| /* |
| * Copyright (c) 2012, 2018, 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. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * 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.jfr.internal; |
| |
| import java.io.FileNotFoundException; |
| import java.io.IOException; |
| import java.nio.ByteBuffer; |
| import java.nio.channels.FileChannel; |
| import java.nio.channels.ReadableByteChannel; |
| import java.util.ArrayList; |
| import java.util.Iterator; |
| import java.util.List; |
| |
| final class ChunksChannel implements ReadableByteChannel { |
| private final Iterator<RepositoryChunk> chunks; |
| private RepositoryChunk current; |
| private ReadableByteChannel channel; |
| |
| public ChunksChannel(List<RepositoryChunk> chunks) throws IOException { |
| if (chunks.isEmpty()) { |
| throw new FileNotFoundException("No chunks"); |
| } |
| List<RepositoryChunk> l = new ArrayList<>(chunks.size()); |
| for (RepositoryChunk c : chunks) { |
| c.use(); // keep alive while we're reading. |
| l.add(c); |
| } |
| this.chunks = l.iterator(); |
| nextChannel(); |
| } |
| |
| private boolean nextChunk() { |
| if (!chunks.hasNext()) { |
| return false; |
| } |
| current = chunks.next(); |
| return true; |
| } |
| |
| private boolean nextChannel() throws IOException { |
| if (!nextChunk()) { |
| return false; |
| } |
| |
| channel = current.newChannel(); |
| return true; |
| } |
| |
| @Override |
| public int read(ByteBuffer dst) throws IOException { |
| for (;;) { |
| if (channel != null) { |
| assert current != null; |
| int r = channel.read(dst); |
| if (r != -1) { |
| return r; |
| } |
| channel.close(); |
| current.release(); |
| channel = null; |
| current = null; |
| } |
| if (!nextChannel()) { |
| return -1; |
| } |
| } |
| } |
| |
| public long transferTo(FileChannel out) throws IOException { |
| long pos = 0; |
| for (;;) { |
| if (channel != null) { |
| assert current != null; |
| |
| long rem = current.getSize(); |
| |
| while (rem > 0) { |
| long n = Math.min(rem, 1024 * 1024); |
| long w = out.transferFrom(channel, pos, n); |
| pos += w; |
| rem -= w; |
| } |
| |
| channel.close(); |
| current.release(); |
| |
| channel = null; |
| current = null; |
| } |
| if (!nextChannel()) { |
| return pos; |
| } |
| } |
| } |
| |
| @Override |
| public void close() throws IOException { |
| if (channel != null) { |
| channel.close(); |
| channel = null; |
| } |
| while (current != null) { |
| current.release(); |
| current = null; |
| if (!nextChunk()) { |
| return; |
| } |
| } |
| } |
| |
| @Override |
| public boolean isOpen() { |
| return channel != null; |
| } |
| |
| @Override |
| @SuppressWarnings("deprecation") |
| protected void finalize() throws Throwable { |
| super.finalize(); |
| close(); |
| } |
| } |