me.lucko.helper.function.chain

Interface Chain<T>

Type Parameters:

T - the object type

@NonnullByDefault
public interface Chain<T>

A simplified version of Java 8's Stream API.

Chains are not threadsafe or immutable, and should not be reused. They are intended only as a way to reduce boilerplate.

Unlike Streams, Chains are only able to process one object.

Method Summary

Modifier and Type	Method and Description
Chain<T>	apply(Consumer<? super T> action) Applies an action to the backing object
Chain<T>	applyIf(Predicate<? super T> test, Consumer<? super T> action) Applies an action to the backing object if the test passes.
Chain<T>	applyIfNonNull(Consumer<? super T> action) Applies an action to the backing object, if the object is not null.
Optional<T>	end() Gets an optional containing the object backing this chain.
T	endOrNull() Gets the object, or null.
<R> Chain<R>	flatMap(Function<? super T,? extends Chain<? extends R>> mapper) Transforms the backing object, and returns a new chain instance containing the result of the transformation.
<R> Chain<R>	ifElse(Predicate<? super T> test, R passValue, R failValue) Returns a new chain instance containing a new value, depending on if the current object passed the given test.
<R> Chain<R>	map(Function<? super T,? extends R> mapper) Transforms the backing object, and returns a new chain instance containing the result of the transformation.
<R> Chain<R>	mapNullSafe(Function<? super T,? extends R> nonNullMapper, R otherValue) Transforms the backing object and returns a new chain instance containing the result of the transformation, if the backing object is not null.
<R> Chain<R>	mapNullSafeGet(Function<? super T,? extends R> nonNullMapper, Supplier<? extends R> nullSupplier) Transforms the backing object and returns a new chain instance containing the result of the transformation, if the backing object is not null.
<R> Chain<R>	mapOrElse(Predicate<? super T> test, Function<? super T,? extends R> passedMapper, Function<? super T,? extends R> failedMapper) Transforms the backing object, and returns a new chain instance containing the result of the chosen transformation function.
<R> Chain<R>	mapOrElse(Predicate<? super T> test, Function<? super T,? extends R> passedMapper, R otherValue) Transforms the backing object, and returns a new chain instance containing the result of the transformation function, if the test is passed.
Chain<T>	orElse(Predicate<? super T> test, T failValue) Updates the backing object if the test fails, otherwise returns an identical chain.
Chain<T>	orElseGet(Predicate<? super T> test, Supplier<? extends T> failSupplier) Updates the backing object if the test fails, otherwise returns an identical chain.
Chain<T>	orElseGetIfNull(Supplier<? extends T> supplier) Updates the backing object if it is null, otherwise returns an identical chain.
Chain<T>	orElseIfNull(T otherValue) Updates the backing object if it is null, otherwise returns an identical chain.
static <T> Chain<T>	start(T object) Creates a new chain
static <T> Chain<T>	startOpt(Optional<T> optional) Creates a new chain

Method Detail

start

static <T> Chain<T> start(@Nullable
                          T object)

Creates a new chain

Type Parameters:

T - the object type

Parameters:

object - the initial object

Returns:

the new chain

startOpt

static <T> Chain<T> startOpt(@Nonnull
                             Optional<T> optional)

Creates a new chain

Type Parameters:

T - the object type

Parameters:

optional - the initial object

Returns:

the new chain

apply

Chain<T> apply(Consumer<? super T> action)

Applies an action to the backing object

Parameters:

action - the action to apply

Returns:

this chain

applyIf

Chain<T> applyIf(Predicate<? super T> test,
                 Consumer<? super T> action)

Applies an action to the backing object if the test passes.

Parameters:

test - the test

action - the action to apply

Returns:

this chain

applyIfNonNull

Chain<T> applyIfNonNull(Consumer<? super T> action)

Applies an action to the backing object, if the object is not null.

Parameters:

action - the action to apply

Returns:

this chain

orElse

Chain<T> orElse(Predicate<? super T> test,
                T failValue)

Updates the backing object if the test fails, otherwise returns an identical chain.

