8025910: rename substream(long) -> skip and remove substream(long,long)

Reviewed-by: psandoz, henryjen

src/share/classes/java/util/stream/DoublePipeline.java

@@ -340,24 +340,17 @@ abstract class DoublePipeline<E_IN>
     }
 
     @Override
-    public final DoubleStream substream(long startingOffset) {
-        if (startingOffset < 0)
-            throw new IllegalArgumentException(Long.toString(startingOffset));
-        if (startingOffset == 0)
+    public final DoubleStream skip(long n) {
+        if (n < 0)
+            throw new IllegalArgumentException(Long.toString(n));
+        if (n == 0)
             return this;
         else {
             long limit = -1;
-            return SliceOps.makeDouble(this, startingOffset, limit);
+            return SliceOps.makeDouble(this, n, limit);
         }
     }
 
-    @Override
-    public final DoubleStream substream(long startingOffset, long endingOffset) {
-        if (startingOffset < 0 || endingOffset < startingOffset)
-            throw new IllegalArgumentException(String.format("substream(%d, %d)", startingOffset, endingOffset));
-        return SliceOps.makeDouble(this, startingOffset, endingOffset - startingOffset);
-    }
-
     @Override
     public final DoubleStream sorted() {
         return SortedOps.makeDouble(this);

src/share/classes/java/util/stream/DoubleStream.java

@@ -289,6 +289,20 @@ public interface DoubleStream extends BaseStream<Double, DoubleStream> {
      * <p>This is a <a href="package-summary.html#StreamOps">short-circuiting
      * stateful intermediate operation</a>.
      *
+     * @apiNote
+     * While {@code limit()} is generally a cheap operation on sequential
+     * stream pipelines, it can be quite expensive on ordered parallel pipelines,
+     * especially for large values of {@code maxSize}, since {@code limit(n)}
+     * is constrained to return not just any <em>n</em> elements, but the
+     * <em>first n</em> elements in the encounter order.  Using an unordered
+     * stream source (such as {@link #generate(DoubleSupplier)}) or removing the
+     * ordering constraint with {@link #unordered()} may result in significant
+     * speedups of {@code limit()} in parallel pipelines, if the semantics of
+     * your situation permit.  If consistency with encounter order is required,
+     * and you are experiencing poor performance or memory utilization with
+     * {@code limit()} in parallel pipelines, switching to sequential execution
+     * with {@link #sequential()} may improve performance.
+     *
      * @param maxSize the number of elements the stream should be limited to
      * @return the new stream
      * @throws IllegalArgumentException if {@code maxSize} is negative
@@ -297,37 +311,32 @@ public interface DoubleStream extends BaseStream<Double, DoubleStream> {
 
     /**
      * Returns a stream consisting of the remaining elements of this stream
-     * after discarding the first {@code startInclusive} elements of the stream.
-     * If this stream contains fewer than {@code startInclusive} elements then an
+     * after discarding the first {@code n} elements of the stream.
+     * If this stream contains fewer than {@code n} elements then an
      * empty stream will be returned.
      *
      * <p>This is a <a href="package-summary.html#StreamOps">stateful
      * intermediate operation</a>.
      *
-     * @param startInclusive the number of leading elements to skip
-     * @return the new stream
-     * @throws IllegalArgumentException if {@code startInclusive} is negative
-     */
-    DoubleStream substream(long startInclusive);
-
-    /**
-     * Returns a stream consisting of the remaining elements of this stream
-     * after discarding the first {@code startInclusive} elements and truncating
-     * the result to be no longer than {@code endExclusive - startInclusive}
-     * elements in length. If this stream contains fewer than
-     * {@code startInclusive} elements then an empty stream will be returned.
-     *
-     * <p>This is a <a href="package-summary.html#StreamOps">short-circuiting
-     * stateful intermediate operation</a>.
-     *
-     * @param startInclusive the starting position of the substream, inclusive
-     * @param endExclusive the ending position of the substream, exclusive
+     * @apiNote
+     * While {@code skip()} is generally a cheap operation on sequential
+     * stream pipelines, it can be quite expensive on ordered parallel pipelines,
+     * especially for large values of {@code n}, since {@code skip(n)}
+     * is constrained to skip not just any <em>n</em> elements, but the
+     * <em>first n</em> elements in the encounter order.  Using an unordered
+     * stream source (such as {@link #generate(DoubleSupplier)}) or removing the
+     * ordering constraint with {@link #unordered()} may result in significant
+     * speedups of {@code skip()} in parallel pipelines, if the semantics of
+     * your situation permit.  If consistency with encounter order is required,
+     * and you are experiencing poor performance or memory utilization with
+     * {@code skip()} in parallel pipelines, switching to sequential execution
+     * with {@link #sequential()} may improve performance.
+     *
+     * @param n the number of leading elements to skip
      * @return the new stream
-     * @throws IllegalArgumentException if {@code startInclusive} or
-     * {@code endExclusive} is negative or {@code startInclusive} is greater
-     * than {@code endExclusive}
+     * @throws IllegalArgumentException if {@code n} is negative
      */
-    DoubleStream substream(long startInclusive, long endExclusive);
+    DoubleStream skip(long n);
 
     /**
      * Performs an action for each element of this stream.

src/share/classes/java/util/stream/IntPipeline.java

@@ -368,32 +368,21 @@ abstract class IntPipeline<E_IN>
 
     // Stateful intermediate ops from IntStream
 
-    private IntStream slice(long skip, long limit) {
-        return SliceOps.makeInt(this, skip, limit);
-    }
-
     @Override
     public final IntStream limit(long maxSize) {
         if (maxSize < 0)
             throw new IllegalArgumentException(Long.toString(maxSize));
-        return slice(0, maxSize);
+        return SliceOps.makeInt(this, 0, maxSize);
     }
 
     @Override
-    public final IntStream substream(long startingOffset) {
-        if (startingOffset < 0)
-            throw new IllegalArgumentException(Long.toString(startingOffset));
-        if (startingOffset == 0)
+    public final IntStream skip(long n) {
+        if (n < 0)
+            throw new IllegalArgumentException(Long.toString(n));
+        if (n == 0)
             return this;
         else
-            return slice(startingOffset, -1);
-    }
-
-    @Override
-    public final IntStream substream(long startingOffset, long endingOffset) {
-        if (startingOffset < 0 || endingOffset < startingOffset)
-            throw new IllegalArgumentException(String.format("substream(%d, %d)", startingOffset, endingOffset));
-        return slice(startingOffset, endingOffset - startingOffset);
+            return SliceOps.makeInt(this, n, -1);
     }
 
