NullKeyFieldException (Flink : Core 1.18.1-cp1 API)

java.lang.Object
- java.lang.Throwable
- - java.lang.Exception
  - - java.lang.RuntimeException
    - - org.apache.flink.types.NullKeyFieldException

All Implemented Interfaces:

Serializable
```
@Public
public class NullKeyFieldException
extends RuntimeException
```
An exception specifying that a required key field was not set in a record, i.e. was null.

See Also:

Serialized Form

Constructor Summary

Constructors
Constructor	Description
`NullKeyFieldException()`	Constructs an `NullKeyFieldException` with `null` as its error detail message.
`NullKeyFieldException(int fieldNumber)`	Constructs an `NullKeyFieldException` with a default message, referring to given field number as the null key field.
`NullKeyFieldException(String message)`	Constructs an `NullKeyFieldException` with the specified detail message.
`NullKeyFieldException(NullFieldException nfex)`	Constructs an `NullKeyFieldException` with a default message, referring to the field number given in the `NullFieldException`.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type Method Description

int getFieldNumber()
Gets the field number that was attempted to access.
- Methods inherited from class java.lang.Throwable
  addSuppressed, fillInStackTrace, getCause, getLocalizedMessage, getMessage, getStackTrace, getSuppressed, initCause, printStackTrace, printStackTrace, printStackTrace, setStackTrace, toString
- Methods inherited from class java.lang.Object
  clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

- Constructor Detail
  - NullKeyFieldException
```
public NullKeyFieldException()
```
    Constructs an NullKeyFieldException with null as its error detail message.
  - NullKeyFieldException
```
public NullKeyFieldException(NullFieldException nfex)
```
    Constructs an NullKeyFieldException with a default message, referring to the field number given in the NullFieldException.
    
    Parameters:
    
    nfex - The base exception.
  - NullKeyFieldException
```
public NullKeyFieldException(String message)
```
    Constructs an NullKeyFieldException with the specified detail message.
    
    Parameters:
    
    message - The detail message.
  - NullKeyFieldException
```
public NullKeyFieldException(int fieldNumber)
```
    Constructs an NullKeyFieldException with a default message, referring to given field number as the null key field.
    
    Parameters:
    
    fieldNumber - The index of the field that was null, bit expected to hold a key.
- Method Detail
  - getFieldNumber
```
public int getFieldNumber()
```
    Gets the field number that was attempted to access. If the number is not set, this method returns -1.
    
    Returns:
    
    The field number that was attempted to access, or -1, if not set.