| /* |
| * Copyright 2020 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package com.google.android.exoplayer2.extractor.jpeg; |
| |
| import static com.google.android.exoplayer2.util.Assertions.checkArgument; |
| |
| import com.google.android.exoplayer2.extractor.ExtractorInput; |
| import com.google.android.exoplayer2.extractor.ForwardingExtractorInput; |
| |
| /** |
| * An extractor input that wraps another extractor input and exposes data starting at a given start |
| * byte offset. |
| * |
| * <p>This is useful for reading data from a container that's concatenated after some prefix data |
| * but where the container's extractor doesn't handle a non-zero start offset (for example, because |
| * it seeks to absolute positions read from the container data). |
| */ |
| /* package */ final class StartOffsetExtractorInput extends ForwardingExtractorInput { |
| |
| private final long startOffset; |
| |
| /** |
| * Creates a new wrapper reading from the given start byte offset. |
| * |
| * @param input The extractor input to wrap. The reading position must be at or after the start |
| * offset, otherwise data could be read from before the start offset. |
| * @param startOffset The offset from which this extractor input provides data, in bytes. |
| * @throws IllegalArgumentException Thrown if the start offset is before the current reading |
| * position. |
| */ |
| public StartOffsetExtractorInput(ExtractorInput input, long startOffset) { |
| super(input); |
| checkArgument(input.getPosition() >= startOffset); |
| this.startOffset = startOffset; |
| } |
| |
| @Override |
| public long getPosition() { |
| return super.getPosition() - startOffset; |
| } |
| |
| @Override |
| public long getPeekPosition() { |
| return super.getPeekPosition() - startOffset; |
| } |
| |
| @Override |
| public long getLength() { |
| return super.getLength() - startOffset; |
| } |
| |
| @Override |
| public <E extends Throwable> void setRetryPosition(long position, E e) throws E { |
| super.setRetryPosition(position + startOffset, e); |
| } |
| } |