This is an automated email from the ASF dual-hosted git repository.
jochen pushed a commit to branch master
in repository https://gitbox.apache.org/repos/asf/commons-lang.git
The following commit(s) were added to refs/heads/master by this push:
new 2ea44b2 - Added the Streams class. - Added Functions.stream() as an
accessor method.
2ea44b2 is described below
commit 2ea44b2adae8da8e3e7f55cc226479f9431feda9
Author: Jochen Wiedmann <jochen.wiedm...@gmail.com>
AuthorDate: Sun Jan 26 22:57:13 2020 +0100
- Added the Streams class.
- Added Functions.stream() as an accessor method.
---
src/changes/changes.xml | 1 +
.../java/org/apache/commons/lang3/Functions.java | 37 ++
.../java/org/apache/commons/lang3/Streams.java | 380 +++++++++++++++++++++
.../java/org/apache/commons/lang3/StreamsTest.java | 176 ++++++++++
4 files changed, 594 insertions(+)
diff --git a/src/changes/changes.xml b/src/changes/changes.xml
index 11f89c4..c5516d5 100644
--- a/src/changes/changes.xml
+++ b/src/changes/changes.xml
@@ -95,6 +95,7 @@ The <action> type attribute can be add,update,fix,remove.
<action issue="LANG-1510" type="add" dev="ggregory" due-to="Gary
Gregory">Add org.apache.commons.lang3.arch.Processor.Arch.getLabel().</action>
<action issue="LANG-1512" type="add" dev="ggregory" due-to="Gary
Gregory">Add IS_JAVA_14 and IS_JAVA_15 to
org.apache.commons.lang3.SystemUtils.</action>
<action issue="LANG-1513" type="add" dev="ggregory" due-to="Bernhard
Bonigl, Gary Gregory">ObjectUtils: Get first non-null supplier value.</action>
+ <action type="add" dev="jochen">Added the Streams class,
and Functions.stream() as an accessor thereof.</action>
</release>
<release version="3.9" date="2019-04-09" description="New features and bug
fixes. Requires Java 8, supports Java 9, 10, 11.">
diff --git a/src/main/java/org/apache/commons/lang3/Functions.java
b/src/main/java/org/apache/commons/lang3/Functions.java
index 2d0ca06..ef9c45d 100644
--- a/src/main/java/org/apache/commons/lang3/Functions.java
+++ b/src/main/java/org/apache/commons/lang3/Functions.java
@@ -19,6 +19,7 @@ package org.apache.commons.lang3;
import java.io.IOException;
import java.io.UncheckedIOException;
import java.lang.reflect.UndeclaredThrowableException;
+import java.util.Collection;
import java.util.Objects;
import java.util.concurrent.Callable;
import java.util.function.BiConsumer;
@@ -28,6 +29,9 @@ import java.util.function.Consumer;
import java.util.function.Function;
import java.util.function.Predicate;
import java.util.function.Supplier;
+import java.util.stream.Stream;
+
+import org.apache.commons.lang3.Streams.FailableStream;
/** This class provides utility functions, and classes for working with the
@@ -400,6 +404,39 @@ public class Functions {
}
}
+ /**
+ * Converts the given stream into a {@link FailableStream}. The
+ * {@link FailableStream} consists of the same elements, than the
+ * input stream. However, failable lambdas, like
+ * {@link FailablePredicate}, {@link FailableFunction}, and
+ * {@link FailableConsumer} may be applied, rather than
+ * {@link Predicate}, {@link Function}, {@link Consumer}, etc.
+ * @param pStream The stream, which is being converted into a
+ * {@link FailableStream}.
+ * @param <O> The streams element type.
+ * @return The created {@link FailableStream}.
+ */
+ public static <O> FailableStream<O> stream(Stream<O> pStream) {
+ return new FailableStream<O>(pStream);
+ }
+
+ /**
+ * Converts the given collection into a {@link FailableStream}.
+ * The {@link FailableStream} consists of the collections
+ * elements. Shortcut for
+ * <pre>
+ * Functions.stream(pCollection.stream());
+ * </pre>
+ * @param pCollection The collection, which is being converted into a
+ * {@link FailableStream}.
