--- a/src/share/classes/java/util/stream/AbstractPipeline.java	Thu Aug 15 14:35:12 2013 -0700
+++ b/src/share/classes/java/util/stream/AbstractPipeline.java	Fri Aug 16 15:14:39 2013 -0700
@@ -319,6 +319,7 @@
     }
 
     @Override
+    @SuppressWarnings("unchecked")
     public S onClose(Runnable closeHandler) {
         Runnable existingHandler = sourceStage.sourceCloseAction;
         sourceStage.sourceCloseAction =

--- a/src/share/classes/java/util/stream/Collectors.java	Thu Aug 15 14:35:12 2013 -0700
+++ b/src/share/classes/java/util/stream/Collectors.java	Fri Aug 16 15:14:39 2013 -0700
@@ -133,6 +133,11 @@
         return (u,v) -> { throw new IllegalStateException(String.format("Duplicate key %s", u)); };
     }
 
+    @SuppressWarnings("unchecked")
+    private static <I, R> Function<I, R> castingIdentity() {
+        return i -> (R) i;
+    }
+
     /**
      * Simple implementation class for {@code Collector}.
      *
@@ -162,7 +167,7 @@
                       BiConsumer<A, T> accumulator,
                       BinaryOperator<A> combiner,
                       Set<Characteristics> characteristics) {
-            this(supplier, accumulator, combiner, i -> (R) i, characteristics);
+            this(supplier, accumulator, combiner, castingIdentity(), characteristics);
         }
 
         @Override
@@ -205,7 +210,7 @@
      */
     public static <T, C extends Collection<T>>
     Collector<T, ?, C> toCollection(Supplier<C> collectionFactory) {
-        return new CollectorImpl<>(collectionFactory, Collection::add,
+        return new CollectorImpl<>(collectionFactory, Collection<T>::add,
                                    (r1, r2) -> { r1.addAll(r2); return r1; },
                                    CH_ID);
     }
@@ -365,8 +370,8 @@
      * @param <A> intermediate accumulation type of the downstream collector
      * @param <R> result type of the downstream collector
      * @param <RR> result type of the resulting collector
+     * @param downstream a collector
      * @param finisher a function to be applied to the final result of the downstream collector
-     * @param downstream a collector
      * @return a collector which performs the action of the downstream collector,
      * followed by an additional finishing step
      */
@@ -1045,30 +1050,23 @@
     public static <T, D, A>
     Collector<T, ?, Map<Boolean, D>> partitioningBy(Predicate<? super T> predicate,
                                                     Collector<? super T, A, D> downstream) {
-        @SuppressWarnings("unchecked")
-        BiConsumer<D, ? super T> downstreamAccumulator = (BiConsumer<D, ? super T>) downstream.accumulator();
-        BiConsumer<Map<Boolean, A>, T> accumulator = (result, t) -> {
-            Partition<D> asPartition = ((Partition<D>) result);
-            downstreamAccumulator.accept(predicate.test(t) ? asPartition.forTrue : asPartition.forFalse, t);
-        };
+        BiConsumer<A, ? super T> downstreamAccumulator = downstream.accumulator();
+        BiConsumer<Partition<A>, T> accumulator = (result, t) ->
+                downstreamAccumulator.accept(predicate.test(t) ? result.forTrue : result.forFalse, t);
         BinaryOperator<A> op = downstream.combiner();
-        BinaryOperator<Map<Boolean, A>> merger = (m1, m2) -> {
-            Partition<A> left = (Partition<A>) m1;
-            Partition<A> right = (Partition<A>) m2;
-            return new Partition<>(op.apply(left.forTrue, right.forTrue),
-                                   op.apply(left.forFalse, right.forFalse));
-        };
-        Supplier<Map<Boolean, A>> supplier = () -> new Partition<>(downstream.supplier().get(),
-                                                                   downstream.supplier().get());
+        BinaryOperator<Partition<A>> merger = (left, right) ->
+                new Partition<>(op.apply(left.forTrue, right.forTrue),
+                                op.apply(left.forFalse, right.forFalse));
+        Supplier<Partition<A>> supplier = () ->
+                new Partition<>(downstream.supplier().get(),
+                                downstream.supplier().get());
         if (downstream.characteristics().contains(Collector.Characteristics.IDENTITY_FINISH)) {
             return new CollectorImpl<>(supplier, accumulator, merger, CH_ID);
         }
         else {
-            Function<Map<Boolean, A>, Map<Boolean, D>> finisher = (Map<Boolean, A> par) -> {
-                Partition<A> asAPartition = (Partition<A>) par;
-                return new Partition<>(downstream.finisher().apply(asAPartition.forTrue),
-                                       downstream.finisher().apply(asAPartition.forFalse));
-            };
+            Function<Partition<A>, Map<Boolean, D>> finisher = par ->
+                    new Partition<>(downstream.finisher().apply(par.forTrue),
+                                    downstream.finisher().apply(par.forFalse));
             return new CollectorImpl<>(supplier, accumulator, merger, finisher, CH_NOID);
         }
     }

