org.apache.calcite.adapter.enumerable

Enum NullPolicy

java.lang.Object

java.lang.Enum<NullPolicy>

org.apache.calcite.adapter.enumerable.NullPolicy

All Implemented Interfaces:

Serializable, Comparable<NullPolicy>

public enum NullPolicy
extends Enum<NullPolicy>

Describes when a function/operator will return null.

STRICT and ANY are similar. STRICT says f(a0, a1) will NEVER return null if a0 and a1 are not null. This means that we can check whether f returns null just by checking its arguments. Use STRICT in preference to ANY whenever possible.

Enum Constant Summary

Enum Constants

Enum Constant and Description
ALL Returns null if and only if all of the arguments are null; If all of the arguments are false return false otherwise true.
ANY If any of the arguments are null, return null.
ARG0 If the first argument is null, return null.
NONE
SEMI_STRICT Returns null if one of the arguments is null, and possibly other times.
STRICT Returns null if and only if one of the arguments are null.

Method Summary

Modifier and Type	Method and Description
static NullPolicy	valueOf(String name) Returns the enum constant of this type with the specified name.
static NullPolicy[]	values() Returns an array containing the constants of this enum type, in the order they are declared.

Methods inherited from class java.lang.Enum

clone, compareTo, equals, finalize, getDeclaringClass, hashCode, name, ordinal, toString, valueOf

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Enum Constant Detail

ALL

public static final NullPolicy ALL

Returns null if and only if all of the arguments are null; If all of the arguments are false return false otherwise true.

STRICT

public static final NullPolicy STRICT

Returns null if and only if one of the arguments are null.

SEMI_STRICT

public static final NullPolicy SEMI_STRICT

Returns null if one of the arguments is null, and possibly other times.

ANY

public static final NullPolicy ANY

If any of the arguments are null, return null.

ARG0

public static final NullPolicy ARG0

If the first argument is null, return null.

NONE

public static final NullPolicy NONE

Method Detail

values

public static NullPolicy[] values()

Returns an array containing the constants of this enum type, in the order they are declared. This method may be used to iterate over the constants as follows:

for (NullPolicy c : NullPolicy.values())
    System.out.println(c);

Returns:

an array containing the constants of this enum type, in the order they are declared

valueOf

public static NullPolicy valueOf(String name)

Returns the enum constant of this type with the specified name. The string must match exactly an identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.)

Parameters:

name - the name of the enum constant to be returned.

Returns:

the enum constant with the specified name

Throws:

IllegalArgumentException - if this enum type has no constant with the specified name

NullPointerException - if the argument is null