Parameters:

failValue - the fail value

Returns:

this chain

orElseIfNull

Chain<T> orElseIfNull(T otherValue)

Updates the backing object if it is null, otherwise returns an identical chain.

Parameters:

otherValue - the other value

Returns:

this chain

orElseGet

Chain<T> orElseGet(Predicate<? super T> test,
                   Supplier<? extends T> failSupplier)

Updates the backing object if the test fails, otherwise returns an identical chain.

Parameters:

failSupplier - the fail supplier

Returns:

this chain

orElseGetIfNull

Chain<T> orElseGetIfNull(Supplier<? extends T> supplier)

Updates the backing object if it is null, otherwise returns an identical chain.

Parameters:

supplier - the null supplier

Returns:

this chain

ifElse

<R> Chain<R> ifElse(Predicate<? super T> test,
                    R passValue,
                    R failValue)

Returns a new chain instance containing a new value, depending on if the current object passed the given test.

Type Parameters:

R - the resultant chain type

Parameters:

test - the test

passValue - the value to use if the object passes

failValue - the value to use if the object fails

Returns:

a new chaining containing one of the new values

map

<R> Chain<R> map(Function<? super T,? extends R> mapper)

Transforms the backing object, and returns a new chain instance containing the result of the transformation.

Type Parameters:

R - the resultant chain type

Parameters:

mapper - the mapping function

Returns:

a new chain containing the result of the mapping

mapOrElse

<R> Chain<R> mapOrElse(Predicate<? super T> test,
                       Function<? super T,? extends R> passedMapper,
                       R otherValue)

Transforms the backing object, and returns a new chain instance containing the result of the transformation function, if the test is passed. Otherwise, returns a new chain containing the other replacement value.

Type Parameters:

R - the resultant chain type

Parameters:

test - the test

passedMapper - the function to use if the object passes the test

otherValue - the value to use if the object fails the test

Returns:

a new chain containing the result of the mapping

mapOrElse

<R> Chain<R> mapOrElse(Predicate<? super T> test,
                       Function<? super T,? extends R> passedMapper,
                       Function<? super T,? extends R> failedMapper)

Transforms the backing object, and returns a new chain instance containing the result of the chosen transformation function.

Type Parameters:

R - the resultant chain type

Parameters:

test - the test

passedMapper - the function to use if the object passes the test

failedMapper - the function to use if the object fails the test

Returns:

a new chain containing the result of the mapping

mapNullSafe

<R> Chain<R> mapNullSafe(Function<? super T,? extends R> nonNullMapper,
                         R otherValue)

Transforms the backing object and returns a new chain instance containing the result of the transformation, if the backing object is not null. Otherwise, returns a new chain containing the other value.

Type Parameters:

R - the resultant chain type

Parameters:

nonNullMapper - the function to use if the object is not null

otherValue - the value to use if the object is null

Returns:

a new chain containing the result of the mapping

mapNullSafeGet

<R> Chain<R> mapNullSafeGet(Function<? super T,? extends R> nonNullMapper,
                            Supplier<? extends R> nullSupplier)

Transforms the backing object and returns a new chain instance containing the result of the transformation, if the backing object is not null. Otherwise, returns a new chain containing the result of the supplier.

Type Parameters:

R - the resultant chain type

Parameters:

nonNullMapper - the function to use if the object is not null

nullSupplier - the supplier to use if the object is null

Returns:

a new chain containing the result of the mapping

flatMap

<R> Chain<R> flatMap(Function<? super T,? extends Chain<? extends R>> mapper)

Transforms the backing object, and returns a new chain instance containing the result of the transformation.

Type Parameters:

R - the resultant chain type

Parameters:

mapper - the mapping function

Returns:

the result of the mapping

end

Optional<T> end()

Gets an optional containing the object backing this chain.

Returns:

the object

endOrNull

@Nullable
T endOrNull()

Gets the object, or null.

Returns:

the object (nullable)