import com.google.android.exoplayer.upstream.Loader; //导入依赖的package包/类
@Override
public boolean prepare(long positionUs) {
  Assertions.checkState(state == STATE_INITIALIZED || state == STATE_PREPARED);
  if (state == STATE_PREPARED) {
    return true;
  }
  loader = new Loader("Loader:" + chunkSource.getTrackInfo().mimeType);
  state = STATE_PREPARED;
  return true;
}
 

import com.google.android.exoplayer.upstream.Loader; //导入依赖的package包/类
public SingleFetchHelper(UriLoadable<T> singleUseLoadable, Looper callbackLooper,
    ManifestCallback<T> wrappedCallback) {
  this.singleUseLoadable = singleUseLoadable;
  this.callbackLooper = callbackLooper;
  this.wrappedCallback = wrappedCallback;
  singleUseLoader = new Loader("manifestLoader:single");
}
 

import com.google.android.exoplayer.upstream.Loader; //导入依赖的package包/类
@Override
public boolean prepare(long positionUs) {
  Assertions.checkState(state == STATE_INITIALIZED || state == STATE_PREPARED);
  if (state == STATE_PREPARED) {
    return true;
  } else if (!chunkSource.prepare()) {
    return false;
  }
  if (chunkSource.getTrackCount() > 0) {
    loader = new Loader("Loader:" + chunkSource.getFormat(0).mimeType);
  }
  state = STATE_PREPARED;
  return true;
}
 

import com.google.android.exoplayer.upstream.Loader; //导入依赖的package包/类
@Override
public boolean prepare() {
  Assertions.checkState(state == STATE_UNPREPARED);
  loader = new Loader("Loader:" + chunkSource.getTrackInfo().mimeType);
  state = STATE_PREPARED;
  return true;
}
 

import com.google.android.exoplayer.upstream.Loader; //导入依赖的package包/类
@Override
public boolean prepare() {
  Assertions.checkState(state == STATE_UNPREPARED);
  loader = new Loader("Loader:" + chunkSource.getTrackInfo().mimeType, this);
  state = STATE_PREPARED;
  return true;
}
 

import com.google.android.exoplayer.upstream.Loader; //导入依赖的package包/类
private void resolveHttp(UriLoadable.Parser<Long> parser) {
  singleUseLoader = new Loader("utctiming");
  singleUseLoadable = new UriLoadable<>(timingElement.value, uriDataSource, parser);
  singleUseLoader.startLoading(singleUseLoadable, this);
}
 

import com.google.android.exoplayer.upstream.Loader; //导入依赖的package包/类
public SingleFetchHelper(Looper callbackLooper, ManifestCallback<T> wrappedCallback) {
  this.callbackLooper = callbackLooper;
  this.wrappedCallback = wrappedCallback;
  singleUseLoader = new Loader("manifestLoader:single");
  singleUseLoadable = new ManifestLoadable();
}