
default void open(UserDefinedFunctionContext context)
           throws Exception
```
    This will be invoked every time when a UDF got created.
    
    Throws:
    
    Exception
  - close
```
default void close()
            throws Exception
```
    This will be invoked before a UDF got destroyed.
    
    Throws:
    
    Exception