     @Override

src/share/classes/java/util/stream/IntStream.java

@@ -287,6 +287,20 @@ public interface IntStream extends BaseStream<Integer, IntStream> {
      * <p>This is a <a href="package-summary.html#StreamOps">short-circuiting
      * stateful intermediate operation</a>.
      *
+     * @apiNote
+     * While {@code limit()} is generally a cheap operation on sequential
+     * stream pipelines, it can be quite expensive on ordered parallel pipelines,
+     * especially for large values of {@code maxSize}, since {@code limit(n)}
+     * is constrained to return not just any <em>n</em> elements, but the
+     * <em>first n</em> elements in the encounter order.  Using an unordered
+     * stream source (such as {@link #generate(IntSupplier)}) or removing the
+     * ordering constraint with {@link #unordered()} may result in significant
+     * speedups of {@code limit()} in parallel pipelines, if the semantics of
+     * your situation permit.  If consistency with encounter order is required,
+     * and you are experiencing poor performance or memory utilization with
+     * {@code limit()} in parallel pipelines, switching to sequential execution
+     * with {@link #sequential()} may improve performance.
+     *
      * @param maxSize the number of elements the stream should be limited to
      * @return the new stream
      * @throws IllegalArgumentException if {@code maxSize} is negative
@@ -295,37 +309,32 @@ public interface IntStream extends BaseStream<Integer, IntStream> {
 
     /**
      * Returns a stream consisting of the remaining elements of this stream
-     * after discarding the first {@code startInclusive} elements of the stream.
-     * If this stream contains fewer than {@code startInclusive} elements then an
+     * after discarding the first {@code n} elements of the stream.
+     * If this stream contains fewer than {@code n} elements then an
      * empty stream will be returned.
      *
      * <p>This is a <a href="package-summary.html#StreamOps">stateful
      * intermediate operation</a>.
      *
-     * @param startInclusive the number of leading elements to skip
-     * @return the new stream
-     * @throws IllegalArgumentException if {@code startInclusive} is negative
-     */
-    IntStream substream(long startInclusive);
-
-    /**
-     * Returns a stream consisting of the remaining elements of this stream
-     * after discarding the first {@code startInclusive} elements and truncating
-     * the result to be no longer than {@code endExclusive - startInclusive}
-     * elements in length. If this stream contains fewer than
-     * {@code startInclusive} elements then an empty stream will be returned.
-     *
-     * <p>This is a <a href="package-summary.html#StreamOps">short-circuiting
-     * stateful intermediate operation</a>.
-     *
-     * @param startInclusive the starting position of the substream, inclusive
-     * @param endExclusive the ending position of the substream, exclusive
+     * @apiNote
+     * While {@code skip()} is generally a cheap operation on sequential
+     * stream pipelines, it can be quite expensive on ordered parallel pipelines,
+     * especially for large values of {@code n}, since {@code skip(n)}
+     * is constrained to skip not just any <em>n</em> elements, but the
+     * <em>first n</em> elements in the encounter order.  Using an unordered
+     * stream source (such as {@link #generate(IntSupplier)}) or removing the
+     * ordering constraint with {@link #unordered()} may result in significant
+     * speedups of {@code skip()} in parallel pipelines, if the semantics of
+     * your situation permit.  If consistency with encounter order is required,
+     * and you are experiencing poor performance or memory utilization with
+     * {@code skip()} in parallel pipelines, switching to sequential execution
+     * with {@link #sequential()} may improve performance.
+     *
+     * @param n the number of leading elements to skip
      * @return the new stream
-     * @throws IllegalArgumentException if {@code startInclusive} or
-     * {@code endExclusive} is negative or {@code startInclusive} is greater
-     * than {@code endExclusive}
+     * @throws IllegalArgumentException if {@code n} is negative
      */
-    IntStream substream(long startInclusive, long endExclusive);
+    IntStream skip(long n);
 
     /**
      * Performs an action for each element of this stream.

src/share/classes/java/util/stream/LongPipeline.java

@@ -349,32 +349,21 @@ abstract class LongPipeline<E_IN>
 
     // Stateful intermediate ops from LongStream
 
-    private LongStream slice(long skip, long limit) {
-        return SliceOps.makeLong(this, skip, limit);
-    }
-
     @Override
     public final LongStream limit(long maxSize) {
         if (maxSize < 0)
             throw new IllegalArgumentException(Long.toString(maxSize));
-        return slice(0, maxSize);
+        return SliceOps.makeLong(this, 0, maxSize);
     }
 
     @Override
-    public final LongStream substream(long startingOffset) {
-        if (startingOffset < 0)
-            throw new IllegalArgumentException(Long.toString(startingOffset));
-        if (startingOffset == 0)
+    public final LongStream skip(long n) {
+        if (n < 0)
+            throw new IllegalArgumentException(Long.toString(n));
+        if (n == 0)
             return this;
         else
-            return slice(startingOffset, -1);
-    }
-
-    @Override
-    public final LongStream substream(long startingOffset, long endingOffset) {
-        if (startingOffset < 0 || endingOffset < startingOffset)
-            throw new IllegalArgumentException(String.format("substream(%d, %d)", startingOffset, endingOffset));
-        return slice(startingOffset, endingOffset - startingOffset);
+            return SliceOps.makeLong(this, n, -1);
     }
 
     @Override

src/share/classes/java/util/stream/LongStream.java

@@ -287,6 +287,20 @@ public interface LongStream extends BaseStream<Long, LongStream> {
      * <p>This is a <a href="package-summary.html#StreamOps">short-circuiting
      * stateful intermediate operation</a>.
      *
+     * @apiNote
+     * While {@code limit()} is generally a cheap operation on sequential
+     * stream pipelines, it can be quite expensive on ordered parallel pipelines,
+     * especially for large values of {@code maxSize}, since {@code limit(n)}
+     * is constrained to return not just any <em>n</em> elements, but the
+     * <em>first n</em> elements in the encounter order.  Using an unordered
+     * stream source (such as {@link #generate(LongSupplier)}) or removing the
+     * ordering constraint with {@link #unordered()} may result in significant
+     * speedups of {@code limit()} in parallel pipelines, if the semantics of
+     * your situation permit.  If consistency with encounter order is required,
+     * and you are experiencing poor performance or memory utilization with
+     * {@code limit()} in parallel pipelines, switching to sequential execution
+     * with {@link #sequential()} may improve performance.
+     *
      * @param maxSize the number of elements the stream should be limited to
      * @return the new stream
      * @throws IllegalArgumentException if {@code maxSize} is negative
@@ -295,37 +309,32 @@ public interface LongStream extends BaseStream<Long, LongStream> {
 