+ * @param <O> The collections element type. (In turn, the result
+ * streams element type.)
+ * @return The created {@link FailableStream}.
+ */
+ public static <O> FailableStream<O> stream(Collection<O> pCollection) {
+ return new FailableStream<O>(pCollection.stream());
+ }
+
/**
* A simple try-with-resources implementation, that can be used, if your
diff --git a/src/main/java/org/apache/commons/lang3/Streams.java
b/src/main/java/org/apache/commons/lang3/Streams.java
new file mode 100644
index 0000000..a0f32af
--- /dev/null
+++ b/src/main/java/org/apache/commons/lang3/Streams.java
@@ -0,0 +1,380 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.commons.lang3;
+
+import java.util.function.BiConsumer;
+import java.util.function.BinaryOperator;
+import java.util.function.Consumer;
+import java.util.function.Function;
+import java.util.function.Predicate;
+import java.util.function.Supplier;
+import java.util.stream.Collector;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
+
+import org.apache.commons.lang3.Functions.FailableConsumer;
+import org.apache.commons.lang3.Functions.FailableFunction;
+import org.apache.commons.lang3.Functions.FailablePredicate;
+
+/**
+ * This class provides utility functions, and classes for working with the
+ * java.util.stream 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 {@link Exception}. This enforces the use of constructs like
+ * <pre>
+ * Consumer<java.lang.reflect.Method> consumer = (m) -> {
+ * try {
+ * m.invoke(o, args);
+ * } catch (Throwable t) {
+ * throw Functions.rethrow(t);
+ * }
+ * };
+ * stream.forEach(consumer);
+ * </pre>
+ * Using a {@link FailableStream}, this can be rewritten as follows:
+ * <pre>
+ * ObjectStreams.failable(stream).forEach((m) -> m.invoke(o, args));
+ * </pre>
+ * Obviously, the second version is much more concise and the spirit of
+ * Lambda expressions is met better than in the first version.
+ * @see Stream
+ * @see Functions
+ */
+public class Streams {
+ /** A reduced, and simplified version of a {@link Stream} with
+ * failable method signatures.
+ * @param <O> The streams element type.
+ */
+ public static class FailableStream<O extends Object> {
+ private Stream<O> stream;
+ private boolean terminated;
+
+ public FailableStream(Stream<O> pStream) {
+ stream = pStream;
+ }
+
+ protected void assertNotTerminated() {
+ if (terminated) {
+ throw new IllegalStateException("This stream is already
terminated.");
+ }
+ }
+
+ protected void makeTerminated() {
+ assertNotTerminated();
+ terminated = true;
+ }
+
+ /**
+ * Returns a FailableStream consisting of the elements of this
stream that match
+ * the given FailablePredicate.
+ *
+ * <p>This is an intermediate operation.
+ *
+ * @param pPredicate a non-interfering, stateless predicate to
apply to each
+ * element to determine if it should be included.
+ * @return the new stream
+ */
+ public FailableStream<O> filter(FailablePredicate<O,?>
pPredicate){
+ assertNotTerminated();
+ stream =
stream.filter(Functions.asPredicate(pPredicate));
+ return this;
+ }
+
+ /**
+ * Performs an action for each element of this stream.
+ *
+ * <p>This is a terminal operation.
+ *
+ * <p>The behavior of this operation is explicitly nondeterministic.
+ * For parallel stream pipelines, this operation does <em>not</em>
+ * guarantee to respect the encounter order of the stream, as doing
so
+ * would sacrifice the benefit of parallelism. For any given
element, the
+ * action may be performed at whatever time and in whatever thread
the
+ * library chooses. If the action accesses shared state, it is
+ * responsible for providing the required synchronization.
+ *
+ * @param pAction a non-interfering action to perform on the
elements
+ */
+ public void forEach(FailableConsumer<O,?> pAction) {
+ makeTerminated();
+ stream().forEach(Functions.asConsumer(pAction));
+ }
+
+ /**
+ * Performs a mutable reduction operation on the elements of this
stream using a
+ * {@code Collector}. A {@code Collector}
+ * encapsulates the functions used as arguments to
+ * {@link #collect(Supplier, BiConsumer, BiConsumer)}, allowing for
reuse of
+ * collection strategies and composition of collect operations such
as
+ * multiple-level grouping or partitioning.
