Module com.github.robtimus.function.throwing

Package com.github.robtimus.function.throwing

Interface ThrowingSupplier<T,X extends Throwable>

Type Parameters:

T - The type of results supplied by this supplier.

X - The type of checked exception that can be thrown.

Functional Interface:

This is a functional interface and can therefore be used as the assignment target for a lambda expression or method reference.

@FunctionalInterface
public interface ThrowingSupplier<T,X extends Throwable>

Represents a supplier of results. This is a checked-exception throwing equivalent of Supplier.

Method Summary

Modifier and Type	Method	Description
static <T,X extends Throwable> ThrowingSupplier<T,X>	checked(Supplier<? extends T> supplier)	Returns a supplier that calls the supplier supplier.
static <T,X extends Throwable> ThrowingSupplier<T,X>	checked(Supplier<? extends T> supplier, Class<X> errorType)	Returns a supplier that calls the supplier supplier.
T	get()	Gets a result.
static <T,X extends Throwable> ThrowingSupplier<T,X>	of(ThrowingSupplier<T,X> supplier)	Factory method for turning ThrowingSupplier-shaped lambdas into ThrowingSuppliers.
default <E extends Throwable> ThrowingSupplier<T,E>	onErrorGetChecked(ThrowingSupplier<? extends T,? extends E> fallback)	Returns a supplier that calls this supplier.
default Supplier<T>	onErrorGetUnchecked(Supplier<? extends T> fallback)	Returns a supplier that calls this supplier.
default <E extends Throwable> ThrowingSupplier<T,E>	onErrorHandleChecked(ThrowingFunction<? super X,? extends T,? extends E> errorHandler)	Returns a supplier that calls this supplier.
default Supplier<T>	onErrorHandleUnchecked(Function<? super X,? extends T> errorHandler)	Returns a supplier that calls this supplier.
default Supplier<T>	onErrorReturn(T fallback)	Returns a supplier that calls this supplier.
default <E extends Throwable> ThrowingSupplier<T,E>	onErrorThrowAsChecked(Function<? super X,? extends E> errorMapper)	Returns a supplier that calls this supplier.
default <E extends RuntimeException> Supplier<T>	onErrorThrowAsUnchecked(Function<? super X,? extends E> errorMapper)	Returns a supplier that calls this supplier.
default Supplier<T>	unchecked()	Returns a supplier that applies this supplier to its input.
static <T> Supplier<T>	unchecked(ThrowingSupplier<? extends T,?> supplier)	Returns a supplier that calls the supplier supplier.

Method Detail

get

T get()
throws X extends Throwable

Gets a result.

Returns:

A result.

Throws:

X - If an error occurs.

X extends Throwable

onErrorThrowAsChecked

default <E extends Throwable> ThrowingSupplier<T,E> onErrorThrowAsChecked(Function<? super X,? extends E> errorMapper)

Returns a supplier that calls this supplier. Any checked exception thrown by this supplier is transformed using the given error mapper, and the returned supplier throws the transformation result.

Type Parameters:

E - The type of checked exception to transform to.

Parameters:

errorMapper - The function to use to transform any checked exception thrown by this supplier.

Returns:

A supplier that transforms any thrown checked exception.

Throws:

NullPointerException - If errorMapper is null.

onErrorThrowAsUnchecked

default <E extends RuntimeException> Supplier<T> onErrorThrowAsUnchecked(Function<? super X,? extends E> errorMapper)

Returns a supplier that calls this supplier. Any checked exception thrown by this supplier is transformed using the given error mapper, and the returned supplier throws the transformation result.

Type Parameters:

E - The type of unchecked exception to transform to.

Parameters:

errorMapper - The function to use to transform any checked exception thrown by this supplier.

Returns:

A supplier that transforms any thrown checked exception.

Throws:

NullPointerException - If errorMapper is null.

onErrorHandleChecked

default <E extends Throwable> ThrowingSupplier<T,E> onErrorHandleChecked(ThrowingFunction<? super X,? extends T,? extends E> errorHandler)

Returns a supplier that calls this supplier. Any checked exception thrown by this supplier is transformed using the given error handler, and the returned supplier returns the transformation result.

Type Parameters:

E - The type of checked exception that can be thrown by the given error handler.

Parameters:

errorHandler - The function to use to transform any checked exception thrown by this supplier.

Returns:

A supplier that transforms any thrown checked exception.

