Package org.apache.druid.math.expr

Class ExpressionType

java.lang.Object

org.apache.druid.segment.column.BaseTypeSignature<ExprType>

org.apache.druid.math.expr.ExpressionType

All Implemented Interfaces:

TypeSignature<ExprType>

@Immutable
public class ExpressionType
extends BaseTypeSignature<ExprType>

The type system used to process Druid expressions. This is basically ColumnType, but without ColumnType.FLOAT because the expression processing system does not currently directly support them.

Field Summary

Fields

Modifier and Type	Field	Description
static final ExpressionType	DOUBLE
static final ExpressionType	DOUBLE_ARRAY
static final ExpressionType	LONG
static final ExpressionType	LONG_ARRAY
static final ExpressionType	NESTED_DATA
static final ExpressionType	STRING
static final ExpressionType	STRING_ARRAY
static final ExpressionType	UNKNOWN_COMPLEX

Fields inherited from class org.apache.druid.segment.column.BaseTypeSignature

complexTypeName, elementType, type

Constructor Summary

Constructors

Constructor	Description
ExpressionType(ExprType exprType, String complexTypeName, ExpressionType elementType)

Method Summary

Modifier and Type	Method	Description
static ExpressionType	asArrayType(ExpressionType elementType)	Convert a primitive ExpressionType into an array of that type.
static ExpressionType	elementType(ExpressionType type)	If an ExpressionType is an array, return BaseTypeSignature.getElementType(), otherwise the type is returned unchanged.
static ExpressionType	fromColumnType(TypeSignature<ValueType> valueType)	The expression system does not distinguish between ValueType.FLOAT and ValueType.DOUBLE, so this method will convert ValueType.FLOAT to DOUBLE.
static ExpressionType	fromColumnTypeStrict(TypeSignature<ValueType> valueType)	The expression system does not distinguish between ValueType.FLOAT and ValueType.DOUBLE, so, this method will convert ValueType.FLOAT to DOUBLE.
static ExpressionType	fromString(String typeName)
static ColumnType	toColumnType(ExpressionType exprType)	Convert ExpressionType to the corresponding ColumnType

Methods inherited from class org.apache.druid.segment.column.BaseTypeSignature

equals, getComplexTypeName, getElementType, getNullableStrategy, getStrategy, getType, hashCode, toString

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.apache.druid.segment.column.TypeSignature

anyOf, asTypeString, is, isArray, isNumeric, isPrimitive, isPrimitiveArray

Field Details

STRING

public static final ExpressionType STRING

LONG

public static final ExpressionType LONG

DOUBLE

public static final ExpressionType DOUBLE

STRING_ARRAY

public static final ExpressionType STRING_ARRAY

LONG_ARRAY

public static final ExpressionType LONG_ARRAY

DOUBLE_ARRAY

public static final ExpressionType DOUBLE_ARRAY

NESTED_DATA

public static final ExpressionType NESTED_DATA

UNKNOWN_COMPLEX

public static final ExpressionType UNKNOWN_COMPLEX

Constructor Details

ExpressionType

public ExpressionType(ExprType exprType,
 @Nullable
 String complexTypeName,
 @Nullable
 ExpressionType elementType)

Method Details

fromString

@Nullable
public static ExpressionType fromString(@Nullable
 String typeName)

elementType

@Nullable
public static ExpressionType elementType(@Nullable
 ExpressionType type)

If an ExpressionType is an array, return BaseTypeSignature.getElementType(), otherwise the type is returned unchanged.

asArrayType

@Nullable
public static ExpressionType asArrayType(@Nullable
 ExpressionType elementType)

Convert a primitive ExpressionType into an array of that type. Non-primitive types are passed through, even if they are not arrays.

fromColumnTypeStrict

public static ExpressionType fromColumnTypeStrict(@Nullable
 TypeSignature<ValueType> valueType)

The expression system does not distinguish between ValueType.FLOAT and ValueType.DOUBLE, so, this method will convert ValueType.FLOAT to DOUBLE. Null values are not allowed in this method, and will result in an IllegalStateException

Throws:

IllegalStateException

fromColumnType

@Nullable
public static ExpressionType fromColumnType(@Nullable
 TypeSignature<ValueType> valueType)

The expression system does not distinguish between ValueType.FLOAT and ValueType.DOUBLE, so this method will convert ValueType.FLOAT to DOUBLE.

toColumnType

public static ColumnType toColumnType(ExpressionType exprType)

Convert ExpressionType to the corresponding ColumnType