+ *
+ * <p>If the underlying stream is parallel, and the {@code
Collector}
+ * is concurrent, and either the stream is unordered or the
collector is
+ * unordered, then a concurrent reduction will be performed
+ * (see {@link Collector} for details on concurrent reduction.)
+ *
+ * <p>This is a terminal operation.
+ *
+ * <p>When executed in parallel, multiple intermediate results may
be
+ * instantiated, populated, and merged so as to maintain isolation
of
+ * mutable data structures. Therefore, even when executed in
parallel
+ * with non-thread-safe data structures (such as {@code
ArrayList}), no
+ * additional synchronization is needed for a parallel reduction.
+ *
+ * \@apiNote
+ * The following will accumulate strings into an ArrayList:
+ * <pre>{@code
+ * List<String> asList =
stringStream.collect(Collectors.toList());
+ * }</pre>
+ *
+ * <p>The following will classify {@code Person} objects by city:
+ * <pre>{@code
+ * Map<String, List<Person>> peopleByCity
+ * =
personStream.collect(Collectors.groupingBy(Person::getCity));
+ * }</pre>
+ *
+ * <p>The following will classify {@code Person} objects by state
and city,
+ * cascading two {@code Collector}s together:
+ * <pre>{@code
+ * Map<String, Map<String, List<Person>>> peopleByStateAndCity
+ * =
personStream.collect(Collectors.groupingBy(Person::getState,
+ *
Collectors.groupingBy(Person::getCity)));
+ * }</pre>
+ *
+ * @param <R> the type of the result
+ * @param <A> the intermediate accumulation type of the {@code
Collector}
+ * @param pCollector the {@code Collector} describing the reduction
+ * @return the result of the reduction
+ * @see #collect(Supplier, BiConsumer, BiConsumer)
+ * @see Collectors
+ */
+ public <A,R> R collect(Collector<? super O,A,R> pCollector) {
+ makeTerminated();
+ return stream().collect(pCollector);
+ }
+
+ /**
+ * Performs a mutable reduction operation on the elements of this
FailableStream.
+ * A mutable reduction is one in which the reduced value is a
mutable result
+ * container, such as an {@code ArrayList}, and elements are
incorporated by updating
+ * the state of the result rather than by replacing the result.
This produces a result equivalent to:
+ * <pre>{@code
+ * R result = supplier.get();
+ * for (T element : this stream)
+ * accumulator.accept(result, element);
+ * return result;
+ * }</pre>
+ *
+ * <p>Like {@link #reduce(Object, BinaryOperator)}, {@code collect}
operations
+ * can be parallelized without requiring additional synchronization.
+ *
+ * <p>This is a terminal operation.
+ *
+ * \@apiNote There are many existing classes in the JDK whose
signatures are
+ * well-suited for use with method references as arguments to
{@code collect()}.
+ * For example, the following will accumulate strings into an
{@code ArrayList}:
+ * <pre>{@code
+ * List<String> asList = stringStream.collect(ArrayList::new,
ArrayList::add,
+ *
ArrayList::addAll);
+ * }</pre>
+ *
+ * <p>The following will take a stream of strings and concatenates
them into a
+ * single string:
+ * <pre>{@code
+ * String concat = stringStream.collect(StringBuilder::new,
StringBuilder::append,
+ * StringBuilder::append)
+ * .toString();
+ * }</pre>
+ *
+ * @param <R> type of the result
+ * @param <A> Type of the accumulator.
+ * @param pSupplier a function that creates a new result container.
For a
+ * parallel execution, this function may be called
+ * multiple times and must return a fresh value
each time.
