/**
    * Logback: the reliable, generic, fast and flexible logging framework.
    * Copyright (C) 1999-2011, QOS.ch. All rights reserved.
    *
    * This program and the accompanying materials are dual-licensed under
    * either the terms of the Eclipse Public License v1.0 as published by
    * the Eclipse Foundation
    *
    *   or (per the licensee's choosing)
   *
   * under the terms of the GNU Lesser General Public License version 2.1
   * as published by the Free Software Foundation.
   */
  package ch.qos.logback.access.servlet;
  
  import java.io.ByteArrayOutputStream;
  import java.io.IOException;
  
  import javax.servlet.ServletOutputStream;
  import javax.servlet.ServletResponse;
  
  public class TeeServletOutputStream extends ServletOutputStream {
  
    final ServletOutputStream underlyingStream;
    final ByteArrayOutputStream baosCopy;
  
    TeeServletOutputStream(ServletResponse httpServletResponse)
        throws IOException {
      // System.out.println("TeeServletOutputStream.constructor() called");
      this.underlyingStream = httpServletResponse.getOutputStream();
      baosCopy = new ByteArrayOutputStream();
    }
  
    byte[] getOutputStreamAsByteArray() {
      return baosCopy.toByteArray();
    }
  
    @Override
    public void write(int val) throws IOException {
      if (underlyingStream != null) {
        underlyingStream.write(val);
        baosCopy.write(val);
      }
    }
  
    @Override
    public void write(byte[] byteArray) throws IOException {
      if (underlyingStream == null) {
        return;
      }
      // System.out.println("WRITE TeeServletOutputStream.write(byte[]) called");
      write(byteArray, 0, byteArray.length);
    }
  
    @Override
    public void write(byte byteArray[], int offset, int length)
        throws IOException {
      if (underlyingStream == null) {
        return;
      }
      // System.out.println("WRITE TeeServletOutputStream.write(byte[], int, int)
      // called");
      // System.out.println(new String(byteArray, offset, length));
      underlyingStream.write(byteArray, offset, length);
      baosCopy.write(byteArray, offset, length);
    }
  
    @Override
    public void close() throws IOException {
      // System.out.println("CLOSE TeeServletOutputStream.close() called");
  
      // If the servlet accessing the stream is using a writer instead of
      // an OutputStream, it will probably call os.close() before calling
      // writer.close. Thus, the underlying output stream will be called
      // before the data sent to the writer could be flushed.
    }
  
  
    @Override
    public void flush() throws IOException {
      if (underlyingStream == null) {
        return;
      }
      // System.out.println("FLUSH TeeServletOutputStream.flush() called");
      underlyingStream.flush();
      baosCopy.flush();
    }
  }