Java Stream.iterator方法代碼示例

import java.util.stream.Stream; //導入方法依賴的package包/類
public static Rectangle getBounds(Stream<Node> nodes) {
	final Iterator<Node> i = nodes.iterator();
	if (i.hasNext()) {
		float xMin = Float.MAX_VALUE;
		float xMax = Float.MIN_VALUE;
		float yMin = Float.MAX_VALUE;
		float yMax = Float.MIN_VALUE;
		while (i.hasNext()) {
			final Node n = i.next();
			xMin = Math.min(xMin, n.getX());
			yMin = Math.min(yMin, n.getY());
			xMax = Math.max(xMax, n.getX() + n.getWidth());
			yMax = Math.max(yMax, n.getY() + n.getHeight());
		}
		return new Rectangle(xMin, yMin, xMax - xMin, yMax - yMin);
	} else
		return Rectangle.EMPTY;
}
 

import java.util.stream.Stream; //導入方法依賴的package包/類
public static <T> Stream<T> intersperse(Stream<T> s, T e) {
    final Iterator<T> inner = s.iterator();
    final AtomicBoolean returnE = new AtomicBoolean(false);

    final Iterator<T> it = new Iterator<T>() {
        @Override
        public boolean hasNext() {
            return inner.hasNext();
        }

        @Override
        public T next() {
            final T ret = returnE.get() ? e : inner.next();
            returnE.set(!returnE.get());
            return ret;
        }
    };

    return StreamSupport.stream(
            Spliterators.spliteratorUnknownSize(it, Spliterator.ORDERED),
            false);
}
 

import java.util.stream.Stream; //導入方法依賴的package包/類
/**
 * Method to obtain the paths to all files in a directory specified
 * by a path. This should work in an ordinary file system
 * as well as a (possibly nested) JAR file.
 * 
 * @param path path to a directory (may be contained in a JAR file) 
 * @return a sequence of paths or {@code null} if the specified path 
 * is not a directory
 */
public static Path[] listResources(Path path) {
	// with help from http://stackoverflow.com/questions/1429172/how-do-i-list-the-files-inside-a-jar-file, #10
	if (!Files.isDirectory(path)) {
		throw new IllegalArgumentException("path is not a directory: " + path.toString());
	}
	
	List<Path> pathList = new ArrayList<Path>();
	Stream<Path> walk = null;
	try {
		walk = Files.walk(path, 1);
	} catch (IOException e) {
		e.printStackTrace();
	}

	for (Iterator<Path> it = walk.iterator(); it.hasNext();){
		Path p = it.next();
		if (Files.isRegularFile(p) && Files.isReadable(p)) {
			pathList.add(p);
		}
	}
	walk.close();
	return pathList.toArray(new Path[0]);
}
 

import java.util.stream.Stream; //導入方法依賴的package包/類
/**
 * Variation of {@link Reader#sequence(IList)} for {@link Stream}.
 * @param sfu       the stream of {@code F} values
 * @param <T>       the error type
 * @param <U>       the return type of the {@code F}s in the stream
 * @return          a {@code F} which wraps an {@link Stream} of values
 */
static <T, U> Reader<T, Stream<U>> sequence(Stream<Reader<T, U>> sfu) {
    final Iterator<Reader<T, U>> iter = sfu.iterator();
    Reader<T, IList<U>> flu = pure(IList.nil());
    while (iter.hasNext()) {
        final Reader<T, U> fu = iter.next();
        flu = fu.app(flu.map(lt -> lt::add));
    }
    return flu.map(IList::stream);
}
 

import java.util.stream.Stream; //導入方法依賴的package包/類
/**
 * Lay out given subtrees side by side.
 */
private void doLayoutSubtrees(@SuppressWarnings("hiding") Stream<Node> nodes) {
	float px = 0;
	final Iterator<Node> i = nodes.iterator();
	while (i.hasNext()) {
		final Node n = i.next();
		doLayoutSubtree(n);
		final Rectangle b = GraphUtils.getBounds(getTree(n));
		moveTree(n, px - b.x, 0);
		px += b.width + GAP_X;
	}
}
 

