org.apache.drill.exec.expr.fn

Class FunctionGenerationHelper

java.lang.Object

org.apache.drill.exec.expr.fn.FunctionGenerationHelper

public class FunctionGenerationHelper
extends Object

Field Summary

Fields

Modifier and Type	Field and Description
static String	COMPARE_TO_NULLS_HIGH
static String	COMPARE_TO_NULLS_LOW

Constructor Summary

Constructors

Constructor and Description
FunctionGenerationHelper()

Method Summary

Methods

Modifier and Type	Method and Description
static FunctionHolderExpression	getFunctionExpression(String name, TypeProtos.MajorType returnType, FunctionImplementationRegistry registry, ClassGenerator.HoldingContainer... args)
static FunctionHolderExpression	getOrderingComparator(boolean null_high, ClassGenerator.HoldingContainer left, ClassGenerator.HoldingContainer right, FunctionImplementationRegistry registry) Finds ordering comparator ("compare_to...") FunctionHolderExpression with a specified ordering for NULL (and considering NULLS equal).
static FunctionHolderExpression	getOrderingComparatorNullsHigh(ClassGenerator.HoldingContainer left, ClassGenerator.HoldingContainer right, FunctionImplementationRegistry registry) Finds ordering comparator ("compare_to...") FunctionHolderExpression with a "NULL high" ordering (and considering NULLS equal).
protected static boolean	isComparableType(TypeProtos.MajorType type)

Methods inherited from class java.lang.Object

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

Field Detail

COMPARE_TO_NULLS_HIGH

public static final String COMPARE_TO_NULLS_HIGH

See Also:

Constant Field Values

COMPARE_TO_NULLS_LOW

public static final String COMPARE_TO_NULLS_LOW

See Also:

Constant Field Values

Constructor Detail

FunctionGenerationHelper

public FunctionGenerationHelper()

Method Detail

getOrderingComparator

public static FunctionHolderExpression getOrderingComparator(boolean null_high,
                                             ClassGenerator.HoldingContainer left,
                                             ClassGenerator.HoldingContainer right,
                                             FunctionImplementationRegistry registry)

Finds ordering comparator ("compare_to...") FunctionHolderExpression with a specified ordering for NULL (and considering NULLS equal).

Parameters:

null_high - whether NULL should compare as the lowest value (if false) or the highest value (if true)

left - ...

right - ...

registry - ...

Returns:

FunctionHolderExpression containing the found function implementation

getOrderingComparatorNullsHigh

public static FunctionHolderExpression getOrderingComparatorNullsHigh(ClassGenerator.HoldingContainer left,
                                                      ClassGenerator.HoldingContainer right,
                                                      FunctionImplementationRegistry registry)

Finds ordering comparator ("compare_to...") FunctionHolderExpression with a "NULL high" ordering (and considering NULLS equal).

Parameters:

left - ...

right - ...

registry - ...

Returns:

FunctionHolderExpression containing the function implementation

See Also:

#getComparator

getFunctionExpression

public static FunctionHolderExpression getFunctionExpression(String name,
                                             TypeProtos.MajorType returnType,
                                             FunctionImplementationRegistry registry,
                                             ClassGenerator.HoldingContainer... args)

isComparableType

protected static boolean isComparableType(TypeProtos.MajorType type)