| /* |
| * Copyright (c) 2015, 2016, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| package jdk.incubator.http.internal.hpack; |
| |
| import java.nio.ByteBuffer; |
| import java.util.*; |
| import java.util.function.Consumer; |
| import java.util.function.Function; |
| import java.util.function.Supplier; |
| |
| import static java.nio.ByteBuffer.allocate; |
| |
| public final class BuffersTestingKit { |
| |
| /** |
| * Relocates a {@code [position, limit)} region of the given buffer to |
| * corresponding region in a new buffer starting with provided {@code |
| * newPosition}. |
| * |
| * <p> Might be useful to make sure ByteBuffer's users do not rely on any |
| * absolute positions, but solely on what's reported by position(), limit(). |
| * |
| * <p> The contents between the given buffer and the returned one are not |
| * shared. |
| */ |
| public static ByteBuffer relocate(ByteBuffer buffer, int newPosition, |
| int newCapacity) { |
| int oldPosition = buffer.position(); |
| int oldLimit = buffer.limit(); |
| |
| if (newPosition + oldLimit - oldPosition > newCapacity) { |
| throw new IllegalArgumentException(); |
| } |
| |
| ByteBuffer result; |
| if (buffer.isDirect()) { |
| result = ByteBuffer.allocateDirect(newCapacity); |
| } else { |
| result = allocate(newCapacity); |
| } |
| |
| result.position(newPosition); |
| result.put(buffer).limit(result.position()).position(newPosition); |
| buffer.position(oldPosition); |
| |
| if (buffer.isReadOnly()) { |
| return result.asReadOnlyBuffer(); |
| } |
| return result; |
| } |
| |
| public static Iterable<? extends ByteBuffer> relocateBuffers( |
| Iterable<? extends ByteBuffer> source) { |
| return () -> |
| new Iterator<ByteBuffer>() { |
| |
| private final Iterator<? extends ByteBuffer> it = source.iterator(); |
| |
| @Override |
| public boolean hasNext() { |
| return it.hasNext(); |
| } |
| |
| @Override |
| public ByteBuffer next() { |
| ByteBuffer buf = it.next(); |
| int remaining = buf.remaining(); |
| int newCapacity = remaining + random.nextInt(17); |
| int newPosition = random.nextInt(newCapacity - remaining + 1); |
| return relocate(buf, newPosition, newCapacity); |
| } |
| }; |
| } |
| |
| // TODO: not always of size 0 (it's fine for buffer to report !b.hasRemaining()) |
| public static Iterable<? extends ByteBuffer> injectEmptyBuffers( |
| Iterable<? extends ByteBuffer> source) { |
| return injectEmptyBuffers(source, () -> allocate(0)); |
| } |
| |
| public static Iterable<? extends ByteBuffer> injectEmptyBuffers( |
| Iterable<? extends ByteBuffer> source, |
| Supplier<? extends ByteBuffer> emptyBufferFactory) { |
| |
| return () -> |
| new Iterator<ByteBuffer>() { |
| |
| private final Iterator<? extends ByteBuffer> it = source.iterator(); |
| private ByteBuffer next = calculateNext(); |
| |
| private ByteBuffer calculateNext() { |
| if (random.nextBoolean()) { |
| return emptyBufferFactory.get(); |
| } else if (it.hasNext()) { |
| return it.next(); |
| } else { |
| return null; |
| } |
| } |
| |
| @Override |
| public boolean hasNext() { |
| return next != null; |
| } |
| |
| @Override |
| public ByteBuffer next() { |
| if (!hasNext()) { |
| throw new NoSuchElementException(); |
| } |
| ByteBuffer next = this.next; |
| this.next = calculateNext(); |
| return next; |
| } |
| }; |
| } |
| |
| public static ByteBuffer concat(Iterable<? extends ByteBuffer> split) { |
| return concat(split, ByteBuffer::allocate); |
| } |
| |
| public static ByteBuffer concat(Iterable<? extends ByteBuffer> split, |
| Function<? super Integer, ? extends ByteBuffer> concatBufferFactory) { |
| int size = 0; |
| for (ByteBuffer bb : split) { |
| size += bb.remaining(); |
| } |
| |
| ByteBuffer result = concatBufferFactory.apply(size); |
| for (ByteBuffer bb : split) { |
| result.put(bb); |
| } |
| |
| result.flip(); |
| return result; |
| } |
| |
| public static void forEachSplit(ByteBuffer bb, |
| Consumer<? super Iterable<? extends ByteBuffer>> action) { |
| forEachSplit(bb.remaining(), |
| (lengths) -> { |
| int end = bb.position(); |
| List<ByteBuffer> buffers = new LinkedList<>(); |
| for (int len : lengths) { |
| ByteBuffer d = bb.duplicate(); |
| d.position(end); |
| d.limit(end + len); |
| end += len; |
| buffers.add(d); |
| } |
| action.accept(buffers); |
| }); |
| } |
| |
| private static void forEachSplit(int n, Consumer<? super Iterable<? extends Integer>> action) { |
| forEachSplit(n, new Stack<>(), action); |
| } |
| |
| private static void forEachSplit(int n, Stack<Integer> path, |
| Consumer<? super Iterable<? extends Integer>> action) { |
| if (n == 0) { |
| action.accept(path); |
| } else { |
| for (int i = 1; i <= n; i++) { |
| path.push(i); |
| forEachSplit(n - i, path, action); |
| path.pop(); |
| } |
| } |
| } |
| |
| private static final Random random = new Random(); |
| |
| private BuffersTestingKit() { |
| throw new InternalError(); |
| } |
| |
| // public static void main(String[] args) { |
| // |
| // List<ByteBuffer> buffers = Arrays.asList( |
| // (ByteBuffer) allocate(3).position(1).limit(2), |
| // allocate(0), |
| // allocate(7)); |
| // |
| // Iterable<? extends ByteBuffer> buf = relocateBuffers(injectEmptyBuffers(buffers)); |
| // List<ByteBuffer> result = new ArrayList<>(); |
| // buf.forEach(result::add); |
| // System.out.println(result); |
| // } |
| } |