import java.util.stream.Stream; //導入方法依賴的package包/類
public List<String> getMultipleChoiceImageResources(){
		final URI uri;
		final ArrayList<String> resourceList;
		final PathMatcher matcher;
		final Path myPath;
		final Stream<Path> walk;
		resourceList = new ArrayList<String>();
		matcher = FileSystems.getDefault().getPathMatcher(GlobFactoryHelper.getCaseInsensitiveExtensionGlob("PNG","JPG"));
		try {
			uri = ResourceHelper.getResource(isFromGameResourceInput(), gamePath, setPath).toURI();
			myPath= Paths.get(uri);
			walk = Files.walk(myPath, 3, FileVisitOption.FOLLOW_LINKS);
			for (Iterator<Path> it = walk.iterator(); it.hasNext();){
				Path currentPath =it.next();
				if (matcher.matches(currentPath))
				{		resourceList.add(currentPath.toString().substring(currentPath.toString().indexOf("game-resources-input/")));
				}
				}


		} catch (IOException | URISyntaxException e1) {
			log.error("Fail",e1);

		} 
		return resourceList;


		
		
		
		
/*		final String pattern;
		final String resourcePath;
		final List<String> resourceList; 
		pattern=GlobFactoryHelper.getCaseInsensitiveExtensionGlob("PNG","JPG");
		resourcePath= ResourceHelper.getResourceAddress( isFromGameResourceInput(),getGamePath(), getSetPath());
		resourceList= ImageFilesLoaderHelper.getImageResources(pattern, resourcePath, 3, log);
		return resourceList;
	*/
	}
 

import java.util.stream.Stream; //導入方法依賴的package包/類
/**
 * Variation of {@link State#sequence(IList)} for {@link Stream}.
 * @param sst       the stream of {@code State} values
 * @param <S>       the state type
 * @param <T>       the result type of the {@code State}s in the stream
 * @return          a {@code State} which wraps an {@link Stream} of values
 */
static <S, T> State<S, Stream<T>> sequence(Stream<State<S, T>> sst) {
    final Iterator<State<S, T>> iter = sst.iterator();
    State<S, IList<T>> slt = pure(IList.nil());
    while (iter.hasNext()) {
        final State<S, T> st = iter.next();
        slt = st.apply(slt.map(lt -> lt::add));
    }
    return slt.map(IList::stream);
}
 

import java.util.stream.Stream; //導入方法依賴的package包/類
/**
 * Variation of {@link StateR#sequence(IList)} for {@link Stream}.
 * @param sst       the stream of {@code StateR} values
 * @param <S>       the state type
 * @param <T>       the result type of the {@code StateR}s in the stream
 * @return          a {@code StateR} which wraps an {@link Stream} of values
 */
static <S, T> StateR<S, Stream<T>> sequence(Stream<StateR<S, T>> sst) {
    final Iterator<StateR<S, T>> iter = sst.iterator();
    StateR<S, IList<T>> slt = pure(IList.nil());
    while (iter.hasNext()) {
        final StateR<S, T> st = iter.next();
        slt = st.apply(slt.map(lt -> lt::add));
    }
    return slt.map(IList::stream);
}
 

import java.util.stream.Stream; //導入方法依賴的package包/類
public void testInterlacedRead() throws IOException {
    MockLineReader r = new MockLineReader(10);
    BufferedReader br = new BufferedReader(r);
    char[] buf = new char[5];
    Stream<String> s = br.lines();
    Iterator<String> it = s.iterator();

    br.read(buf);
    assertEquals(new String(buf), "Line ");
    assertEquals(it.next(), "1");
    try {
        s.iterator().next();
        fail("Should failed on second attempt to get iterator from s");
    } catch (IllegalStateException ise) {}
    br.read(buf, 0, 2);
    assertEquals(new String(buf, 0, 2), "Li");
    // Get stream again should continue from where left
    // Only read remaining of the line
    br.lines().limit(1L).forEach(line -> assertEquals(line, "ne 2"));
    br.read(buf, 0, 2);
    assertEquals(new String(buf, 0, 2), "Li");
    br.read(buf, 0, 2);
    assertEquals(new String(buf, 0, 2), "ne");
    assertEquals(it.next(), " 3");
    // Line 4
    br.readLine();
    // interator pick
    assertEquals(it.next(), "Line 5");
    // Another stream instantiated by lines()
    AtomicInteger line_no = new AtomicInteger(6);
    br.lines().forEach(l -> assertEquals(l, "Line " + line_no.getAndIncrement()));
    // Read after EOL
    assertFalse(it.hasNext());
}
 

