com.github.fge.lambdas

Class Chainer<N,T extends N,C extends Chainer<N,T,C>>

java.lang.Object

com.github.fge.lambdas.Chainer<N,T,C>

Type Parameters:

N - parameter type of the non throwing interface

T - parameter type of the throwing interface

C - parameter type of the chainer

Direct Known Subclasses:

BiConsumerChainer, BiFunctionChainer, BinaryOperatorChainer, ComparatorChainer, ConsumerChainer, DoubleBinaryOperatorChainer, DoubleConsumerChainer, DoubleFunctionChainer, DoublePredicateChainer, DoubleSupplierChainer, DoubleToIntFunctionChainer, DoubleToLongFunctionChainer, DoubleUnaryOperatorChainer, FunctionChainer, IntBinaryOperatorChainer, IntConsumerChainer, IntFunctionChainer, IntPredicateChainer, IntSupplierChainer, IntToDoubleFunctionChainer, IntToLongFunctionChainer, IntUnaryOperatorChainer, LongBinaryOperatorChainer, LongConsumerChainer, LongFunctionChainer, LongPredicateChainer, LongSupplierChainer, LongToDoubleFunctionChainer, LongToIntFunctionChainer, LongUnaryOperatorChainer, ObjDoubleConsumerChainer, ObjIntConsumerChainer, ObjLongConsumerChainer, PredicateChainer, RunnableChainer, SupplierChainer, ToDoubleFunctionChainer, ToIntFunctionChainer, ToLongFunctionChainer, UnaryOperatorChainer

public abstract class Chainer<N,T extends N,C extends Chainer<N,T,C>>
extends Object

Base class for chaining throwing interfaces

If you want to add your own implementation of a chainer, extend this class and make it implement the throwing version of the interface. The default set by this package is to wrap the exception into a ThrownByLambdaException when an exception is thrown.

Since all throwing instances extend the non throwing instances by default, this means you can use an instance of a chain as a non throwing instance; for example:

     final ToLongFunction<Path>
         = Throwing.function(Files::size).orReturn(OL);
 

See Also:

Throwing

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	Chainer.InstantiationException Exception thrown when an instance of an exception class cannot be built

Field Summary

Fields

Modifier and Type	Field and Description
protected T	throwing

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	Chainer(T throwing)

Method Summary

Modifier and Type	Method and Description
protected static RuntimeException	doSneakyThrow(Throwable throwable)
abstract N	fallbackTo(N fallback) Fall back to a non throwing instance if this instance fails
abstract <E extends RuntimeException> T	orThrow(Class<E> exclass) Rethrow the exception using a custom (unchecked!) exception class if this throwing instance fails
abstract C	orTryWith(T other) Try with another throwing instance if the first instance fails
protected static <E extends RuntimeException> E	rethrow(Class<E> c, Throwable t)
abstract N	sneakyThrow() Sneaky throw of the exception thrown by the instance

Methods inherited from class java.lang.Object

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

Field Detail

throwing

protected final T extends N throwing

Constructor Detail

Chainer

protected Chainer(T throwing)

Method Detail

rethrow

protected static <E extends RuntimeException> E rethrow(Class<E> c,
                                                        Throwable t)

doSneakyThrow

protected static RuntimeException doSneakyThrow(Throwable throwable)

orTryWith

public abstract C orTryWith(T other)

Try with another throwing instance if the first instance fails

Parameters:

other - the other throwing instance

Returns:

a new chain

orThrow

public abstract <E extends RuntimeException> T orThrow(Class<E> exclass)

Rethrow the exception using a custom (unchecked!) exception class if this throwing instance fails

Your custom exception class must have a constructor accepting a single Throwable as an argument.

The original exception thrown will be the cause of the generated exception.

All instances of Error or RuntimeException thrown by the instance are thrown as is.

Type Parameters:

E - type parameter of the exception class

Parameters:

exclass - the exception class

Returns:

a throwing instance

fallbackTo

public abstract N fallbackTo(N fallback)

Fall back to a non throwing instance if this instance fails

Parameters:

fallback - the fallback instance

Returns:

a non throwing instance

sneakyThrow

public abstract N sneakyThrow()

Sneaky throw of the exception thrown by the instance

This code was inspited by the Lombok project.