+ * @param pAccumulator An associative, non-interfering, stateless
function for
+ * incorporating an additional element into a result
+ * @param pCombiner An associative, non-interfering, stateless
+ * function for combining two values, which must be compatible
with the
+ * accumulator function
+ * @return The result of the reduction
+ */
+ public <A,R> R collect(Supplier<R> pSupplier, BiConsumer<R,?
super O> pAccumulator, BiConsumer<R,R> pCombiner) {
+ makeTerminated();
+ return stream().collect(pSupplier, pAccumulator,
pCombiner);
+ }
+
+ /**
+ * Performs a reduction on the elements of this stream, using the
provided
+ * identity value and an associative accumulation function, and
returns
+ * the reduced value. This is equivalent to:
+ * <pre>{@code
+ * T result = identity;
+ * for (T element : this stream)
+ * result = accumulator.apply(result, element)
+ * return result;
+ * }</pre>
+ *
+ * but is not constrained to execute sequentially.
+ *
+ * <p>The {@code identity} value must be an identity for the
accumulator
+ * function. This means that for all {@code t},
+ * {@code accumulator.apply(identity, t)} is equal to {@code t}.
+ * The {@code accumulator} function must be an associative function.
+ *
+ * <p>This is a terminal operation.
+ *
+ * \@apiNote Sum, min, max, average, and string concatenation are
all special
+ * cases of reduction. Summing a stream of numbers can be expressed
as:
+ *
+ * <pre>{@code
+ * Integer sum = integers.reduce(0, (a, b) -> a+b);
+ * }</pre>
+ *
+ * or:
+ *
+ * <pre>{@code
+ * Integer sum = integers.reduce(0, Integer::sum);
+ * }</pre>
+ *
+ * <p>While this may seem a more roundabout way to perform an
aggregation
+ * compared to simply mutating a running total in a loop, reduction
+ * operations parallelize more gracefully, without needing
additional
+ * synchronization and with greatly reduced risk of data races.
+ *
+ * @param pIdentity the identity value for the accumulating function
+ * @param pAccumulator an associative, non-interfering, stateless
+ * function for combining two values
+ * @return the result of the reduction
+ */
+ public O reduce(O pIdentity, BinaryOperator<O> pAccumulator) {
+ makeTerminated();
+ return stream().reduce(pIdentity, pAccumulator);
+ }
+
+ /**
+ * Returns a stream consisting of the results of applying the given
+ * function to the elements of this stream.
+ *
+ * <p>This is an intermediate operation.
+ *
+ * @param <R> The element type of the new stream
+ * @param pMapper A non-interfering, stateless function to apply to
each element
+ * @return the new stream
+ */
+ public <R> FailableStream<R> map(FailableFunction<O,R,?>
pMapper) {
+ assertNotTerminated();
+ return new
FailableStream<R>(stream.map(Functions.asFunction(pMapper)));
+ }
+
+ /**
+ * Converts the FailableStream into an equivalent stream.
+ * @return A stream, which will return the same elements, which
this FailableStream would return.
+ */
+ public Stream<O> stream() {
+ return stream;
+ }
+
+ /**
+ * Returns whether all elements of this stream match the provided
predicate.
+ * May not evaluate the predicate on all elements if not necessary
for
+ * determining the result. If the stream is empty then {@code
true} is
+ * returned and the predicate is not evaluated.
+ *
+ * <p>This is a short-circuiting terminal operation.
+ *
+ * \@apiNote
+ * This method evaluates the <em>universal quantification</em> of
the
+ * predicate over the elements of the stream (for all x P(x)). If
the
+ * stream is empty, the quantification is said to be <em>vacuously
+ * satisfied</em> and is always {@code true} (regardless of P(x)).
+ *
+ * @param pPredicate A non-interfering, stateless predicate to
apply to
+ * elements of this stream
+ * @return {@code true} If either all elements of the stream match
the
+ * provided predicate or the stream is empty, otherwise {@code
false}.
+ */
+ public boolean allMatch(FailablePredicate<O,?> pPredicate) {
+ assertNotTerminated();
+ return
stream().allMatch(Functions.asPredicate(pPredicate));
+ }
+
+ /**
+ * Returns whether any elements of this stream match the provided
+ * predicate. May not evaluate the predicate on all elements if not
+ * necessary for determining the result. If the stream is empty
then
+ * {@code false} is returned and the predicate is not evaluated.
+ *
+ * <p>This is a short-circuiting terminal operation.
