org.jooq.tools

Class Convert

java.lang.Object

org.jooq.tools.Convert

public final class Convert
extends Object

Utility methods for type conversions

This class provides less type-safety than the general jOOQ API methods. For instance, it accepts arbitrary Converter objects in methods like convert(Collection, Converter) and convert(Object, Class), trying to retrofit the Object argument to the type provided in Converter.fromType() before performing the actual conversion.

Author:

Lukas Eder

Field Summary

Fields

Modifier and Type	Field and Description
static Set<String>	FALSE_VALUES All string values that can be transformed into a boolean false value.
static Set<String>	TRUE_VALUES All string values that can be transformed into a boolean true value.

Method Summary

Modifier and Type	Method and Description
static <T> List<T>	convert(Collection<?> collection, Class<? extends T> type) Convert a collection of objects to a list of T, using convert(Object, Class)
static <U> List<U>	convert(Collection<?> collection, Converter<?,? extends U> converter) Convert a collection of objects to a list of T, using convert(Object, Converter)
static Object[]	convert(Object[] values, Class<?>[] types) Convert an array of values to a matching data type This converts values[i] to types[i]
static Object[]	convert(Object[] values, Field<?>[] fields) Convert an array of values to a matching data type This converts values[i] to fields[i].getType()
static <T> T	convert(Object from, Class<? extends T> toClass) Convert an object to a type.
static <U> U	convert(Object from, Converter<?,? extends U> converter) Convert an object to a type.
static Object[]	convertArray(Object[] from, Class<?> toClass) Convert an array into another one by these rules If toClass is not an array class, then make it an array class first If toClass is an array class, then create an instance from it, and convert all elements in the from array one by one, using convert(Object, Class)
static <U> U[]	convertArray(Object[] from, Converter<?,? extends U> converter) Convert an array into another one using a converter This uses convertArray(Object[], Class) to convert the array to an array of Converter.fromType() first, before converting that array again to Converter.toType()
static <U> U[]	convertCollection(Collection from, Class<? extends U[]> to)

Methods inherited from class java.lang.Object

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

Field Detail

TRUE_VALUES

public static final Set<String> TRUE_VALUES

All string values that can be transformed into a boolean true value.

FALSE_VALUES

public static final Set<String> FALSE_VALUES

All string values that can be transformed into a boolean false value.

Method Detail

convert

public static final Object[] convert(Object[] values,
                                     Field<?>[] fields)

Convert an array of values to a matching data type

This converts values[i] to fields[i].getType()

convert

public static final Object[] convert(Object[] values,
                                     Class<?>[] types)

Convert an array of values to a matching data type

This converts values[i] to types[i]

convertArray

public static final <U> U[] convertArray(Object[] from,
                                         Converter<?,? extends U> converter)
                                  throws DataTypeException

Convert an array into another one using a converter

This uses convertArray(Object[], Class) to convert the array to an array of Converter.fromType() first, before converting that array again to Converter.toType()

Parameters:

from - The array to convert

converter - The data type converter

Returns:

A converted array

Throws:

DataTypeException - - When the conversion is not possible

convertArray

public static final Object[] convertArray(Object[] from,
                                          Class<?> toClass)
                                   throws DataTypeException

Convert an array into another one by these rules

• If toClass is not an array class, then make it an array class first
• If toClass is an array class, then create an instance from it, and convert all elements in the from array one by one, using convert(Object, Class)

Parameters:

from - The array to convert

toClass - The target array type

Returns:

A converted array

Throws:

DataTypeException - - When the conversion is not possible

convertCollection

public static final <U> U[] convertCollection(Collection from,
                                              Class<? extends U[]> to)

convert

public static final <U> U convert(Object from,
                                  Converter<?,? extends U> converter)
                           throws DataTypeException

Convert an object to a type.

Parameters:

from - The source object

converter - The data type converter

Returns:

The target type object

Throws:

DataTypeException - - When the conversion is not possible

convert

public static final <T> T convert(Object from,
                                  Class<? extends T> toClass)
                           throws DataTypeException

Convert an object to a type. These are the conversion rules:

• null is always converted to null, regardless of the target type.
• Identity conversion (converting a value to its own type) is always possible.
• All types can be converted to String
• All types can be converted to Object
• All Number types can be converted to other Number types
• All Number or String types can be converted to Boolean. Possible (case-insensitive) values for true:
  • 1
  • 1.0
  • y
  • yes
  • true
  • on
  • enabled

  Possible (case-insensitive) values for false:

  • 0
  • 0.0
  • n
  • no
  • false
  • off
  • disabled

  All other values evaluate to null

• All Date subtypes (Date, Time, Timestamp), as well as most Temporal subtypes ( LocalDate, LocalTime, LocalDateTime, OffsetTime, OffsetDateTime, as well as Instant) can be converted into each other.
• All String types can be converted into URI, URL and File
• Primitive target types behave like their wrapper types, except that null is converted into the initialisation value (e.g. 0 for int, false for boolean)
• byte[] can be converted into String, using the platform's default charset
• Object[] can be converted into any other array type, if array elements can be converted, too
• All other combinations that are not listed above will result in a DataTypeException

Parameters:

from - The object to convert

toClass - The target type

Returns:

The converted object

Throws:

DataTypeException - - When the conversion is not possible

convert

public static final <T> List<T> convert(Collection<?> collection,
                                        Class<? extends T> type)
                                 throws DataTypeException

Convert a collection of objects to a list of T, using convert(Object, Class)

Parameters:

collection - The list of objects

type - The target type

Returns:

The list of converted objects

Throws:

DataTypeException - - When the conversion is not possible

See Also:

convert(Object, Class)

convert

public static final <U> List<U> convert(Collection<?> collection,
                                        Converter<?,? extends U> converter)
                                 throws DataTypeException

Convert a collection of objects to a list of T, using convert(Object, Converter)

Parameters:

collection - The collection of objects

converter - The data type converter

Returns:

The list of converted objects

Throws:

DataTypeException - - When the conversion is not possible

See Also:

convert(Object, Converter)