content: /*
   * Licensed to the Apache Software Foundation (ASF) under one
   * or more contributor license agreements.  See the NOTICE file
   * distributed with this work for additional information
   * regarding copyright ownership.  The ASF licenses this file
   * to you 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 org.apache.asterix.external.input.stream;
  
  import java.io.DataOutput;
  import java.io.IOException;
  import java.io.OutputStream;
  
  import org.apache.asterix.dataflow.data.nontagged.serde.AStringSerializerDeserializer;
  import org.apache.asterix.external.util.ExternalDataConstants;
  import org.apache.hyracks.data.std.util.ByteArrayAccessibleInputStream;
  
  /**
   * Writes modified UTF-8 string format to {@link StandardUTF8ToModifiedUTF8OutputStream#out}
   * from standard UTF-8 string format.
   */
  public class StandardUTF8ToModifiedUTF8OutputStream extends OutputStream {
      private static final byte[] EMPTY = new byte[0];
      private final AStringSerializerDeserializer stringSerDer;
      private final ResettableUTF8InputStreamReader reader;
      private final char[] inputBuffer;
      private char[] appendBuffer;
      private DataOutput out;
  
      public StandardUTF8ToModifiedUTF8OutputStream(AStringSerializerDeserializer stringSerDer) {
          this.stringSerDer = stringSerDer;
          reader = new ResettableUTF8InputStreamReader(new ByteArrayAccessibleInputStream(EMPTY, 0, 0));
          inputBuffer = new char[ExternalDataConstants.DEFAULT_BUFFER_SIZE];
          appendBuffer = new char[ExternalDataConstants.DEFAULT_BUFFER_SIZE];
      }
  
      @Override
      public void write(int b) throws IOException {
          throw new UnsupportedOperationException();
      }
  
      @Override
      public void write(byte[] b) throws IOException {
          write(b, 0, b.length);
      }
  
      @Override
      public void write(byte[] b, int off, int len) throws IOException {
          reader.prepareNextRead(b, off, len);
          int numOfChars = reader.read(inputBuffer);
          int length = 0;
          while (numOfChars > 0) {
              appendBuffer = append(inputBuffer, appendBuffer, length, numOfChars);
              length += numOfChars;
              numOfChars = reader.read(inputBuffer);
          }
          stringSerDer.serialize(appendBuffer, 0, length, out);
      }
  
      public void setDataOutput(DataOutput out) {
          this.out = out;
      }
  
      private static char[] append(char[] src, char[] dest, int offset, int length) {
          char[] destBuf = dest;
          if (offset + length > dest.length) {
              char[] newDestBuffer = new char[dest.length * 2];
              System.arraycopy(destBuf, 0, newDestBuffer, 0, offset);
              destBuf = newDestBuffer;
          }
          System.arraycopy(src, 0, destBuf, offset, length);
          return destBuf;
      }
  
      private static class ResettableUTF8InputStreamReader extends AsterixInputStreamReader {
          private final ByteArrayAccessibleInputStream inByte;
  
          public ResettableUTF8InputStreamReader(ByteArrayAccessibleInputStream inByte) {
              super(new BasicInputStream(inByte), ExternalDataConstants.DEFAULT_BUFFER_SIZE);
              this.inByte = inByte;
          }
  
          //Rewind the reader after setting the byte array
          public void prepareNextRead(byte[] b, int off, int len) {
              inByte.setContent(b, off, len);
              done = false;
              remaining = false;
              byteBuffer.flip();
              charBuffer.flip();
          }
  
      }
  }
  