+ *
+ * \@apiNote
+ * This method evaluates the <em>existential quantification</em> of
the
+ * predicate over the elements of the stream (for some x P(x)).
+ *
+ * @param pPredicate A non-interfering, stateless predicate to
apply to
+ * elements of this stream
+ * @return {@code true} if any elements of the stream match the
provided
+ * predicate, otherwise {@code false}
+ */
+ public boolean anyMatch(FailablePredicate<O,?> pPredicate) {
+ assertNotTerminated();
+ return stream().anyMatch(Functions.asPredicate(pPredicate));
+ }
+ }
+
+ /**
+ * Converts the given {@link Stream stream} into a {@link
FailableStream}.
+ * This is basically a simplified, reduced version of the {@link Stream}
+ * class, with the same underlying element stream, except that failable
+ * objects, like {@link FailablePredicate}, {@link FailableFunction}, or
+ * {@link FailableConsumer} may be applied, instead of
+ * {@link Predicate}, {@link Function}, or {@link Consumer}. The idea is
+ * to rewrite a code snippet like this:
+ * <pre>
+ * final List<O> list;
+ * final Method m;
+ * final Function<O,String> mapper = (o) -> {
+ * try {
+ * return (String) m.invoke(o);
+ * } catch (Throwable t) {
+ * throw Functions.rethrow(t);
+ * }
+ * };
+ * final List<String> strList = list.stream()
+ * .map(mapper).collect(Collectors.toList());
+ * </pre>
+ * as follows:
+ * <pre>
+ * final List<O> list;
+ * final Method m;
+ * final List<String> strList = Functions.stream(list.stream())
+ * .map((o) -> (String)
m.invoke(o)).collect(Collectors.toList());
+ * </pre>
+ * While the second version may not be <em>quite</em> as
+ * efficient (because it depends on the creation of additional,
+ * intermediate objects, of type FailableStream), it is much more
+ * concise, and readable, and meets the spirit of Lambdas better
+ * than the first version.
+ * @param <O> The streams element type.
+ * @param pStream The stream, which is being converted.
+ * @return The {@link FailableStream}, which has been created by
+ * converting the stream.
+ */
+ public static <O> FailableStream<O> stream(Stream<O> pStream) {
+ return new FailableStream<O>(pStream);
+ }
+}
diff --git a/src/test/java/org/apache/commons/lang3/StreamsTest.java
b/src/test/java/org/apache/commons/lang3/StreamsTest.java
new file mode 100644
index 0000000..9ad8e78
--- /dev/null
+++ b/src/test/java/org/apache/commons/lang3/StreamsTest.java
@@ -0,0 +1,176 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.commons.lang3;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+import java.lang.reflect.UndeclaredThrowableException;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+import java.util.stream.Collectors;
+
+import org.apache.commons.lang3.Functions.FailableConsumer;
+import org.apache.commons.lang3.Functions.FailablePredicate;
+import org.junit.jupiter.api.Test;
+import org.xml.sax.SAXException;
+
+class StreamsTest {
+ @Test
+ void testSimpleStreamMap() {
+ final List<String> input = Arrays.asList("1", "2", "3", "4", "5", "6");
+ final List<Integer> output = Functions.stream(input).map((s) ->
Integer.valueOf(s)).collect(Collectors.toList());
+ assertEquals(6, output.size());
+ for (int i = 0; i < 6; i++) {
+ assertEquals(i+1, output.get(i).intValue());
+ }
+ }
+
+ @Test
+ void testSimpleStreamMapFailing() {
+ final List<String> input = Arrays.asList("1", "2", "3", "4 ", "5",
"6");
+ try {
+ Functions.stream(input).map((s) ->
Integer.valueOf(s)).collect(Collectors.toList());
+ fail("Expected Exception");
+ } catch (NumberFormatException nfe) {