import java.util.stream.Stream; //導入方法依賴的package包/類
/**
 * Returns a new Iterable wrapper of the stream
 * @param stream        the stream to wrap
 * @param <T>           the entity type
 * @return              the newly created iterable
 */
public static <T> Iterable<T> asIterable(Stream<T> stream) {
    return new Iterable<T>() {
        @Override
        public Iterator<T> iterator() {
            return stream.iterator();
        }
    };
}
 

import java.util.stream.Stream; //導入方法依賴的package包/類
public static <T, R> boolean tryScalarXMap(FolyamPublisher<T> source, FolyamSubscriber<? super R> s, CheckedFunction<? super T, ? extends Stream<? extends R>> mapper) {
    if (source instanceof FusedDynamicSource) {
        FusedDynamicSource<T> f = (FusedDynamicSource<T>) source;
        Stream<? extends R> e = null;
        Iterator<? extends R> it = null;
        boolean hasValue = false;

        try {
            T v = f.value();
            if (v != null) {
                e = Objects.requireNonNull(mapper.apply(v), "The mapper returned a null Stream");
                it = e.iterator();
                hasValue = it.hasNext();
            }
        } catch (Throwable ex) {
            FolyamPlugins.handleFatal(ex);
            EmptySubscription.error(s, ex);
            return true;
        }

        if (e == null) {
            EmptySubscription.complete(s);
            return true;
        }

        if (hasValue) {
            if (s instanceof ConditionalSubscriber) {
                s.onSubscribe(new FolyamStream.StreamConditionalSubscription<>((ConditionalSubscriber<? super R>)s, it, e));
            } else {
                s.onSubscribe(new FolyamStream.StreamSubscription<>(s, it, e));
            }
        } else {
            EmptySubscription.complete(s);
        }

        return true;
    }
    return false;
}
 

import java.util.stream.Stream; //導入方法依賴的package包/類
private static <T> Stream<Stream<T>> chunkBy(int chunkSize, Stream<T> stream) {
    Iterator<T> elements = stream.iterator();
    Stream.Builder<Stream<T>> b1 = Stream.builder();
    while (elements.hasNext()) {
        Stream.Builder<T> b2 = Stream.builder();
        for (int i = 0; i < chunkSize && elements.hasNext(); i++) {
            b2.accept(elements.next());
        }
        b1.accept(b2.build());
    }
    return b1.build();
}
 

import java.util.stream.Stream; //導入方法依賴的package包/類
@Override
void assertValue(List<T> value, Supplier<Stream<T>> source, boolean ordered)
        throws ReflectiveOperationException {
    if (!List.class.isAssignableFrom(value.getClass()))
        fail(String.format("Class mismatch in ListAssertion: %s", value.getClass()));
    Stream<T> stream = source.get();
    List<T> result = new ArrayList<>();
    for (Iterator<T> it = stream.iterator(); it.hasNext(); ) // avoid capturing result::add
        result.add(it.next());
    if (StreamOpFlagTestHelper.isStreamOrdered(stream) && ordered)
        assertContents(value, result);
    else
        assertContentsUnordered(value, result);
}
 

import java.util.stream.Stream; //導入方法依賴的package包/類
private <T extends Snippet> void identityMatch(Stream<T> got, T expected) {
    Iterator<T> it = got.iterator();
    assertTrue(it.hasNext(), "expected exactly one");
    assertTrue(expected == it.next(), "Identity must not change");
    assertFalse(it.hasNext(), "expected exactly one");
}
 

import java.util.stream.Stream; //導入方法依賴的package包/類
public static <T, E extends Throwable> void forEachThrows(Stream<T> stream, ThrowingConsumer<? super T, E> consumer) throws E {
    for(final Iterator<T> it = stream.iterator(); it.hasNext();) {
        consumer.acceptThrows(it.next());
    }
}