--- a/src/share/classes/java/util/stream/ReferencePipeline.java	Thu Aug 15 14:35:12 2013 -0700
+++ b/src/share/classes/java/util/stream/ReferencePipeline.java	Fri Aug 16 15:14:39 2013 -0700
@@ -499,6 +499,7 @@
     }
 
     @Override
+    @SuppressWarnings("unchecked")
     public final <R, A> R collect(Collector<? super P_OUT, A, R> collector) {
         A container;
         if (isParallel()

--- a/src/share/classes/java/util/stream/SliceOps.java	Thu Aug 15 14:35:12 2013 -0700
+++ b/src/share/classes/java/util/stream/SliceOps.java	Fri Aug 16 15:14:39 2013 -0700
@@ -96,6 +96,11 @@
         }
     }
 
+    @SuppressWarnings("unchecked")
+    private static <T> IntFunction<T[]> castingArray() {
+        return size -> (T[]) new Object[size];
+    }
+
     /**
      * Appends a "slice" operation to the provided stream.  The slice operation
      * may be may be skip-only, limit-only, or skip-and-limit.
@@ -107,12 +112,12 @@
      *        is to be imposed
      */
     public static <T> Stream<T> makeRef(AbstractPipeline<?, T, ?> upstream,
-                                       long skip, long limit) {
+                                        long skip, long limit) {
         if (skip < 0)
             throw new IllegalArgumentException("Skip must be non-negative: " + skip);
 
-        return new ReferencePipeline.StatefulOp<T,T>(upstream, StreamShape.REFERENCE,
-                                                     flags(limit)) {
+        return new ReferencePipeline.StatefulOp<T, T>(upstream, StreamShape.REFERENCE,
+                                                      flags(limit)) {
             Spliterator<T> unorderedSkipLimitSpliterator(Spliterator<T> s,
                                                          long skip, long limit, long sizeIfKnown) {
                 if (skip <= sizeIfKnown) {
@@ -146,7 +151,7 @@
                     //     cancellation will be more aggressive cancelling later tasks
                     //     if the target slice size has been reached from a given task,
                     //     cancellation should also clear local results if any
-                    return new SliceTask<>(this, helper, spliterator, i -> (T[]) new Object[i], skip, limit).
+                    return new SliceTask<>(this, helper, spliterator, castingArray(), skip, limit).
                             invoke().spliterator();
                 }
             }
@@ -560,13 +565,13 @@
 
         private volatile boolean completed;
 
-        SliceTask(AbstractPipeline<?, P_OUT, ?> op,
+        SliceTask(AbstractPipeline<P_OUT, P_OUT, ?> op,
                   PipelineHelper<P_OUT> helper,
                   Spliterator<P_IN> spliterator,
                   IntFunction<P_OUT[]> generator,
                   long offset, long size) {
             super(helper, spliterator);
-            this.op = (AbstractPipeline<P_OUT, P_OUT, ?>) op;
+            this.op = op;
             this.generator = generator;
             this.targetOffset = offset;
             this.targetSize = size;

--- a/src/share/classes/java/util/stream/Stream.java	Thu Aug 15 14:35:12 2013 -0700
+++ b/src/share/classes/java/util/stream/Stream.java	Fri Aug 16 15:14:39 2013 -0700
@@ -873,6 +873,7 @@
      * @return the new stream
      */
     @SafeVarargs
+    @SuppressWarnings("varargs")
     public static<T> Stream<T> of(T... values) {
         return Arrays.stream(values);
     }