org.apache.flink.table.types.utils

Class DataTypeUtils

java.lang.Object

org.apache.flink.table.types.utils.DataTypeUtils

@Internal
public final class DataTypeUtils
extends Object

Utilities for handling DataTypes.

Method Summary

Modifier and Type	Method and Description
static TableSchema	expandCompositeTypeToSchema(DataType dataType) Expands a composite DataType to a corresponding TableSchema.
static DataType	replaceLogicalType(DataType dataType, LogicalType replacement) Replaces the LogicalType of a DataType, i.e., it keeps the bridging class.
static DataType	transform(DataType typeToTransform, TypeTransformation... transformations) Transforms the given data type (can be nested) to a different data type using the given transformations.

Methods inherited from class java.lang.Object

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

Method Detail

replaceLogicalType

public static DataType replaceLogicalType(DataType dataType,
                                          LogicalType replacement)

Replaces the LogicalType of a DataType, i.e., it keeps the bridging class.

transform

public static DataType transform(DataType typeToTransform,
                                 TypeTransformation... transformations)

Transforms the given data type (can be nested) to a different data type using the given transformations. The given transformations will be called in order.

Parameters:

typeToTransform - data type to be transformed.

transformations - the transformations to transform data type to another type.

Returns:

the new data type,

expandCompositeTypeToSchema

public static TableSchema expandCompositeTypeToSchema(DataType dataType)

Expands a composite DataType to a corresponding TableSchema. Useful for flattening a column or mapping a physical to logical type of a table source

Throws an exception for a non composite type. You can use LogicalTypeChecks.isCompositeType(LogicalType) to check that.

It does not expand an atomic type on purpose, because that operation depends on the context. E.g. in case of a FLATTEN function such operation is not allowed, whereas when mapping a physical type to logical the field name should be derived from the logical schema.

Parameters:

dataType - Data type to expand. Must be a composite type.

Returns:

A corresponding table schema.