Class Functions

java.lang.Object

org.tquadrat.foundation.function.Functions

@UtilityClass
@ClassVersion(sourceVersion="$Id: Functions.java 1163 2026-03-20 15:28:33Z tquadrat $")
public final class Functions
extends Object

Some helper methods for the use with lambdas and functional interfaces.

TCE Wrapper

The methods of the functional interfaces in the package java.util.function do not declare any checked exceptions - for good reasons, of course. But sometimes, it would be nice to have that capability.

Using the wrapper methods in this class, you can achieve that like this:

…
import static org.tquadrat.foundation.function.Functions.*;
…

…
Appendable appendable = …
Consumer appender = wrapConsumer( s -> appendable.append( s ) );
…

…
try
{
  appender.accept( "…" );
}
catch( LambdaContainerException e )
{
  throw (IOException) e.getCause();
}
…

"TCE" stands for "Throws Checked Exception".

Author:

Thomas Thrien (thomas.thrien@tquadrat.org)

Version:

$Id: Functions.java 1163 2026-03-20 15:28:33Z tquadrat $

Since:

0.0.5

UML Diagram

⁠

UML Diagram for "org.tquadrat.foundation.function.Functions"

⁠

Constructor Summary

Constructors

Modifier	Constructor	Description
private	Functions()	No instance allowed for this class.

Method Summary

Modifier and Type	Method	Description
static final <T1,T2> BiConsumer<T1,T2>	wrapBiConsumer(TCEBiConsumer<? super T1, ? super T2> consumer)	Wraps an instance of TCEBiConsumer to an instance of BiConsumer that throws an instance of LambdaContainerException with the causing exception, in case the wrapped instance emitted a checked exception.
static final <T1,T2,R> BiFunction<T1,T2,R>	wrapBiFunction(TCEBiFunction<? super T1, ? super T2, ? extends R> function)	Wraps an instance of TCEBiFunction to an instance of BiFunction that throws an instance of LambdaContainerException with the causing exception, in case the wrapped instance emitted a checked exception.
static final <T> BinaryOperator<T>	wrapBinaryOperator(TCEBinaryOperator<T> function)	Wraps an instance of TCEBinaryOperator to an instance of BinaryOperator that throws an instance of LambdaContainerException with the causing exception, in case the wrapped instance emitted a checked exception.
static final <T> Consumer<T>	wrapConsumer(TCEConsumer<? super T> consumer)	Wraps an instance of TCEConsumer to an instance of Consumer that throws an instance of LambdaContainerException with the causing exception, in case the wrapped instance emitted a checked exception.
static final <T,R> Function<T,R>	wrapFunction(TCEFunction<? super T, ? extends R> function)	Wraps an instance of TCEFunction to an instance of Function that throws an instance of LambdaContainerException with the causing exception, in case the wrapped instance emitted a checked exception.
static final <T> Predicate<T>	wrapPredicate(TCEPredicate<? super T> predicate)	Wraps an instance of TCEPredicate to an instance of Predicate that throws an instance of LambdaContainerException with the causing exception, in case the wrapped instance emitted a checked exception.
static final <T> Supplier<T>	wrapSupplier(TCESupplier<? extends T> supplier)	Wraps an instance of TCESupplier to an instance of Supplier that throws an instance of LambdaContainerException with the causing exception, in case the wrapped instance emitted a checked exception.
static final <T1,T2,T3> TriConsumer<T1,T2,T3>	wrapTriConsumer(TCETriConsumer<? super T1, ? super T2, ? super T3> consumer)	Wraps an instance of TCETriConsumer to an instance of TriConsumer that throws an instance of LambdaContainerException with the causing exception, in case the wrapped instance emitted a checked exception.
static final <T1,T2,T3,R> TriFunction<T1,T2,T3,R>	wrapTriFunction(TCETriFunction<? super T1, ? super T2, ? super T3, ? extends R> function)	Wraps an instance of TCETriFunction to an instance of TriFunction that throws an instance of LambdaContainerException with the causing exception, in case the wrapped instance emitted a checked exception.

Methods inherited from class Object

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

Constructor Details

Functions

private Functions()

No instance allowed for this class.

Method Details

wrapBiConsumer

@API(status=STABLE,
     since="0.0.5")
public static final <T1,T2> BiConsumer<T1,T2> wrapBiConsumer(TCEBiConsumer<? super T1, ? super T2> consumer)

Wraps an instance of TCEBiConsumer to an instance of BiConsumer that throws an instance of LambdaContainerException with the causing exception, in case the wrapped instance emitted a checked exception.

