Package org.instancio.generators

Interface ValueSpecs

All Superinterfaces:

CommonGeneratorSpecs

All Known Subinterfaces:

InstancioGenApi

public interface ValueSpecs
extends CommonGeneratorSpecs

Defines all built-in generators that are available via the Instancio.gen() method.

Since:

5.0.0

Method Summary

Modifier and Type	Method	Description
BooleanSpec	booleans()	Generator for Boolean values.
ByteSpec	bytes()	Generator for Byte values.
CharacterSpec	chars()	Generator for Character values.
ChecksumSpecs	checksum()	Provides access to checksum generators.
DoubleSpec	doubles()	Generator for Double values.
<E extends Enum<E>> EnumSpec<E>	enumOf(Class<E> enumClass)	Generator for enum values.
FinanceSpecs	finance()	Provides access to finance-related generators.
FloatSpec	floats()	Generator for Float values.
HashSpec	hash()	Generator for various types of hashes.
IdSpecs	id()	Provides access to identifier generators.
<T> IntervalSpec<T>	intervalStarting(T startingValue)	A spec for generating intervals of various types, such as numeric and temporal values.
IntegerSpec	ints()	Generator for Integer values.
NumericSequenceSpec<Integer>	intSeq()	An Integer sequence generator.
IoSpecs	io()	Provides access to IO generators.
LongSpec	longs()	Generator for Long values.
NumericSequenceSpec<Long>	longSeq()	A Long sequence generator.
MathSpecs	math()	Provides generators for java.math classes.
NetSpecs	net()	Provides generators for java.net classes.
NioSpecs	nio()	Provides access to NIO generators.
<T> OneOfCollectionSpec<T>	oneOf(Collection<T> choices)	Picks a random value from the given choices.
<T> OneOfArraySpec<T>	oneOf(T... choices)	Picks a random value from the given choices.
ShortSpec	shorts()	Generator for Short values.
<T> ShuffleSpec<T>	shuffle(Collection<T> collection)	Creates a copy of the specified collection and shuffles its elements.
<T> ShuffleSpec<T>	shuffle(T... array)	Creates a copy of the specified array and shuffles its elements.
SpatialSpecs	spatial()	Provides access to spatial data type related generators.
StringSpec	string()	Generator for String values.
TemporalSpecs	temporal()	Provides access to temporal generators.
TextSpecs	text()	Provides access to text generators.
UUIDSpec	uuid()	Generator for UUID values.

Method Details

booleans

BooleanSpec booleans()

Generator for Boolean values.

Specified by:

booleans in interface CommonGeneratorSpecs

Returns:

API builder reference

Since:

5.0.0

chars

CharacterSpec chars()

Generator for Character values.

Specified by:

chars in interface CommonGeneratorSpecs

Returns:

API builder reference

Since:

5.0.0

string

StringSpec string()

Generator for String values.

Specified by:

string in interface CommonGeneratorSpecs

Returns:

API builder reference

Since:

5.0.0

bytes

ByteSpec bytes()

Generator for Byte values.

Specified by:

bytes in interface CommonGeneratorSpecs

Returns:

API builder reference

Since:

5.0.0

shorts

ShortSpec shorts()

Generator for Short values.

Specified by:

shorts in interface CommonGeneratorSpecs

Returns:

API builder reference

Since:

5.0.0

ints

IntegerSpec ints()

Generator for Integer values.

Specified by:

ints in interface CommonGeneratorSpecs

Returns:

API builder reference

Since:

5.0.0

intSeq

NumericSequenceSpec<Integer> intSeq()

An Integer sequence generator.

Specified by:

intSeq in interface CommonGeneratorSpecs

Returns:

API builder reference

Since:

5.0.0

longs

LongSpec longs()

Generator for Long values.

Specified by:

longs in interface CommonGeneratorSpecs

Returns:

API builder reference

Since:

5.0.0

longSeq

NumericSequenceSpec<Long> longSeq()

A Long sequence generator.

Specified by:

longSeq in interface CommonGeneratorSpecs

Returns:

API builder reference

Since:

5.0.0

floats

FloatSpec floats()

Generator for Float values.

Specified by:

floats in interface CommonGeneratorSpecs

Returns:

API builder reference

Since:

5.0.0

doubles

DoubleSpec doubles()

Generator for Double values.

Specified by:

doubles in interface CommonGeneratorSpecs

Returns:

API builder reference

Since:

5.0.0

enumOf

<E extends Enum<E>> EnumSpec<E> enumOf(Class<E> enumClass)

Generator for enum values.

Specified by:

enumOf in interface CommonGeneratorSpecs

Type Parameters:

E - enum type

Parameters:

enumClass - type of enum to generate

Returns:

API builder reference

Since:

5.0.0

oneOf

<T> OneOfArraySpec<T> oneOf(T... choices)

Picks a random value from the given choices.