     /**
      * Returns a stream consisting of the remaining elements of this stream
-     * after discarding the first {@code startInclusive} elements of the stream.
-     * If this stream contains fewer than {@code startInclusive} elements then an
+     * after discarding the first {@code n} elements of the stream.
+     * If this stream contains fewer than {@code n} elements then an
      * empty stream will be returned.
      *
      * <p>This is a <a href="package-summary.html#StreamOps">stateful
      * intermediate operation</a>.
      *
-     * @param startInclusive the number of leading elements to skip
-     * @return the new stream
-     * @throws IllegalArgumentException if {@code startInclusive} is negative
-     */
-    LongStream substream(long startInclusive);
-
-    /**
-     * Returns a stream consisting of the remaining elements of this stream
-     * after discarding the first {@code startInclusive} elements and truncating
-     * the result to be no longer than {@code endExclusive - startInclusive}
-     * elements in length. If this stream contains fewer than
-     * {@code startInclusive} elements then an empty stream will be returned.
-     *
-     * <p>This is a <a href="package-summary.html#StreamOps">short-circuiting
-     * stateful intermediate operation</a>.
-     *
-     * @param startInclusive the starting position of the substream, inclusive
-     * @param endExclusive the ending position of the substream, exclusive
+     * @apiNote
+     * While {@code skip()} is generally a cheap operation on sequential
+     * stream pipelines, it can be quite expensive on ordered parallel pipelines,
+     * especially for large values of {@code n}, since {@code skip(n)}
+     * is constrained to skip not just any <em>n</em> elements, but the
+     * <em>first n</em> elements in the encounter order.  Using an unordered
+     * stream source (such as {@link #generate(LongSupplier)}) or removing the
+     * ordering constraint with {@link #unordered()} may result in significant
+     * speedups of {@code skip()} in parallel pipelines, if the semantics of
+     * your situation permit.  If consistency with encounter order is required,
+     * and you are experiencing poor performance or memory utilization with
+     * {@code skip()} in parallel pipelines, switching to sequential execution
+     * with {@link #sequential()} may improve performance.
+     *
+     * @param n the number of leading elements to skip
      * @return the new stream
-     * @throws IllegalArgumentException if {@code startInclusive} or
-     * {@code endExclusive} is negative or {@code startInclusive} is greater
-     * than {@code endExclusive}
+     * @throws IllegalArgumentException if {@code n} is negative
      */
-    LongStream substream(long startInclusive, long endExclusive);
+    LongStream skip(long n);
 
     /**
      * Performs an action for each element of this stream.

src/share/classes/java/util/stream/ReferencePipeline.java

@@ -394,32 +394,21 @@ abstract class ReferencePipeline<P_IN, P_OUT>
         return SortedOps.makeRef(this, comparator);
     }
 
-    private Stream<P_OUT> slice(long skip, long limit) {
-        return SliceOps.makeRef(this, skip, limit);
-    }
-
     @Override
     public final Stream<P_OUT> limit(long maxSize) {
         if (maxSize < 0)
             throw new IllegalArgumentException(Long.toString(maxSize));
-        return slice(0, maxSize);
+        return SliceOps.makeRef(this, 0, maxSize);
     }
 
     @Override
-    public final Stream<P_OUT> substream(long startingOffset) {
-        if (startingOffset < 0)
-            throw new IllegalArgumentException(Long.toString(startingOffset));
-        if (startingOffset == 0)
+    public final Stream<P_OUT> skip(long n) {
+        if (n < 0)
+            throw new IllegalArgumentException(Long.toString(n));
+        if (n == 0)
             return this;
         else
-            return slice(startingOffset, -1);
-    }
-
-    @Override
-    public final Stream<P_OUT> substream(long startingOffset, long endingOffset) {
-        if (startingOffset < 0 || endingOffset < startingOffset)
-            throw new IllegalArgumentException(String.format("substream(%d, %d)", startingOffset, endingOffset));
-        return slice(startingOffset, endingOffset - startingOffset);
+            return SliceOps.makeRef(this, n, -1);
     }
 
     // Terminal operations from Stream

src/share/classes/java/util/stream/Stream.java

@@ -365,6 +365,20 @@ public interface Stream<T> extends BaseStream<T, Stream<T>> {
      * <p>This is a <a href="package-summary.html#StreamOps">short-circuiting
      * stateful intermediate operation</a>.
      *
+     * @apiNote
+     * While {@code limit()} is generally a cheap operation on sequential
+     * stream pipelines, it can be quite expensive on ordered parallel pipelines,
+     * especially for large values of {@code maxSize}, since {@code limit(n)}
+     * is constrained to return not just any <em>n</em> elements, but the
+     * <em>first n</em> elements in the encounter order.  Using an unordered
+     * stream source (such as {@link #generate(Supplier)}) or removing the
+     * ordering constraint with {@link #unordered()} may result in significant
+     * speedups of {@code limit()} in parallel pipelines, if the semantics of
+     * your situation permit.  If consistency with encounter order is required,
+     * and you are experiencing poor performance or memory utilization with
+     * {@code limit()} in parallel pipelines, switching to sequential execution
+     * with {@link #sequential()} may improve performance.
+     *
      * @param maxSize the number of elements the stream should be limited to
      * @return the new stream
      * @throws IllegalArgumentException if {@code maxSize} is negative
@@ -373,37 +387,32 @@ public interface Stream<T> extends BaseStream<T, Stream<T>> {
 
