content: /*
   * 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.test.espresso.web.assertion;
  
  import android.os.Binder;
  import androidx.annotation.NonNull;
  import androidx.test.espresso.remote.Converter;
  import com.google.protobuf.ByteString;
  import java.io.IOException;
  import java.io.StringWriter;
  import javax.xml.transform.Transformer;
  import javax.xml.transform.TransformerException;
  import javax.xml.transform.TransformerFactory;
  import javax.xml.transform.dom.DOMSource;
  import javax.xml.transform.stream.StreamResult;
  import org.w3c.dom.Document;
  
  /**
   * Converts a type {@link Document} into its {@link ByteString} representation.
   *
   * <p>This class uses {@link
   * androidx.test.espresso.web.assertion.CompressorDecompressor.GZIPCompressor} to reduce the
   * size of the document as much as possible to avoid hitting the {@link Binder} transaction limit.
   */
  final class DocumentToByteStringConverter implements Converter<Document, ByteString> {
    private static byte[] compressDocument(String document) throws IOException {
      return CompressorDecompressor.compress(document.getBytes());
    }
  
    /**
     * Convert an object of type {@link Document} into its {@link ByteString} representation.
     *
     * @param document to convert into a {@link ByteString}
     */
    @Override
    public ByteString convert(@NonNull Document document) {
      try {
        DOMSource docSource = new DOMSource(document);
        Transformer transformer = TransformerFactory.newInstance().newTransformer();
        StringWriter writer = new StringWriter();
        StreamResult streamer = new StreamResult(writer);
        transformer.transform(docSource, streamer);
        return ByteString.copyFrom(compressDocument(writer.toString()));
      } catch (TransformerException te) {
        throw new RuntimeException("Could not convert!!!", te);
      } catch (IOException ioe) {
        throw new RuntimeException("Could not convert!!!", ioe);
      }
    }
  }
  