Specified by:

oneOf in interface CommonGeneratorSpecs

Type Parameters:

T - element type

Parameters:

choices - to choose from

Returns:

API builder reference

Since:

5.0.0

oneOf

<T> OneOfCollectionSpec<T> oneOf(Collection<T> choices)

Picks a random value from the given choices.

Specified by:

oneOf in interface CommonGeneratorSpecs

Type Parameters:

T - element type

Parameters:

choices - to choose from

Returns:

API builder reference

Since:

5.0.0

intervalStarting

@ExperimentalApi
<T> IntervalSpec<T> intervalStarting(T startingValue)

A spec for generating intervals of various types, such as numeric and temporal values.

Generating intervals requires three inputs:

• The start value of the first interval
• A function to calculate the end value based on the last start value
• A function to calculate the subsequent start value based on the last end value

To illustrate with an example, we will generate a list of vacations defined as:

 record Vacation(LocalDate start, LocalDate end) {}
 

The first vacation should start on 2000-01-01. Each vacation should last between 1-3 weeks. There should be 12-15 months between vacations.

 IntervalSupplier<LocalDate> intervals = Instancio.gen()
     .intervalStarting(LocalDate.of(2000, 1, 1))
     .nextStart((end, random) -> end.plusMonths(random.intRange(12, 15)))
     .nextEnd((start, random) -> start.plusWeeks(random.intRange(1, 3)))
     .get();
 

This method produces an IntervalSupplier containing start and end methods, which return a Supplier. Each call to start() and end() will produce new interval values.

 for (int i = 0; i < 4; i++) {
     System.out.println(interval.start().get() + " - " + interval.end().get());
 }
 // Sample output:
 // 2000-01-01 - 2000-01-15
 // 2001-02-15 - 2001-03-08
 // 2002-03-08 - 2002-03-15
 // 2003-06-15 - 2003-07-06
 

The start() and end() can be used to populate Vacation objects, for example:

 List<Vacation> vacations = Instancio.ofList(Vacation.class)
     .size(4)
     .supply(field(Vacation::start), intervals.start())
     .supply(field(Vacation::end), intervals.end())
     .create();
 

Type Parameters:

T - the type of value underlying the interval

Parameters:

startingValue - the starting value of the first interval

Returns:

API builder reference

Since:

5.0.0

See Also:

• IntervalSupplier

shuffle

@ExperimentalApi
<T> ShuffleSpec<T> shuffle(T... array)

Creates a copy of the specified array and shuffles its elements.

Type Parameters:

T - the element type

Parameters:

array - containing the elements to shuffle

Returns:

API builder reference

Since:

5.0.0

shuffle

@ExperimentalApi
<T> ShuffleSpec<T> shuffle(Collection<T> collection)

Creates a copy of the specified collection and shuffles its elements.

Type Parameters:

T - the element type

Parameters:

collection - containing the elements to shuffle

Returns:

API builder reference

Since:

5.0.0

io

IoSpecs io()

Provides access to IO generators.

Specified by:

io in interface CommonGeneratorSpecs

Returns:

API builder reference

Since:

5.0.0

math

MathSpecs math()

Provides generators for java.math classes.

Specified by:

math in interface CommonGeneratorSpecs

Returns:

API builder reference

Since:

5.0.0

net

NetSpecs net()

Provides generators for java.net classes.

Specified by:

net in interface CommonGeneratorSpecs

Returns:

API builder reference

Since:

5.0.0

nio

NioSpecs nio()

Provides access to NIO generators.

Specified by:

nio in interface CommonGeneratorSpecs

Returns:

API builder reference

Since:

5.0.0

temporal

TemporalSpecs temporal()

Provides access to temporal generators.

Specified by:

temporal in interface CommonGeneratorSpecs

Returns:

API builder reference

Since:

5.0.0

text

TextSpecs text()

Provides access to text generators.

Specified by:

text in interface CommonGeneratorSpecs

Returns:

API builder reference

Since:

5.0.0

uuid

UUIDSpec uuid()

Generator for UUID values.

Since:

5.0.0

checksum

ChecksumSpecs checksum()

Provides access to checksum generators.

Specified by:

checksum in interface CommonGeneratorSpecs

Returns:

API builder reference

Since:

5.0.0

id

IdSpecs id()

Provides access to identifier generators.

Specified by:

id in interface CommonGeneratorSpecs

Returns:

API builder reference

Since:

5.0.0

hash

HashSpec hash()

Generator for various types of hashes.

Specified by:

hash in interface CommonGeneratorSpecs

Returns:

API builder reference

Since:

5.0.0

finance

FinanceSpecs finance()

Provides access to finance-related generators.

Specified by:

finance in interface CommonGeneratorSpecs

Returns:

API builder reference

Since:

5.0.0

spatial

SpatialSpecs spatial()

Provides access to spatial data type related generators.

Specified by:

spatial in interface CommonGeneratorSpecs

Returns:

API builder reference

Since:

5.0.0