     /**
      * Returns a stream consisting of the remaining elements of this stream
-     * after discarding the first {@code startInclusive} elements of the stream.
-     * If this stream contains fewer than {@code startInclusive} elements then an
+     * after discarding the first {@code n} elements of the stream.
+     * If this stream contains fewer than {@code n} elements then an
      * empty stream will be returned.
      *
      * <p>This is a <a href="package-summary.html#StreamOps">stateful
      * intermediate operation</a>.
      *
-     * @param startInclusive the number of leading elements to skip
-     * @return the new stream
-     * @throws IllegalArgumentException if {@code startInclusive} is negative
-     */
-    Stream<T> substream(long startInclusive);
-
-    /**
-     * Returns a stream consisting of the remaining elements of this stream
-     * after discarding the first {@code startInclusive} elements and truncating
-     * the result to be no longer than {@code endExclusive - startInclusive}
-     * elements in length. If this stream contains fewer than
-     * {@code startInclusive} elements then an empty stream will be returned.
-     *
-     * <p>This is a <a href="package-summary.html#StreamOps">short-circuiting
-     * stateful intermediate operation</a>.
-     *
-     * @param startInclusive the starting position of the substream, inclusive
-     * @param endExclusive the ending position of the substream, exclusive
+     * @apiNote
+     * While {@code skip()} is generally a cheap operation on sequential
+     * stream pipelines, it can be quite expensive on ordered parallel pipelines,
+     * especially for large values of {@code n}, since {@code skip(n)}
+     * is constrained to skip not just any <em>n</em> elements, but the
+     * <em>first n</em> elements in the encounter order.  Using an unordered
+     * stream source (such as {@link #generate(Supplier)}) or removing the
+     * ordering constraint with {@link #unordered()} may result in significant
+     * speedups of {@code skip()} in parallel pipelines, if the semantics of
+     * your situation permit.  If consistency with encounter order is required,
+     * and you are experiencing poor performance or memory utilization with
+     * {@code skip()} in parallel pipelines, switching to sequential execution
+     * with {@link #sequential()} may improve performance.
+     *
+     * @param n the number of leading elements to skip
      * @return the new stream
-     * @throws IllegalArgumentException if {@code startInclusive} or
-     * {@code endExclusive} is negative or {@code startInclusive} is greater
-     * than {@code endExclusive}
+     * @throws IllegalArgumentException if {@code n} is negative
      */
-    Stream<T> substream(long startInclusive, long endExclusive);
+    Stream<T> skip(long n);
 
     /**
      * Performs an action for each element of this stream.

test/java/util/stream/boottest/java/util/stream/SpinedBufferTest.java

@@ -109,7 +109,7 @@ public class SpinedBufferTest {
 
         List<Integer> end = Arrays.stream(array)
                 .boxed()
-                .substream(array.length - lastSplitSize)
+                .skip(array.length - lastSplitSize)
                 .collect(Collectors.toList());
         assertEquals(contentOfLastSplit, end);
     }
@@ -184,7 +184,7 @@ public class SpinedBufferTest {
 
         List<Integer> end = Arrays.stream(array)
                 .boxed()
-                .substream(array.length - lastSplitSize)
+                .skip(array.length - lastSplitSize)
                 .collect(Collectors.toList());
         assertEquals(contentOfLastSplit, end);
     }
@@ -259,7 +259,7 @@ public class SpinedBufferTest {
 
         List<Long> end = Arrays.stream(array)
                 .boxed()
-                .substream(array.length - lastSplitSize)
+                .skip(array.length - lastSplitSize)
                 .collect(Collectors.toList());
         assertEquals(contentOfLastSplit, end);
     }
@@ -335,7 +335,7 @@ public class SpinedBufferTest {
 
         List<Double> end = Arrays.stream(array)
                 .boxed()
-                .substream(array.length - lastSplitSize)
+                .skip(array.length - lastSplitSize)
                 .collect(Collectors.toList());
         assertEquals(contentOfLastSplit, end);
     }

test/java/util/stream/test/org/openjdk/tests/java/util/stream/InfiniteStreamWithLimitOpTest.java

@@ -63,10 +63,8 @@ public class InfiniteStreamWithLimitOpTest extends OpTestCase {
 
         data.add(new Object[]{f.apply("Stream.limit(%d)"),
                 (UnaryOperator<Stream>) s -> s.limit(SKIP_LIMIT_SIZE)});
-        data.add(new Object[]{f.apply("Stream.substream(%d)"),
-                (UnaryOperator<Stream>) s -> s.substream(SKIP_LIMIT_SIZE, SKIP_LIMIT_SIZE * 2)});
-        data.add(new Object[]{f.apply("Stream.substream(%1$d).limit(%1$d)"),
-                (UnaryOperator<Stream>) s -> s.substream(SKIP_LIMIT_SIZE).limit(SKIP_LIMIT_SIZE)});
+        data.add(new Object[]{f.apply("Stream.skip(%1$d).limit(%1$d)"),
+                (UnaryOperator<Stream>) s -> s.skip(SKIP_LIMIT_SIZE).limit(SKIP_LIMIT_SIZE)});
 
         return data.toArray(new Object[0][]);
     }
@@ -79,10 +77,8 @@ public class InfiniteStreamWithLimitOpTest extends OpTestCase {
 
         data.add(new Object[]{f.apply("IntStream.limit(%d)"),
                 (UnaryOperator<IntStream>) s -> s.limit(SKIP_LIMIT_SIZE)});
-        data.add(new Object[]{f.apply("IntStream.substream(%d)"),
-                (UnaryOperator<IntStream>) s -> s.substream(SKIP_LIMIT_SIZE, SKIP_LIMIT_SIZE * 2)});
-        data.add(new Object[]{f.apply("IntStream.substream(%1$d).limit(%1$d)"),
-                (UnaryOperator<IntStream>) s -> s.substream(SKIP_LIMIT_SIZE).limit(SKIP_LIMIT_SIZE)});
+        data.add(new Object[]{f.apply("IntStream.skip(%1$d).limit(%1$d)"),
+                (UnaryOperator<IntStream>) s -> s.skip(SKIP_LIMIT_SIZE).limit(SKIP_LIMIT_SIZE)});
 
         return data.toArray(new Object[0][]);
     }
@@ -95,10 +91,8 @@ public class InfiniteStreamWithLimitOpTest extends OpTestCase {
 
         data.add(new Object[]{f.apply("LongStream.limit(%d)"),
                 (UnaryOperator<LongStream>) s -> s.limit(SKIP_LIMIT_SIZE)});
-        data.add(new Object[]{f.apply("LongStream.substream(%d)"),
-                (UnaryOperator<LongStream>) s -> s.substream(SKIP_LIMIT_SIZE, SKIP_LIMIT_SIZE * 2)});
-        data.add(new Object[]{f.apply("LongStream.substream(%1$d).limit(%1$d)"),
-                (UnaryOperator<LongStream>) s -> s.substream(SKIP_LIMIT_SIZE).limit(SKIP_LIMIT_SIZE)});
+        data.add(new Object[]{f.apply("LongStream.skip(%1$d).limit(%1$d)"),
+                (UnaryOperator<LongStream>) s -> s.skip(SKIP_LIMIT_SIZE).limit(SKIP_LIMIT_SIZE)});
 
