Class Functions
java.util.function
package, or more
generally, with Java 8 lambdas. More specifically, it attempts to address the fact that lambdas are supposed not to
throw Exceptions, at least not checked Exceptions, AKA instances of Exception
. This enforces the use of
constructs like:
Consumer<java.lang.reflect.Method> consumer = m -> {
try {
m.invoke(o, args);
} catch (Throwable t) {
throw Functions.rethrow(t);
}
};
By replacing a Consumer<O>
with a FailableConsumer<O,? extends Throwable>
, this can be written like follows:
Functions.accept((m) -> m.invoke(o,args));
Obviously, the second version is much more concise and the spirit of Lambda expressions is met better than the second version.
- Since:
- 3.9
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Nested Class Summary
Modifier and TypeClassDescriptionstatic interface
Functions.FailableBiConsumer<O1,
O2, T extends Throwable> Deprecated.UseFailableBiConsumer
.static interface
Deprecated.UseFailableBiFunction
.static interface
Functions.FailableBiPredicate<O1,
O2, T extends Throwable> Deprecated.UseFailableBiPredicate
.static interface
Functions.FailableCallable<R,
T extends Throwable> Deprecated.UseFailableCallable
.static interface
Functions.FailableConsumer<O,
T extends Throwable> Deprecated.UseFailableConsumer
.static interface
Functions.FailableFunction<I,
R, T extends Throwable> Deprecated.UseFailableFunction
.static interface
Functions.FailablePredicate<I,
T extends Throwable> Deprecated.UseFailablePredicate
.static interface
Functions.FailableRunnable<T extends Throwable>
Deprecated.UseFailableRunnable
.static interface
Functions.FailableSupplier<R,
T extends Throwable> Deprecated.UseFailableSupplier
. -
Constructor Summary
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Method Summary
Modifier and TypeMethodDescriptionstatic <O1,
O2, T extends Throwable>
voidaccept
(Functions.FailableBiConsumer<O1, O2, T> consumer, O1 object1, O2 object2) Deprecated.Consumes a consumer and rethrows any exception as aRuntimeException
.static <O,
T extends Throwable>
voidaccept
(Functions.FailableConsumer<O, T> consumer, O object) Deprecated.Consumes a consumer and rethrows any exception as aRuntimeException
.static <O1,
O2, O, T extends Throwable>
Oapply
(Functions.FailableBiFunction<O1, O2, O, T> function, O1 input1, O2 input2) Deprecated.Applies a function and rethrows any exception as aRuntimeException
.static <I,
O, T extends Throwable>
Oapply
(Functions.FailableFunction<I, O, T> function, I input) Deprecated.Applies a function and rethrows any exception as aRuntimeException
.static <O1,
O2> BiConsumer<O1, O2> asBiConsumer
(Functions.FailableBiConsumer<O1, O2, ?> consumer) Deprecated.Converts the givenFunctions.FailableBiConsumer
into a standardBiConsumer
.static <O1,
O2, O> BiFunction<O1, O2, O> asBiFunction
(Functions.FailableBiFunction<O1, O2, O, ?> function) Deprecated.Converts the givenFunctions.FailableBiFunction
into a standardBiFunction
.static <O1,
O2> BiPredicate<O1, O2> asBiPredicate
(Functions.FailableBiPredicate<O1, O2, ?> predicate) Deprecated.Converts the givenFunctions.FailableBiPredicate
into a standardBiPredicate
.static <O> Callable<O>
asCallable
(Functions.FailableCallable<O, ?> callable) Deprecated.Converts the givenFunctions.FailableCallable
into a standardCallable
.static <I> Consumer<I>
asConsumer
(Functions.FailableConsumer<I, ?> consumer) Deprecated.Converts the givenFunctions.FailableConsumer
into a standardConsumer
.static <I,
O> Function<I, O> asFunction
(Functions.FailableFunction<I, O, ?> function) Deprecated.Converts the givenFunctions.FailableFunction
into a standardFunction
.static <I> Predicate<I>
asPredicate
(Functions.FailablePredicate<I, ?> predicate) Deprecated.Converts the givenFunctions.FailablePredicate
into a standardPredicate
.static Runnable
asRunnable
(Functions.FailableRunnable<?> runnable) Deprecated.Converts the givenFunctions.FailableRunnable
into a standardRunnable
.static <O> Supplier<O>
asSupplier
(Functions.FailableSupplier<O, ?> supplier) Deprecated.Converts the givenFunctions.FailableSupplier
into a standardSupplier
.static <O,
T extends Throwable>
Ocall
(Functions.FailableCallable<O, T> callable) Deprecated.Calls a callable and rethrows any exception as aRuntimeException
