org.apache.flink.table.types.logical

类 DistinctType

java.lang.Object

org.apache.flink.table.types.logical.LogicalType

org.apache.flink.table.types.logical.UserDefinedType

org.apache.flink.table.types.logical.DistinctType

所有已实现的接口:

Serializable

@PublicEvolving
public final class DistinctType
extends UserDefinedType

Logical type of a user-defined distinct type. A distinct type specifies an identifier and is backed by a source type. A distinct type has the same internal representation as a source type, but is considered to be a separate and incompatible data type for most operations. Compared to the SQL standard, every non-user-defined type can be used as a source type.

A distinct type can always be cast to its source type and vice versa.

Distinct types are implicitly final and do not support super types.

Most other properties are forwarded from the source type. Thus, ordering and comparison among the same distinct types are supported.

The serialized string representation is the fully qualified name of this type which means that the type must have been registered in a catalog.

另请参阅:

序列化表格

嵌套类概要

嵌套类

限定符和类型	类和说明
static class	DistinctType.Builder A builder for a DistinctType.

方法概要

限定符和类型	方法和说明
<R> R	accept(LogicalTypeVisitor<R> visitor)
LogicalType	copy(boolean isNullable) Returns a deep copy of this type with possibly different nullability.
boolean	equals(Object o)
List<LogicalType>	getChildren()
Class<?>	getDefaultConversion() Returns the default conversion class.
LogicalType	getSourceType()
int	hashCode()
static DistinctType.Builder	newBuilder(ObjectIdentifier objectIdentifier, LogicalType sourceType) Creates a builder for a DistinctType.
boolean	supportsInputConversion(Class<?> clazz) Returns whether an instance of the given class can be represented as a value of this logical type when entering the table ecosystem.
boolean	supportsOutputConversion(Class<?> clazz) Returns whether a value of this logical type can be represented as an instance of the given class when leaving the table ecosystem.

从类继承的方法 org.apache.flink.table.types.logical.UserDefinedType

asSerializableString, getDescription, getObjectIdentifier, isFinal

从类继承的方法 org.apache.flink.table.types.logical.LogicalType

asSummaryString, conversionSet, copy, getTypeRoot, isNullable, toString, withNullability

从类继承的方法 java.lang.Object

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

方法详细资料

newBuilder

public static DistinctType.Builder newBuilder(ObjectIdentifier objectIdentifier,
                                              LogicalType sourceType)

Creates a builder for a DistinctType.

getSourceType

public LogicalType getSourceType()

copy

public LogicalType copy(boolean isNullable)

从类复制的说明: LogicalType

Returns a deep copy of this type with possibly different nullability.

指定者:

copy 在类中 LogicalType

参数:

isNullable - the intended nullability of the copied type

返回:

a deep copy

supportsInputConversion

public boolean supportsInputConversion(Class<?> clazz)

从类复制的说明: LogicalType

Returns whether an instance of the given class can be represented as a value of this logical type when entering the table ecosystem. This method helps for the interoperability between JVM-based languages and the relational type system.

A supported conversion directly maps an input class to a logical type without loss of precision or type widening.

For example, java.lang.Long or long can be used as input for BIGINT independent of the set nullability.

指定者:

supportsInputConversion 在类中 LogicalType

参数:

clazz - input class to be converted into this logical type

返回:

flag that indicates if instances of this class can be used as input into the table ecosystem

另请参阅:

LogicalType.getDefaultConversion()

supportsOutputConversion

public boolean supportsOutputConversion(Class<?> clazz)

从类复制的说明: LogicalType

Returns whether a value of this logical type can be represented as an instance of the given class when leaving the table ecosystem. This method helps for the interoperability between JVM-based languages and the relational type system.

A supported conversion directly maps a logical type to an output class without loss of precision or type widening.

For example, java.lang.Long or long can be used as output for BIGINT if the type is not nullable. If the type is nullable, only java.lang.Long can represent this.

指定者:

supportsOutputConversion 在类中 LogicalType

参数:

clazz - output class to be converted from this logical type

返回:

flag that indicates if instances of this class can be used as output from the table ecosystem

另请参阅:

LogicalType.getDefaultConversion()

getDefaultConversion

public Class<?> getDefaultConversion()

从类复制的说明: LogicalType

Returns the default conversion class. A value of this logical type is expected to be an instance of the given class when entering or is represented as an instance of the given class when leaving the table ecosystem if no other conversion has been specified.

For example, java.lang.Long is the default input and output for BIGINT.

指定者:

getDefaultConversion 在类中 LogicalType

返回:

default class to represent values of this logical type

另请参阅:

LogicalType.supportsInputConversion(Class), LogicalType.supportsOutputConversion(Class)

getChildren

public List<LogicalType> getChildren()

指定者:

getChildren 在类中 LogicalType

accept

public <R> R accept(LogicalTypeVisitor<R> visitor)

指定者:

accept 在类中 LogicalType

equals

public boolean equals(Object o)

覆盖:

equals 在类中 UserDefinedType

hashCode

public int hashCode()

覆盖:

hashCode 在类中 UserDefinedType