org.apache.calcite.adapter.enumerable

Enum RexImpTable.NullAs

java.lang.Object

java.lang.Enum<RexImpTable.NullAs>

org.apache.calcite.adapter.enumerable.RexImpTable.NullAs

All Implemented Interfaces:

Serializable, Comparable<RexImpTable.NullAs>

Enclosing class:

RexImpTable

public static enum RexImpTable.NullAs
extends Enum<RexImpTable.NullAs>

Strategy what an operator should return if one of its arguments is null.

Enum Constant Summary

Enum Constants

Enum Constant and Description
FALSE If one of the arguments is null, the function returns false.
IS_NOT_NULL Return true if result is not null, false if result is null.
IS_NULL Return false if result is not null, true if result is null.
NOT_POSSIBLE It is not possible for any of the arguments to be null.
NULL The most common policy among the SQL built-in operators.
TRUE If one of the arguments is null, the function returns true.

Method Summary

Methods

Modifier and Type	Method and Description
Expression	handle(Expression x) Adapts an expression with "normal" result to one that adheres to this particular policy.
static RexImpTable.NullAs	of(boolean nullable)
static RexImpTable.NullAs	valueOf(String name) Returns the enum constant of this type with the specified name.
static RexImpTable.NullAs[]	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

NULL

public static final RexImpTable.NullAs NULL

The most common policy among the SQL built-in operators. If one of the arguments is null, returns null.

FALSE

public static final RexImpTable.NullAs FALSE

If one of the arguments is null, the function returns false. Example: IS NOT NULL.

TRUE

public static final RexImpTable.NullAs TRUE

If one of the arguments is null, the function returns true. Example: IS NULL.

NOT_POSSIBLE

public static final RexImpTable.NullAs NOT_POSSIBLE

It is not possible for any of the arguments to be null. If the argument type is nullable, the enclosing code will already have performed a not-null check. This may allow the operator implementor to generate a more efficient implementation, for example, by avoiding boxing or unboxing.

IS_NULL

public static final RexImpTable.NullAs IS_NULL

Return false if result is not null, true if result is null.

IS_NOT_NULL

public static final RexImpTable.NullAs IS_NOT_NULL

Return true if result is not null, false if result is null.

Method Detail

values

public static RexImpTable.NullAs[] 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 (RexImpTable.NullAs c : RexImpTable.NullAs.values())
    System.out.println(c);

Returns:

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

valueOf

public static RexImpTable.NullAs 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

of

public static RexImpTable.NullAs of(boolean nullable)

handle

public Expression handle(Expression x)

Adapts an expression with "normal" result to one that adheres to this particular policy.