.static <O,
T extends Throwable>
Oget
(Functions.FailableSupplier<O, T> supplier) Deprecated.Invokes a supplier, and returns the result.static RuntimeException
Deprecated.Rethrows aThrowable
as an unchecked exception.static <T extends Throwable>
voidrun
(Functions.FailableRunnable<T> runnable) Deprecated.Runs a runnable and rethrows any exception as aRuntimeException
.static <O> Streams.FailableStream<O>
stream
(Collection<O> collection) Deprecated.Converts the given collection into aStreams.FailableStream
.static <O> Streams.FailableStream<O>
Deprecated.Converts the given stream into aStreams.FailableStream
.static <O1,
O2, T extends Throwable>
booleantest
(Functions.FailableBiPredicate<O1, O2, T> predicate, O1 object1, O2 object2) Deprecated.Tests a predicate and rethrows any exception as aRuntimeException
.static <O,
T extends Throwable>
booleantest
(Functions.FailablePredicate<O, T> predicate, O object) Deprecated.Tests a predicate and rethrows any exception as aRuntimeException
.static void
tryWithResources
(Functions.FailableRunnable<? extends Throwable> action, Functions.FailableConsumer<Throwable, ? extends Throwable> errorHandler, Functions.FailableRunnable<? extends Throwable>... resources) Deprecated.A simple try-with-resources implementation, that can be used, if your objects do not implement theAutoCloseable
interface.static void
tryWithResources
(Functions.FailableRunnable<? extends Throwable> action, Functions.FailableRunnable<? extends Throwable>... resources) Deprecated.A simple try-with-resources implementation, that can be used, if your objects do not implement theAutoCloseable
interface.
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Constructor Details
-
Functions
public Functions()Deprecated.
-
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Method Details
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accept
public static <O1,O2, void acceptT extends Throwable> (Functions.FailableBiConsumer<O1, O2, T> consumer, O1 object1, O2 object2) Deprecated.Consumes a consumer and rethrows any exception as aRuntimeException
.- Type Parameters:
O1
- the type of the first argument the consumer acceptsO2
- the type of the second argument the consumer acceptsT
- the type of checked exception the consumer may throw- Parameters:
consumer
- the consumer to consumeobject1
- the first object to consume byconsumer
object2
- the second object to consume byconsumer
-
accept
public static <O,T extends Throwable> void accept(Functions.FailableConsumer<O, T> consumer, O object) Deprecated.Consumes a consumer and rethrows any exception as aRuntimeException
.- Type Parameters:
O
- the type the consumer acceptsT
- the type of checked exception the consumer may throw- Parameters:
consumer
- the consumer to consumeobject
- the object to consume byconsumer
-
apply
public static <O1,O2, O applyO, T extends Throwable> (Functions.FailableBiFunction<O1, O2, O, T> function, O1 input1, O2 input2) Deprecated.Applies a function and rethrows any exception as aRuntimeException
.- Type Parameters:
O1
- the type of the first argument the function acceptsO2
- the type of the second argument the function acceptsO
- the return type of the functionT
- the type of checked exception the function may throw- Parameters:
function
- the function to applyinput1
- the first input to applyfunction
oninput2
- the second input to applyfunction
on- Returns:
- the value returned from the function
-
apply
public static <I,O, O applyT extends Throwable> (Functions.FailableFunction<I, O, T> function, I input) Deprecated.Applies a function and rethrows any exception as aRuntimeException
.- Type Parameters:
I
- the type of the argument the function acceptsO
- the return type of the functionT
- the type of checked exception the function may throw- Parameters:
function
- the function to applyinput
- the input to applyfunction
on- Returns:
- the value returned from the function
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asBiConsumer
public static <O1,O2> BiConsumer<O1,O2> asBiConsumer(Functions.FailableBiConsumer<O1, O2, ?> consumer) Deprecated.Converts the givenFunctions.FailableBiConsumer
into a standardBiConsumer