Type Parameters:

T1 - The type of the first argument taken by the consumer.

T2 - The type of the second argument taken by the consumer.

Parameters:

consumer - The consumer to wrap.

Returns:

The wrapped consumer.

wrapBiFunction

@API(status=STABLE,
     since="0.0.5")
public static final <T1,T2,R> BiFunction<T1,T2,R> wrapBiFunction(TCEBiFunction<? super T1, ? super T2, ? extends R> function)

Wraps an instance of TCEBiFunction to an instance of BiFunction that throws an instance of LambdaContainerException with the causing exception, in case the wrapped instance emitted a checked exception.

Type Parameters:

T1 - The type of the first argument to the function.

T2 - The type of the second argument to the function.

R - The type of the result of the function.

Parameters:

function - The function to wrap.

Returns:

The wrapped function.

wrapBinaryOperator

@API(status=STABLE,
     since="0.0.5")
public static final <T> BinaryOperator<T> wrapBinaryOperator(TCEBinaryOperator<T> function)

Wraps an instance of TCEBinaryOperator to an instance of BinaryOperator that throws an instance of LambdaContainerException with the causing exception, in case the wrapped instance emitted a checked exception.

Type Parameters:

T - The type of the operands and result of the operator.

Parameters:

function - The function to wrap.

Returns:

The wrapped function.

wrapConsumer

@API(status=STABLE,
     since="0.0.5")
public static final <T> Consumer<T> wrapConsumer(TCEConsumer<? super T> consumer)

Wraps an instance of TCEConsumer to an instance of Consumer that throws an instance of LambdaContainerException with the causing exception, in case the wrapped instance emitted a checked exception.

Type Parameters:

T - The type of arguments taken by the consumer.

Parameters:

consumer - The consumer to wrap.

Returns:

The wrapped consumer.

wrapFunction

@API(status=STABLE,
     since="0.0.5")
public static final <T,R> Function<T,R> wrapFunction(TCEFunction<? super T, ? extends R> function)

Wraps an instance of TCEFunction to an instance of Function that throws an instance of LambdaContainerException with the causing exception, in case the wrapped instance emitted a checked exception.

Type Parameters:

T - The type of the input to the function.

R - The type of the result of the function.

Parameters:

function - The function to wrap.

Returns:

The wrapped function.

wrapPredicate

@API(status=STABLE,
     since="0.0.5")
public static final <T> Predicate<T> wrapPredicate(TCEPredicate<? super T> predicate)

Wraps an instance of TCEPredicate to an instance of Predicate that throws an instance of LambdaContainerException with the causing exception, in case the wrapped instance emitted a checked exception.

Type Parameters:

T - The type of the input to the predicate.

Parameters:

predicate - The predicate to wrap.

Returns:

The wrapped predicate.

wrapSupplier

@API(status=STABLE,
     since="0.0.5")
public static final <T> Supplier<T> wrapSupplier(TCESupplier<? extends T> supplier)

Wraps an instance of TCESupplier to an instance of Supplier that throws an instance of LambdaContainerException with the causing exception, in case the wrapped instance emitted a checked exception.

Type Parameters:

T - The type of results supplied by the supplier.

Parameters:

supplier - The supplier to wrap.

Returns:

The wrapped supplier.

wrapTriConsumer

@API(status=STABLE,
     since="0.0.5")
public static final <T1,T2,T3>
TriConsumer<T1,T2,T3> wrapTriConsumer(TCETriConsumer<? super T1, ? super T2, ? super T3> consumer)

Wraps an instance of TCETriConsumer to an instance of TriConsumer that throws an instance of LambdaContainerException with the causing exception, in case the wrapped instance emitted a checked exception.

Type Parameters:

T1 - The type of the first argument taken by the consumer.

T2 - The type of the second argument taken by the consumer.

T3 - The type of the third argument taken by the consumer.

Parameters:

consumer - The consumer to wrap.

Returns:

The wrapped consumer.

wrapTriFunction

@API(status=STABLE,
     since="0.0.5")
public static final <T1,T2,T3,R>
TriFunction<T1,T2,T3,R> wrapTriFunction(TCETriFunction<? super T1, ? super T2, ? super T3, ? extends R> function)

Wraps an instance of TCETriFunction to an instance of TriFunction that throws an instance of LambdaContainerException with the causing exception, in case the wrapped instance emitted a checked exception.

Type Parameters:

T1 - The type of the first argument taken by the function.

T2 - The type of the second argument taken by the function.

T3 - The type of the third argument taken by the function.

R - The type of the result of the function.

Parameters:

function - The function to wrap.

Returns:

The wrapped function.