         return data.toArray(new Object[0][]);
     }
@@ -111,10 +105,8 @@ public class InfiniteStreamWithLimitOpTest extends OpTestCase {
 
         data.add(new Object[]{f.apply("DoubleStream.limit(%d)"),
                 (UnaryOperator<DoubleStream>) s -> s.limit(SKIP_LIMIT_SIZE)});
-        data.add(new Object[]{f.apply("DoubleStream.substream(%d)"),
-                (UnaryOperator<DoubleStream>) s -> s.substream(SKIP_LIMIT_SIZE, SKIP_LIMIT_SIZE * 2)});
-        data.add(new Object[]{f.apply("DoubleStream.substream(%1$d).limit(%1$d)"),
-                (UnaryOperator<DoubleStream>) s -> s.substream(SKIP_LIMIT_SIZE).limit(SKIP_LIMIT_SIZE)});
+        data.add(new Object[]{f.apply("DoubleStream.skip(%1$d).limit(%1$d)"),
+                (UnaryOperator<DoubleStream>) s -> s.skip(SKIP_LIMIT_SIZE).limit(SKIP_LIMIT_SIZE)});
 
         return data.toArray(new Object[0][]);
     }

test/java/util/stream/test/org/openjdk/tests/java/util/stream/IntSliceOpTest.java

@@ -44,27 +44,27 @@ public class IntSliceOpTest extends OpTestCase {
     private static final int[] EMPTY_INT_ARRAY = new int[0];
 
     public void testSkip() {
-        assertCountSum(IntStream.range(0, 0).substream(0).boxed(), 0, 0);
-        assertCountSum(IntStream.range(0, 0).substream(4).boxed(), 0, 0);
-        assertCountSum(IntStream.range(1, 5).substream(4).boxed(), 0, 0);
-        assertCountSum(IntStream.range(1, 5).substream(2).boxed(), 2, 7);
-        assertCountSum(IntStream.range(1, 5).substream(0).boxed(), 4, 10);
+        assertCountSum(IntStream.range(0, 0).skip(0).boxed(), 0, 0);
+        assertCountSum(IntStream.range(0, 0).skip(4).boxed(), 0, 0);
+        assertCountSum(IntStream.range(1, 5).skip(4).boxed(), 0, 0);
+        assertCountSum(IntStream.range(1, 5).skip(2).boxed(), 2, 7);
+        assertCountSum(IntStream.range(1, 5).skip(0).boxed(), 4, 10);
 
-        assertCountSum(IntStream.range(0, 0).parallel().substream(0).boxed(), 0, 0);
-        assertCountSum(IntStream.range(0, 0).parallel().substream(4).boxed(), 0, 0);
-        assertCountSum(IntStream.range(1, 5).parallel().substream(4).boxed(), 0, 0);
-        assertCountSum(IntStream.range(1, 5).parallel().substream(2).boxed(), 2, 7);
-        assertCountSum(IntStream.range(1, 5).parallel().substream(0).boxed(), 4, 10);
+        assertCountSum(IntStream.range(0, 0).parallel().skip(0).boxed(), 0, 0);
+        assertCountSum(IntStream.range(0, 0).parallel().skip(4).boxed(), 0, 0);
+        assertCountSum(IntStream.range(1, 5).parallel().skip(4).boxed(), 0, 0);
+        assertCountSum(IntStream.range(1, 5).parallel().skip(2).boxed(), 2, 7);
+        assertCountSum(IntStream.range(1, 5).parallel().skip(0).boxed(), 4, 10);
 
-        exerciseOps(EMPTY_INT_ARRAY, s -> s.substream(0), EMPTY_INT_ARRAY);
-        exerciseOps(EMPTY_INT_ARRAY, s -> s.substream(10), EMPTY_INT_ARRAY);
+        exerciseOps(EMPTY_INT_ARRAY, s -> s.skip(0), EMPTY_INT_ARRAY);
+        exerciseOps(EMPTY_INT_ARRAY, s -> s.skip(10), EMPTY_INT_ARRAY);
 
-        exerciseOps(IntStream.range(1, 2).toArray(), s -> s.substream(0), IntStream.range(1, 2).toArray());
-        exerciseOps(IntStream.range(1, 2).toArray(), s -> s.substream(1), EMPTY_INT_ARRAY);
-        exerciseOps(IntStream.range(1, 101).toArray(), s -> s.substream(0), IntStream.range(1, 101).toArray());
-        exerciseOps(IntStream.range(1, 101).toArray(), s -> s.substream(10), IntStream.range(11, 101).toArray());
-        exerciseOps(IntStream.range(1, 101).toArray(), s -> s.substream(100), EMPTY_INT_ARRAY);
-        exerciseOps(IntStream.range(1, 101).toArray(), s -> s.substream(200), EMPTY_INT_ARRAY);
+        exerciseOps(IntStream.range(1, 2).toArray(), s -> s.skip(0), IntStream.range(1, 2).toArray());
+        exerciseOps(IntStream.range(1, 2).toArray(), s -> s.skip(1), EMPTY_INT_ARRAY);
+        exerciseOps(IntStream.range(1, 101).toArray(), s -> s.skip(0), IntStream.range(1, 101).toArray());
+        exerciseOps(IntStream.range(1, 101).toArray(), s -> s.skip(10), IntStream.range(11, 101).toArray());
+        exerciseOps(IntStream.range(1, 101).toArray(), s -> s.skip(100), EMPTY_INT_ARRAY);
+        exerciseOps(IntStream.range(1, 101).toArray(), s -> s.skip(200), EMPTY_INT_ARRAY);
     }
 
     public void testLimit() {
@@ -92,41 +92,23 @@ public class IntSliceOpTest extends OpTestCase {
     }
 