Throws:

NullPointerException - If errorHandler is null.

onErrorHandleUnchecked

default Supplier<T> onErrorHandleUnchecked(Function<? super X,? extends T> errorHandler)

Returns a supplier that calls this supplier. Any checked exception thrown by this supplier is transformed using the given error handler, and the returned supplier returns the transformation result.

Parameters:

errorHandler - The function to use to transform any checked exception thrown by this supplier.

Returns:

A supplier that transforms any thrown checked exception.

Throws:

NullPointerException - If errorHandler is null.

onErrorGetChecked

default <E extends Throwable> ThrowingSupplier<T,E> onErrorGetChecked(ThrowingSupplier<? extends T,? extends E> fallback)

Returns a supplier that calls this supplier. If this supplier throws any checked exception, it is discarded and the given fallback supplier is invoked.

Type Parameters:

E - The type of checked exception that can be thrown by the given fallback supplier.

Parameters:

fallback - The supplier to produce the value to return if this supplier throws any checked exception.

Returns:

A supplier that invokes the fallback supplier if this supplier throws any checked exception.

Throws:

NullPointerException - If fallback is null.

onErrorGetUnchecked

default Supplier<T> onErrorGetUnchecked(Supplier<? extends T> fallback)

Returns a supplier that calls this supplier. If this supplier throws any checked exception, it is discarded and the given fallback supplier is invoked.

Parameters:

fallback - The supplier to produce the value to return if this supplier throws any checked exception.

Returns:

A supplier that invokes the fallback supplier if this supplier throws any checked exception.

Throws:

NullPointerException - If fallback is null.

onErrorReturn

default Supplier<T> onErrorReturn(T fallback)

Returns a supplier that calls this supplier. If this supplier throws any checked exception, it is discarded and the given fallback value is returned.

Parameters:

fallback - The value to return if this supplier throws any checked exception.

Returns:

A supplier that returns the fallback value if this supplier throws any checked exception.

unchecked

default Supplier<T> unchecked()

Returns a supplier that applies this supplier to its input. Any checked exception thrown by this supplier is wrapped in an UncheckedException without a stack trace.

Returns:

A supplier that wraps any checked exception in an UncheckedException.

of

static <T,X extends Throwable> ThrowingSupplier<T,X> of(ThrowingSupplier<T,X> supplier)

Factory method for turning ThrowingSupplier-shaped lambdas into ThrowingSuppliers.

Type Parameters:

T - The type of the results supplied by the supplier.

X - The type of checked exception that can be thrown.

Parameters:

supplier - The lambda to return as ThrowingSupplier.

Returns:

The given lambda as a ThrowingSupplier.

Throws:

NullPointerException - If supplier is null.

unchecked

static <T> Supplier<T> unchecked(ThrowingSupplier<? extends T,?> supplier)

Returns a supplier that calls the supplier supplier. Any checked exception thrown by the supplier supplier is wrapped in an UncheckedException.

Type Parameters:

T - The type of the results supplied by the supplier.

Parameters:

supplier - The supplier to call when the returned supplier is invoked.

Returns:

A supplier that wraps any checked exception in an UncheckedException.

Throws:

NullPointerException - If function is null.

checked

static <T,X extends Throwable> ThrowingSupplier<T,X> checked(Supplier<? extends T> supplier)

Returns a supplier that calls the supplier supplier. Any unchecked exception thrown by the supplier supplier is relayed to the caller. This method allows existing Supplier instances to be used where ThrowingSupplier is expected.

Type Parameters:

T - The type of the results supplied by the supplier.

X - The type of checked exception that can be thrown.

Parameters:

supplier - The supplier to call when the returned function is invoked.

Returns:

A supplier that wraps any checked exception in an UncheckedException.

Throws:

NullPointerException - If supplier is null.

checked

static <T,X extends Throwable> ThrowingSupplier<T,X> checked(Supplier<? extends T> supplier,
                                                                         Class<X> errorType)

Returns a supplier that calls the supplier supplier. Any UncheckedException thrown by the supplier supplier is unwrapped if its cause is an instance of errorType, otherwise it is relayed to the caller.

Type Parameters:

T - The type of the results supplied by the supplier.

X - The type of checked exception that can be thrown.

Parameters:

supplier - The supplier to call when the returned supplier is invoked.

errorType - The type of checked exception that can be thrown.

Returns:

A supplier that wraps any checked exception in an UncheckedException.

Throws:

NullPointerException - If supplier or errorType is null.