1 /* 2 * Copyright 2012 Sebastian Annies, Hamburg 3 * 4 * Licensed under the Apache License, Version 2.0 (the License); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an AS IS BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 package com.coremedia.iso; 17 18 import java.io.EOFException; 19 import java.io.IOException; 20 import java.nio.ByteBuffer; 21 import java.nio.channels.FileChannel; 22 import java.nio.channels.ReadableByteChannel; 23 import java.nio.channels.SelectionKey; 24 import java.nio.channels.WritableByteChannel; 25 26 import static com.googlecode.mp4parser.util.CastUtils.l2i; 27 28 29 public class ChannelHelper { readFully(final ReadableByteChannel channel, long size)30 public static ByteBuffer readFully(final ReadableByteChannel channel, long size) throws IOException { 31 32 if (channel instanceof FileChannel && size > 1024 * 1024) { 33 ByteBuffer bb = ((FileChannel) channel).map(FileChannel.MapMode.READ_ONLY, ((FileChannel) channel).position(), size); 34 ((FileChannel) channel).position(((FileChannel) channel).position() + size); 35 return bb; 36 } else { 37 ByteBuffer buf = ByteBuffer.allocate(l2i(size)); 38 readFully(channel, buf, buf.limit()); 39 buf.rewind(); 40 assert buf.limit() == size; 41 42 return buf; 43 } 44 45 } 46 47 readFully(final ReadableByteChannel channel, final ByteBuffer buf)48 public static void readFully(final ReadableByteChannel channel, final ByteBuffer buf) 49 throws IOException { 50 readFully(channel, buf, buf.remaining()); 51 } 52 readFully(final ReadableByteChannel channel, final ByteBuffer buf, final int length)53 public static int readFully(final ReadableByteChannel channel, final ByteBuffer buf, final int length) 54 throws IOException { 55 int n, count = 0; 56 while (-1 != (n = channel.read(buf))) { 57 count += n; 58 if (count == length) { 59 break; 60 } 61 } 62 if (n == -1) { 63 throw new EOFException("End of file. No more boxes."); 64 } 65 return count; 66 } 67 68 writeFully(final WritableByteChannel channel, final ByteBuffer buf)69 public static void writeFully(final WritableByteChannel channel, final ByteBuffer buf) 70 throws IOException { 71 do { 72 int written = channel.write(buf); 73 if (written < 0) { 74 throw new EOFException(); 75 } 76 } while (buf.hasRemaining()); 77 } 78 79 close(SelectionKey key)80 public static void close(SelectionKey key) { 81 try { 82 key.channel().close(); 83 } catch (IOException e) { 84 // nop 85 } 86 87 } 88 89 90 }