.- Type Parameters:
O1
- the type of the first argument of the consumersO2
- the type of the second argument of the consumers- Parameters:
consumer
- a failableBiConsumer
- Returns:
- a standard
BiConsumer
- Since:
- 3.10
-
asBiFunction
public static <O1,O2, BiFunction<O1,O> O2, asBiFunctionO> (Functions.FailableBiFunction<O1, O2, O, ?> function) Deprecated.Converts the givenFunctions.FailableBiFunction
into a standardBiFunction
.- Type Parameters:
O1
- the type of the first argument of the input of the functionsO2
- the type of the second argument of the input of the functionsO
- the type of the output of the functions- Parameters:
function
- aFailableBiFunction
- Returns:
- a standard
BiFunction
- Since:
- 3.10
-
asBiPredicate
public static <O1,O2> BiPredicate<O1,O2> asBiPredicate(Functions.FailableBiPredicate<O1, O2, ?> predicate) Deprecated.Converts the givenFunctions.FailableBiPredicate
into a standardBiPredicate
.- Type Parameters:
O1
- the type of the first argument used by the predicatesO2
- the type of the second argument used by the predicates- Parameters:
predicate
- aFailableBiPredicate
- Returns:
- a standard
BiPredicate
- Since:
- 3.10
-
asCallable
Deprecated.Converts the givenFunctions.FailableCallable
into a standardCallable
.- Type Parameters:
O
- the type used by the callables- Parameters:
callable
- aFailableCallable
- Returns:
- a standard
Callable
- Since:
- 3.10
-
asConsumer
Deprecated.Converts the givenFunctions.FailableConsumer
into a standardConsumer
.- Type Parameters:
I
- the type used by the consumers- Parameters:
consumer
- aFailableConsumer
- Returns:
- a standard
Consumer
- Since:
- 3.10
-
asFunction
Deprecated.Converts the givenFunctions.FailableFunction
into a standardFunction
.- Type Parameters:
I
- the type of the input of the functionsO
- the type of the output of the functions- Parameters:
function
- a {code FailableFunction}- Returns:
- a standard
Function
- Since:
- 3.10
-
asPredicate
Deprecated.Converts the givenFunctions.FailablePredicate
into a standardPredicate
.- Type Parameters:
I
- the type used by the predicates- Parameters:
predicate
- aFailablePredicate
- Returns:
- a standard
Predicate
- Since:
- 3.10
-
asRunnable
Deprecated.Converts the givenFunctions.FailableRunnable
into a standardRunnable
.- Parameters:
runnable
- aFailableRunnable
- Returns:
- a standard
Runnable
- Since:
- 3.10
-
asSupplier
Deprecated.Converts the givenFunctions.FailableSupplier
into a standardSupplier
.- Type Parameters:
O
- the type supplied by the suppliers- Parameters:
supplier
- aFailableSupplier
- Returns:
- a standard
Supplier
- Since:
- 3.10
-
call
Deprecated.Calls a callable and rethrows any exception as aRuntimeException
.- Type Parameters:
O
- the return type of the callableT
- the type of checked exception the callable may throw- Parameters:
callable
- the callable to call- Returns:
- the value returned from the callable
-
get
Deprecated.Invokes a supplier, and returns the result.- Type Parameters:
O
- The suppliers output type.T
- The type of checked exception, which the supplier can throw.- Parameters:
supplier
- The supplier to invoke.- Returns:
- The object, which has been created by the supplier
- Since:
- 3.10
-
rethrow
Deprecated.Rethrows a
Throwable
as an unchecked exception. If the argument is already unchecked, namely aRuntimeException
orError
then the argument will be rethrown without modification. If the exception isIOException
then it will be wrapped into aUncheckedIOException
. In every other cases the exception will be wrapped into aUndeclaredThrowableException
Note that there is a declared return type for this method, even though it never returns. The reason for that is to support the usual pattern:
throw rethrow(myUncheckedException);
instead of just calling the method. This pattern may help the Java compiler to recognize that at that point an exception will be thrown and the code flow analysis will not demand otherwise mandatory commands that could follow the method call, like a
return
statement from a value returning method.- Parameters:
throwable
- The throwable to rethrow ossibly wrapped into an unchecked exception- Returns:
- Never returns anything, this method never terminates normally.