     public void testSkipLimit() {
-        exerciseOps(EMPTY_INT_ARRAY, s -> s.substream(0).limit(0), EMPTY_INT_ARRAY);
-        exerciseOps(EMPTY_INT_ARRAY, s -> s.substream(0).limit(10), EMPTY_INT_ARRAY);
-        exerciseOps(EMPTY_INT_ARRAY, s -> s.substream(10).limit(0), EMPTY_INT_ARRAY);
-        exerciseOps(EMPTY_INT_ARRAY, s -> s.substream(10).limit(10), EMPTY_INT_ARRAY);
-
-        exerciseOps(IntStream.range(1, 101).toArray(), s -> s.substream(0).limit(100), IntStream.range(1, 101).toArray());
-        exerciseOps(IntStream.range(1, 101).toArray(), s -> s.substream(0).limit(10), IntStream.range(1, 11).toArray());
-        exerciseOps(IntStream.range(1, 101).toArray(), s -> s.substream(0).limit(0), EMPTY_INT_ARRAY);
-        exerciseOps(IntStream.range(1, 101).toArray(), s -> s.substream(10).limit(100), IntStream.range(11, 101).toArray());
-        exerciseOps(IntStream.range(1, 101).toArray(), s -> s.substream(10).limit(10), IntStream.range(11, 21).toArray());
-        exerciseOps(IntStream.range(1, 101).toArray(), s -> s.substream(10).limit(0), EMPTY_INT_ARRAY);
-        exerciseOps(IntStream.range(1, 101).toArray(), s -> s.substream(100).limit(100), EMPTY_INT_ARRAY);
-        exerciseOps(IntStream.range(1, 101).toArray(), s -> s.substream(100).limit(10), EMPTY_INT_ARRAY);
-        exerciseOps(IntStream.range(1, 101).toArray(), s -> s.substream(100).limit(0), EMPTY_INT_ARRAY);
-        exerciseOps(IntStream.range(1, 101).toArray(), s -> s.substream(200).limit(100), EMPTY_INT_ARRAY);
-        exerciseOps(IntStream.range(1, 101).toArray(), s -> s.substream(200).limit(10), EMPTY_INT_ARRAY);
-        exerciseOps(IntStream.range(1, 101).toArray(), s -> s.substream(200).limit(0), EMPTY_INT_ARRAY);
-    }
-
-    public void testSlice() {
-        exerciseOps(EMPTY_INT_ARRAY, s -> s.substream(0, 0), EMPTY_INT_ARRAY);
-        exerciseOps(EMPTY_INT_ARRAY, s -> s.substream(10, 10), EMPTY_INT_ARRAY);
-
-        exerciseOps(IntStream.range(1, 101).toArray(), s -> s.substream(0, 100), IntStream.range(1, 101).toArray());
-        exerciseOps(IntStream.range(1, 101).toArray(), s -> s.substream(0, 10), IntStream.range(1, 11).toArray());
-        exerciseOps(IntStream.range(1, 101).toArray(), s -> s.substream(0, 0), EMPTY_INT_ARRAY);
-        exerciseOps(IntStream.range(1, 101).toArray(), s -> s.substream(10, 110), IntStream.range(11, 101).toArray());
-        exerciseOps(IntStream.range(1, 101).toArray(), s -> s.substream(10, 20), IntStream.range(11, 21).toArray());
-        exerciseOps(IntStream.range(1, 101).toArray(), s -> s.substream(10, 10), EMPTY_INT_ARRAY);
-        exerciseOps(IntStream.range(1, 101).toArray(), s -> s.substream(100, 200), EMPTY_INT_ARRAY);
-        exerciseOps(IntStream.range(1, 101).toArray(), s -> s.substream(100, 110), EMPTY_INT_ARRAY);
-        exerciseOps(IntStream.range(1, 101).toArray(), s -> s.substream(100, 100), EMPTY_INT_ARRAY);
-        exerciseOps(IntStream.range(1, 101).toArray(), s -> s.substream(200, 300), EMPTY_INT_ARRAY);
-        exerciseOps(IntStream.range(1, 101).toArray(), s -> s.substream(200, 210), EMPTY_INT_ARRAY);
-        exerciseOps(IntStream.range(1, 101).toArray(), s -> s.substream(200, 200), EMPTY_INT_ARRAY);
+        exerciseOps(EMPTY_INT_ARRAY, s -> s.skip(0).limit(0), EMPTY_INT_ARRAY);
+        exerciseOps(EMPTY_INT_ARRAY, s -> s.skip(0).limit(10), EMPTY_INT_ARRAY);
+        exerciseOps(EMPTY_INT_ARRAY, s -> s.skip(10).limit(0), EMPTY_INT_ARRAY);
+        exerciseOps(EMPTY_INT_ARRAY, s -> s.skip(10).limit(10), EMPTY_INT_ARRAY);
+
+        exerciseOps(IntStream.range(1, 101).toArray(), s -> s.skip(0).limit(100), IntStream.range(1, 101).toArray());
+        exerciseOps(IntStream.range(1, 101).toArray(), s -> s.skip(0).limit(10), IntStream.range(1, 11).toArray());
+        exerciseOps(IntStream.range(1, 101).toArray(), s -> s.skip(0).limit(0), EMPTY_INT_ARRAY);
+        exerciseOps(IntStream.range(1, 101).toArray(), s -> s.skip(10).limit(100), IntStream.range(11, 101).toArray());
+        exerciseOps(IntStream.range(1, 101).toArray(), s -> s.skip(10).limit(10), IntStream.range(11, 21).toArray());
+        exerciseOps(IntStream.range(1, 101).toArray(), s -> s.skip(10).limit(0), EMPTY_INT_ARRAY);
+        exerciseOps(IntStream.range(1, 101).toArray(), s -> s.skip(100).limit(100), EMPTY_INT_ARRAY);
+        exerciseOps(IntStream.range(1, 101).toArray(), s -> s.skip(100).limit(10), EMPTY_INT_ARRAY);
+        exerciseOps(IntStream.range(1, 101).toArray(), s -> s.skip(100).limit(0), EMPTY_INT_ARRAY);
+        exerciseOps(IntStream.range(1, 101).toArray(), s -> s.skip(200).limit(100), EMPTY_INT_ARRAY);
+        exerciseOps(IntStream.range(1, 101).toArray(), s -> s.skip(200).limit(10), EMPTY_INT_ARRAY);
+        exerciseOps(IntStream.range(1, 101).toArray(), s -> s.skip(200).limit(0), EMPTY_INT_ARRAY);
     }
 
     private int sliceSize(int dataSize, int skip, int limit) {
@@ -146,10 +128,10 @@ public class IntSliceOpTest extends OpTestCase {
 
         for (int s : skips) {
             setContext("skip", s);
-            Collection<Integer> sr = exerciseOps(data, st -> st.substream(s));
+            Collection<Integer> sr = exerciseOps(data, st -> st.skip(s));
             assertEquals(sr.size(), sliceSize(data.size(), s));
 
