Package smile.data.type

Interface DataType

All Superinterfaces:
Serializable
All Known Implementing Classes:
ArrayType, BooleanType, ByteType, CharType, DateTimeType, DateType, DecimalType, DoubleType, FloatType, IntType, LongType, ObjectType, PrimitiveType, ShortType, StringType, StructType, TimeType
public interface DataType extends Serializable
The interface of data types.

  • Nested Class Summary

    Nested Classes
    Modifier and Type
    Interface
    Description
    static enum 
    DataType.ID
    Data type ID.

  • Method Summary

    Modifier and Type
    Method
    Description
    static DataType
    coerce(DataType a, DataType b)
    Returns the common type.
    DataType.ID
    id()
    Returns the type ID enum.
    static DataType
    infer(String s)
    Infers the type of string.
    default boolean
    isBoolean()
    Returns true if the type is boolean or Boolean.
    default boolean
    isByte()
    Returns true if the type is byte or Byte.
    default boolean
    isChar()
    Returns true if the type is char or Char.
    default boolean
    isDecimal()
    Returns true if the type is decimal.
    default boolean
    isDouble()
    Returns true if the type is double or Double.
    default boolean
    isFloat()
    Returns true if the type is float or Float.
    default boolean
    isFloating()
    Returns true if the type is float or double.
    default boolean
    isInt()
    Returns true if the type is int or Integer.
    default boolean
    isIntegral()
    Returns true if the type is int, long, short or byte.
    default boolean
    isLong()
    Returns true if the type is long or Long.
    default boolean
    isNullable()
    Returns true if the data may be null.
    default boolean
    isNumeric()
    Returns true if the type is numeric (integral or floating).
    default boolean
    isObject()
    Returns true if the type is ObjectType.
    default boolean
    isPrimitive()
    Returns true if this is a primitive data type.
    default boolean
    isShort()
    Returns true if the type is short or Short.
    default boolean
    isString()
    Returns true if the type is String.
    String
    name()
    Returns the type name used in external catalogs.
    static DataType
    of(Class<?> clazz)
    Returns the DataType of a class.
    static DataType
    of(String s)
    Returns a DataType from its string representation.
    static DataType
    of(JDBCType type, boolean nullable, String dbms)
    Returns the DataType of a JDBC type.
    static DataType
    prompt(DataType a, DataType b)
    Type promotion when apply to expressions.
    default String
    toString(Object o)
    Returns the string representation of a value of the type.
    Object
    valueOf(String s)
    Returns the value from its string representation.

  • Method Details

    • id

      DataType.ID id()
      Returns the type ID enum.
      Returns:
      the type ID enum.

    • name

      String name()
      Returns the type name used in external catalogs. DataType.of(name()) should return the same type.
      Returns:
      the type name used in external catalogs.

    • valueOf

      Object valueOf(String s)
      Returns the value from its string representation.
      Parameters:
      s - the string representation of a value of this type.
      Returns:
      the value.

    • toString

      default String toString(Object o)
      Returns the string representation of a value of the type.
      Parameters:
      o - the value.
      Returns:
      the string representation

    • isNullable

      default boolean isNullable()
      Returns true if the data may be null.
      Returns:
      true if the data may be null.

    • isPrimitive

      default boolean isPrimitive()
      Returns true if this is a primitive data type.
      Returns:
      true if this is a primitive data type.

    • isFloating

      default boolean isFloating()
      Returns true if the type is float or double.
      Returns:
      true if the type is float or double.

    • isIntegral

      default boolean isIntegral()
      Returns true if the type is int, long, short or byte.
      Returns:
      true if the type is int, long, short or byte.

    • isNumeric

      default boolean isNumeric()
      Returns true if the type is numeric (integral or floating).
      Returns:
      true if the type is numeric (integral or floating).

    • isBoolean

      default boolean isBoolean()
      Returns true if the type is boolean or Boolean.
      Returns:
      true if the type is boolean or Boolean.

    • isChar

      default boolean isChar()
      Returns true if the type is char or Char.
      Returns:
      true if the type is char or Char.

    • isByte

      default boolean isByte()
      Returns true if the type is byte or Byte.
      Returns:
      true if the type is byte or Byte.

    • isShort

      default boolean isShort()
      Returns true if the type is short or Short.
      Returns:
      true if the type is short or Short.

    • isInt

      default boolean isInt()
      Returns true if the type is int or Integer.
      Returns:
      true if the type is int or Integer.

    • isLong

      default boolean isLong()
      Returns true if the type is long or Long.
      Returns:
      true if the type is long or Long.

    • isDecimal

      default boolean isDecimal()
      Returns true if the type is decimal.
      Returns:
      true if the type is decimal.

    • isFloat

      default boolean isFloat()
      Returns true if the type is float or Float.
      Returns:
      true if the type is float or Float.

    • isDouble

      default boolean isDouble()
      Returns true if the type is double or Double.
      Returns:
      true if the type is double or Double.

    • isString

      default boolean isString()
      Returns true if the type is String.
      Returns:
      true if the type is String.

    • isObject

      default boolean isObject()
      Returns true if the type is ObjectType.
      Returns:
      true if the type is ObjectType.

    • prompt

      static DataType prompt(DataType a, DataType b)
      Type promotion when apply to expressions. First, all byte, short, and char values are promoted to int. Then, if one operand is a long, the whole expression is promoted to long. If one operand is a float, the entire expression is promoted to float. If any of the operands is double, the result is double.
      Parameters:
      a - the data type.
      b - the data type.
      Returns:
      the promoted type.

    • coerce

      static DataType coerce(DataType a, DataType b)
      Returns the common type. This method is intended to be used for inferring the schema from text files. This is NOT a general implementation of type coercion.
      Parameters:
      a - the data type.
      b - the data type.
      Returns:
      the common type.

    • infer

      static DataType infer(String s)
      Infers the type of string.
      Parameters:
      s - the string value.
      Returns:
      the inferred data type of string value.

    • of

      static DataType of(String s) throws ClassNotFoundException
      Returns a DataType from its string representation.
      Parameters:
      s - the string representation of data type.
      Returns:
      the data type.
      Throws:
      ClassNotFoundException - when fails to load a class.

    • of

      static DataType of(Class<?> clazz)
      Returns the DataType of a class.
      Parameters:
      clazz - the Class object.
      Returns:
      Smile data type.

    • of

      static DataType of(JDBCType type, boolean nullable, String dbms)
      Returns the DataType of a JDBC type.
      Parameters:
      type - the JDBC data type.
      nullable - true if the column value may be null.
      dbms - The database product name.
      Returns:
      Smile data type.