TeeDataSource.java
/*
* Copyright (C) 2016 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 androidx.media3.datasource;
import android.net.Uri;
import androidx.annotation.Nullable;
import androidx.media3.common.C;
import androidx.media3.common.util.Assertions;
import androidx.media3.common.util.UnstableApi;
import java.io.IOException;
import java.util.List;
import java.util.Map;
/** Tees data into a {@link DataSink} as the data is read. */
@UnstableApi
public final class TeeDataSource implements DataSource {
private final DataSource upstream;
private final DataSink dataSink;
private boolean dataSinkNeedsClosing;
private long bytesRemaining;
/**
* @param upstream The upstream {@link DataSource}.
* @param dataSink The {@link DataSink} into which data is written.
*/
public TeeDataSource(DataSource upstream, DataSink dataSink) {
this.upstream = Assertions.checkNotNull(upstream);
this.dataSink = Assertions.checkNotNull(dataSink);
}
@Override
public void addTransferListener(TransferListener transferListener) {
Assertions.checkNotNull(transferListener);
upstream.addTransferListener(transferListener);
}
@Override
public long open(DataSpec dataSpec) throws IOException {
bytesRemaining = upstream.open(dataSpec);
if (bytesRemaining == 0) {
return 0;
}
if (dataSpec.length == C.LENGTH_UNSET && bytesRemaining != C.LENGTH_UNSET) {
// Reconstruct dataSpec in order to provide the resolved length to the sink.
dataSpec = dataSpec.subrange(0, bytesRemaining);
}
dataSinkNeedsClosing = true;
dataSink.open(dataSpec);
return bytesRemaining;
}
@Override
public int read(byte[] buffer, int offset, int length) throws IOException {
if (bytesRemaining == 0) {
return C.RESULT_END_OF_INPUT;
}
int bytesRead = upstream.read(buffer, offset, length);
if (bytesRead > 0) {
// TODO: Consider continuing even if writes to the sink fail.
dataSink.write(buffer, offset, bytesRead);
if (bytesRemaining != C.LENGTH_UNSET) {
bytesRemaining -= bytesRead;
}
}
return bytesRead;
}
@Override
@Nullable
public Uri getUri() {
return upstream.getUri();
}
@Override
public Map<String, List<String>> getResponseHeaders() {
return upstream.getResponseHeaders();
}
@Override
public void close() throws IOException {
try {
upstream.close();
} finally {
if (dataSinkNeedsClosing) {
dataSinkNeedsClosing = false;
dataSink.close();
}
}
}
}