-            sr = exerciseOps(data, st -> st.substream(s).substream(s / 2));
+            sr = exerciseOps(data, st -> st.skip(s).skip(s / 2));
             assertEquals(sr.size(), sliceSize(sliceSize(data.size(), s), s / 2));
         }
     }
@@ -163,10 +145,10 @@ public class IntSliceOpTest extends OpTestCase {
             setContext("skip", s);
             for (int limit : limits) {
                 setContext("limit", limit);
-                Collection<Integer> sr = exerciseOps(data, st -> st.substream(s).limit(limit));
+                Collection<Integer> sr = exerciseOps(data, st -> st.skip(s).limit(limit));
                 assertEquals(sr.size(), sliceSize(sliceSize(data.size(), s), 0, limit));
 
-                sr = exerciseOps(data, st -> st.substream(s, limit+s));
+                sr = exerciseOps(data, st -> st.skip(s).limit(limit));
                 assertEquals(sr.size(), sliceSize(data.size(), s, limit));
             }
         }
@@ -204,7 +186,7 @@ public class IntSliceOpTest extends OpTestCase {
     }
 
     public void testSkipParallel() {
-        int[] l = IntStream.range(1, 1001).parallel().substream(200).limit(200).sequential().toArray();
+        int[] l = IntStream.range(1, 1001).parallel().skip(200).limit(200).sequential().toArray();
         assertEquals(l.length, 200);
         assertEquals(l[l.length - 1], 400);
     }

test/java/util/stream/test/org/openjdk/tests/java/util/stream/SliceOpTest.java

@@ -50,27 +50,27 @@ import static java.util.stream.LambdaTestHelpers.*;
 public class SliceOpTest extends OpTestCase {
 
     public void testSkip() {
-        assertCountSum(countTo(0).stream().substream(0), 0, 0);
-        assertCountSum(countTo(0).stream().substream(4), 0, 0);
-        assertCountSum(countTo(4).stream().substream(4), 0, 0);
-        assertCountSum(countTo(4).stream().substream(2), 2, 7);
-        assertCountSum(countTo(4).stream().substream(0), 4, 10);
+        assertCountSum(countTo(0).stream().skip(0), 0, 0);
+        assertCountSum(countTo(0).stream().skip(4), 0, 0);
+        assertCountSum(countTo(4).stream().skip(4), 0, 0);
+        assertCountSum(countTo(4).stream().skip(2), 2, 7);
+        assertCountSum(countTo(4).stream().skip(0), 4, 10);
 
-        assertCountSum(countTo(0).parallelStream().substream(0), 0, 0);
-        assertCountSum(countTo(0).parallelStream().substream(4), 0, 0);
-        assertCountSum(countTo(4).parallelStream().substream(4), 0, 0);
-        assertCountSum(countTo(4).parallelStream().substream(2), 2, 7);
-        assertCountSum(countTo(4).parallelStream().substream(0), 4, 10);
+        assertCountSum(countTo(0).parallelStream().skip(0), 0, 0);
+        assertCountSum(countTo(0).parallelStream().skip(4), 0, 0);
+        assertCountSum(countTo(4).parallelStream().skip(4), 0, 0);
+        assertCountSum(countTo(4).parallelStream().skip(2), 2, 7);
+        assertCountSum(countTo(4).parallelStream().skip(0), 4, 10);
 
-        exerciseOps(Collections.emptyList(), s -> s.substream(0), Collections.emptyList());
-        exerciseOps(Collections.emptyList(), s -> s.substream(10), Collections.emptyList());
+        exerciseOps(Collections.emptyList(), s -> s.skip(0), Collections.emptyList());
+        exerciseOps(Collections.emptyList(), s -> s.skip(10), Collections.emptyList());
 
-        exerciseOps(countTo(1), s -> s.substream(0), countTo(1));
-        exerciseOps(countTo(1), s -> s.substream(1), Collections.emptyList());
-        exerciseOps(countTo(100), s -> s.substream(0), countTo(100));
-        exerciseOps(countTo(100), s -> s.substream(10), range(11, 100));
-        exerciseOps(countTo(100), s -> s.substream(100), Collections.emptyList());
-        exerciseOps(countTo(100), s -> s.substream(200), Collections.emptyList());
+        exerciseOps(countTo(1), s -> s.skip(0), countTo(1));
+        exerciseOps(countTo(1), s -> s.skip(1), Collections.emptyList());
+        exerciseOps(countTo(100), s -> s.skip(0), countTo(100));
+        exerciseOps(countTo(100), s -> s.skip(10), range(11, 100));
+        exerciseOps(countTo(100), s -> s.skip(100), Collections.emptyList());
+        exerciseOps(countTo(100), s -> s.skip(200), Collections.emptyList());
     }
 
     public void testLimit() {
@@ -97,43 +97,43 @@ public class SliceOpTest extends OpTestCase {
     }
 
     public void testSkipLimit() {
-        exerciseOps(Collections.emptyList(), s -> s.substream(0).limit(0), Collections.emptyList());
-        exerciseOps(Collections.emptyList(), s -> s.substream(0).limit(10), Collections.emptyList());
-        exerciseOps(Collections.emptyList(), s -> s.substream(10).limit(0), Collections.emptyList());
-        exerciseOps(Collections.emptyList(), s -> s.substream(10).limit(10), Collections.emptyList());
-
-        exerciseOps(countTo(100), s -> s.substream(0).limit(100), countTo(100));
-        exerciseOps(countTo(100), s -> s.substream(0).limit(10), countTo(10));
-        exerciseOps(countTo(100), s -> s.substream(0).limit(0), Collections.emptyList());
-        exerciseOps(countTo(100), s -> s.substream(10).limit(100), range(11, 100));
-        exerciseOps(countTo(100), s -> s.substream(10).limit(10), range(11, 20));
-        exerciseOps(countTo(100), s -> s.substream(10).limit(0), Collections.emptyList());
-        exerciseOps(countTo(100), s -> s.substream(100).limit(100), Collections.emptyList());
-        exerciseOps(countTo(100), s -> s.substream(100).limit(10), Collections.emptyList());
-        exerciseOps(countTo(100), s -> s.substream(100).limit(0), Collections.emptyList());
-        exerciseOps(countTo(100), s -> s.substream(200).limit(100), Collections.emptyList());
-        exerciseOps(countTo(100), s -> s.substream(200).limit(10), Collections.emptyList());
-        exerciseOps(countTo(100), s -> s.substream(200).limit(0), Collections.emptyList());
+        exerciseOps(Collections.emptyList(), s -> s.skip(0).limit(0), Collections.emptyList());
+        exerciseOps(Collections.emptyList(), s -> s.skip(0).limit(10), Collections.emptyList());
+        exerciseOps(Collections.emptyList(), s -> s.skip(10).limit(0), Collections.emptyList());
+        exerciseOps(Collections.emptyList(), s -> s.skip(10).limit(10), Collections.emptyList());
+
+        exerciseOps(countTo(100), s -> s.skip(0).limit(100), countTo(100));
+        exerciseOps(countTo(100), s -> s.skip(0).limit(10), countTo(10));
+        exerciseOps(countTo(100), s -> s.skip(0).limit(0), Collections.emptyList());
+        exerciseOps(countTo(100), s -> s.skip(10).limit(100), range(11, 100));
+        exerciseOps(countTo(100), s -> s.skip(10).limit(10), range(11, 20));
+        exerciseOps(countTo(100), s -> s.skip(10).limit(0), Collections.emptyList());
+        exerciseOps(countTo(100), s -> s.skip(100).limit(100), Collections.emptyList());
+        exerciseOps(countTo(100), s -> s.skip(100).limit(10), Collections.emptyList());
+        exerciseOps(countTo(100), s -> s.skip(100).limit(0), Collections.emptyList());
+        exerciseOps(countTo(100), s -> s.skip(200).limit(100), Collections.emptyList());
+        exerciseOps(countTo(100), s -> s.skip(200).limit(10), Collections.emptyList());
+        exerciseOps(countTo(100), s -> s.skip(200).limit(0), Collections.emptyList());
     }
 