+ assertEquals("For input string: \"4 \"", nfe.getMessage());
+ }
+ }
+
+ @Test
+ void testSimpleStreamForEach() {
+ final List<String> input = Arrays.asList("1", "2", "3", "4", "5", "6");
+ final List<Integer> output = new ArrayList<>();
+ Functions.stream(input).forEach((s) -> output.add(Integer.valueOf(s)));
+ assertEquals(6, output.size());
+ for (int i = 0; i < 6; i++) {
+ assertEquals(i+1, output.get(i).intValue());
+ }
+ }
+
+ protected <T extends Throwable> FailableConsumer<String,T> asIntConsumer(T
pThrowable) {
+ return (s) -> {
+ final Integer i = Integer.valueOf(s);
+ if (i.intValue() == 4) {
+ throw pThrowable;
+ }
+ };
+ }
+
+ @Test
+ void testSimpleStreamForEachFailing() {
+ final List<String> input = Arrays.asList("1", "2", "3", "4", "5", "6");
+ final List<Integer> output = new ArrayList<>();
+ final IllegalArgumentException ise = new
IllegalArgumentException("Invalid argument: 4");
+ try {
+ Functions.stream(input).forEach(asIntConsumer(ise));
+ fail("Expected Exception");
+ } catch (IllegalArgumentException e) {
+ assertSame(ise, e);
+ }
+ output.clear();
+ final OutOfMemoryError oome = new OutOfMemoryError();
+ try {
+ Functions.stream(input).forEach(asIntConsumer(oome));
+ fail("Expected Exception");
+ } catch (Throwable t) {
+ assertSame(oome, t);
+ }
+ output.clear();
+ final SAXException se = new SAXException();
+ try {
+ Functions.stream(input).forEach(asIntConsumer(se));
+ fail("Expected Exception");
+ } catch (UndeclaredThrowableException ute) {
+ assertSame(se, ute.getCause());
+ }
+ }
+
+ @Test
+ void testSimpleStreamFilter() {
+ final List<String> input = Arrays.asList("1", "2", "3", "4", "5", "6");
+ final List<Integer> output = Functions.stream(input)
+ .map((s) -> Integer.valueOf(s))
+ .filter((i) -> { return i.intValue() %2 == 0;})
+ .collect(Collectors.toList());
+ assertEvenNumbers(output);
+ }
+
+ private void assertEvenNumbers(final List<Integer> output) {
+ assertEquals(3, output.size());
+ for (int i = 0; i < 3; i++) {
+ assertEquals((i+1)*2, output.get(i).intValue());
+ }
+ }
+
+ protected <T extends Throwable> FailablePredicate<Integer,T>
asIntPredicate(T pThrowable) {
+ return (i) -> {
+ if (i.intValue() == 5) {
+ if (pThrowable != null) {
+ throw pThrowable;
+ }
+ }
+ return i%2==0;
+ };
+ }
+
+ @Test
+ void testSimpleStreamFilterFailing() {
+ final List<String> input = Arrays.asList("1", "2", "3", "4", "5", "6");
+ final List<Integer> output = Functions.stream(input)
+ .map((s) -> Integer.valueOf(s))
+ .filter(asIntPredicate(null))
+ .collect(Collectors.toList());
+ assertEvenNumbers(output);
+
+ output.clear();
+ final IllegalArgumentException iae = new
IllegalArgumentException("Invalid argument: " + 5);
+ try {
+ Functions.stream(input)
+ .map((s) -> Integer.valueOf(s))
+ .filter(asIntPredicate(iae))
+ .collect(Collectors.toList());
+ fail("Expected Exception");
+ } catch (IllegalArgumentException e) {
+ assertSame(iae, e);
+ }
+
+ output.clear();
+ final OutOfMemoryError oome = new OutOfMemoryError();
+ try {
+ Functions.stream(input)
+ .map((s) -> Integer.valueOf(s))
+ .filter(asIntPredicate(oome))
+ .collect(Collectors.toList());
+ fail("Expected Exception");
+ } catch (Throwable t) {
+ assertSame(oome, t);
+ }
+
+ output.clear();
+ final SAXException se = new SAXException();
+ try {
+ Functions.stream(input)
+ .map((s) -> Integer.valueOf(s))
+ .filter(asIntPredicate(se))
+ .collect(Collectors.toList());
+ fail("Expected Exception");
+ } catch (UndeclaredThrowableException t) {
+ assertSame(se, t.getCause());
+ }
+ }
+}