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run
Deprecated.Runs a runnable and rethrows any exception as aRuntimeException
.- Type Parameters:
T
- the type of checked exception the runnable may throw- Parameters:
runnable
- The runnable to run
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stream
Deprecated.Converts the given collection into aStreams.FailableStream
. TheStreams.FailableStream
consists of the collections elements. Shortcut forFunctions.stream(collection.stream());
- Type Parameters:
O
- The collections element type. (In turn, the result streams element type.)- Parameters:
collection
- The collection, which is being converted into aStreams.FailableStream
.- Returns:
- The created
Streams.FailableStream
. - Since:
- 3.10
-
stream
Deprecated.Converts the given stream into aStreams.FailableStream
. TheStreams.FailableStream
consists of the same elements, than the input stream. However, failable lambdas, likeFunctions.FailablePredicate
,Functions.FailableFunction
, andFunctions.FailableConsumer
may be applied, rather thanPredicate
,Function
,Consumer
, etc.- Type Parameters:
O
- The streams element type.- Parameters:
stream
- The stream, which is being converted into aStreams.FailableStream
.- Returns:
- The created
Streams.FailableStream
. - Since:
- 3.10
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test
public static <O1,O2, boolean testT extends Throwable> (Functions.FailableBiPredicate<O1, O2, T> predicate, O1 object1, O2 object2) Deprecated.Tests a predicate and rethrows any exception as aRuntimeException
.- Type Parameters:
O1
- the type of the first argument the predicate testsO2
- the type of the second argument the predicate testsT
- the type of checked exception the predicate may throw- Parameters:
predicate
- the predicate to testobject1
- the first input to test bypredicate
object2
- the second input to test bypredicate
- Returns:
- the boolean value returned by the predicate
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test
public static <O,T extends Throwable> boolean test(Functions.FailablePredicate<O, T> predicate, O object) Deprecated.Tests a predicate and rethrows any exception as aRuntimeException
.- Type Parameters:
O
- the type of argument the predicate testsT
- the type of checked exception the predicate may throw- Parameters:
predicate
- the predicate to testobject
- the input to test bypredicate
- Returns:
- the boolean value returned by the predicate
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tryWithResources
@SafeVarargs public static void tryWithResources(Functions.FailableRunnable<? extends Throwable> action, Functions.FailableConsumer<Throwable, ? extends Throwable> errorHandler, Functions.FailableRunnable<? extends Throwable>... resources) Deprecated.A simple try-with-resources implementation, that can be used, if your objects do not implement theAutoCloseable
interface. The method executes theaction
. The method guarantees, that all theresources
are being executed, in the given order, afterwards, and regardless of success, or failure. If either the original action, or any of the resource action fails, then the first failure (AKAThrowable
is rethrown. Example use:final FileInputStream fis = new FileInputStream("my.file"); Functions.tryWithResources(useInputStream(fis), null, () -> fis.close());
- Parameters:
action
- The action to execute. This object will always be invoked.errorHandler
- An optional error handler, which will be invoked finally, if any error occurred. The error handler will receive the first error, AKAThrowable
.resources
- The resource actions to execute. All resource actions will be invoked, in the given order. A resource action is an instance ofFunctions.FailableRunnable
, which will be executed.- See Also:
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tryWithResources
@SafeVarargs public static void tryWithResources(Functions.FailableRunnable<? extends Throwable> action, Functions.FailableRunnable<? extends Throwable>... resources) Deprecated.A simple try-with-resources implementation, that can be used, if your objects do not implement theAutoCloseable
interface. The method executes theaction
. The method guarantees, that all theresources
are being executed, in the given order, afterwards, and regardless of success, or failure. If either the original action, or any of the resource action fails, then the first failure (AKAThrowable
is rethrown. Example use:final FileInputStream fis = new FileInputStream("my.file"); Functions.tryWithResources(useInputStream(fis), () -> fis.close());
- Parameters:
action
- The action to execute. This object will always be invoked.resources
- The resource actions to execute. All resource actions will be invoked, in the given order. A resource action is an instance ofFunctions.FailableRunnable
, which will be executed.- See Also:
-
Failable
.