     public void testSlice() {
-        exerciseOps(Collections.emptyList(), s -> s.substream(0, 0), Collections.emptyList());
-        exerciseOps(Collections.emptyList(), s -> s.substream(0, 10), Collections.emptyList());
-        exerciseOps(Collections.emptyList(), s -> s.substream(10, 10), Collections.emptyList());
-        exerciseOps(Collections.emptyList(), s -> s.substream(10, 20), Collections.emptyList());
-
-        exerciseOps(countTo(100), s -> s.substream(0, 100), countTo(100));
-        exerciseOps(countTo(100), s -> s.substream(0, 10), countTo(10));
-        exerciseOps(countTo(100), s -> s.substream(0, 0), Collections.emptyList());
-        exerciseOps(countTo(100), s -> s.substream(10, 110), range(11, 100));
-        exerciseOps(countTo(100), s -> s.substream(10, 20), range(11, 20));
-        exerciseOps(countTo(100), s -> s.substream(10, 10), Collections.emptyList());
-        exerciseOps(countTo(100), s -> s.substream(100, 200), Collections.emptyList());
-        exerciseOps(countTo(100), s -> s.substream(100, 110), Collections.emptyList());
-        exerciseOps(countTo(100), s -> s.substream(100, 100), Collections.emptyList());
-        exerciseOps(countTo(100), s -> s.substream(200, 300), Collections.emptyList());
-        exerciseOps(countTo(100), s -> s.substream(200, 210), Collections.emptyList());
-        exerciseOps(countTo(100), s -> s.substream(200, 200), Collections.emptyList());
+        exerciseOps(Collections.emptyList(), s -> s.skip(0).limit(0), Collections.emptyList());
+        exerciseOps(Collections.emptyList(), s -> s.skip(0).limit(10), Collections.emptyList());
+        exerciseOps(Collections.emptyList(), s -> s.skip(10).limit(10), Collections.emptyList());
+        exerciseOps(Collections.emptyList(), s -> s.skip(10).limit(20), Collections.emptyList());
+
+        exerciseOps(countTo(100), s -> s.skip(0).limit(100), countTo(100));
+        exerciseOps(countTo(100), s -> s.skip(0).limit(10), countTo(10));
+        exerciseOps(countTo(100), s -> s.skip(0).limit(0), Collections.emptyList());
+        exerciseOps(countTo(100), s -> s.skip(10).limit(100), range(11, 100));
+        exerciseOps(countTo(100), s -> s.skip(10).limit(10), range(11, 20));
+        exerciseOps(countTo(100), s -> s.skip(10).limit(0), Collections.emptyList());
+        exerciseOps(countTo(100), s -> s.skip(100).limit(100), Collections.emptyList());
+        exerciseOps(countTo(100), s -> s.skip(100).limit(10), Collections.emptyList());
+        exerciseOps(countTo(100), s -> s.skip(100).limit(0), Collections.emptyList());
+        exerciseOps(countTo(100), s -> s.skip(200).limit(100), Collections.emptyList());
+        exerciseOps(countTo(100), s -> s.skip(200).limit(10), Collections.emptyList());
+        exerciseOps(countTo(100), s -> s.skip(200).limit(0), Collections.emptyList());
     }
 
     private int sliceSize(int dataSize, int skip, int limit) {
@@ -156,17 +156,17 @@ public class SliceOpTest extends OpTestCase {
             setContext("skip", s);
             testSliceMulti(data,
                            sliceSize(data.size(), s),
-                           st -> st.substream(s),
-                           st -> st.substream(s),
-                           st -> st.substream(s),
-                           st -> st.substream(s));
+                           st -> st.skip(s),
+                           st -> st.skip(s),
+                           st -> st.skip(s),
+                           st -> st.skip(s));
 
             testSliceMulti(data,
                            sliceSize(sliceSize(data.size(), s), s/2),
-                           st -> st.substream(s).substream(s / 2),
-                           st -> st.substream(s).substream(s / 2),
-                           st -> st.substream(s).substream(s / 2),
-                           st -> st.substream(s).substream(s / 2));
+                           st -> st.skip(s).skip(s / 2),
+                           st -> st.skip(s).skip(s / 2),
+                           st -> st.skip(s).skip(s / 2),
+                           st -> st.skip(s).skip(s / 2));
         }
     }
 
@@ -182,17 +182,10 @@ public class SliceOpTest extends OpTestCase {
                 setContext("limit", l);
                 testSliceMulti(data,
                                sliceSize(sliceSize(data.size(), s), 0, l),
-                               st -> st.substream(s).limit(l),
-                               st -> st.substream(s).limit(l),
-                               st -> st.substream(s).limit(l),
-                               st -> st.substream(s).limit(l));
-
-                testSliceMulti(data,
-                               sliceSize(data.size(), s, l),
-                                st -> st.substream(s, l+s),
-                                st -> st.substream(s, l+s),
-                                st -> st.substream(s, l+s),
-                                st -> st.substream(s, l+s));
+                               st -> st.skip(s).limit(l),
+                               st -> st.skip(s).limit(l),
+                               st -> st.skip(s).limit(l),
+                               st -> st.skip(s).limit(l));
             }
         }
     }