ServletResponseWrapperInclude.java :  » JBoss » richfaces-ui-3.3.2 » org » ajax4jsf » taglib » html » jsp » Java Open Source

/*
 * Copyright 1999,2004 The Apache Software Foundation.
 * 
 * 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 org.ajax4jsf.taglib.html.jsp;

import java.io.IOException;
import java.io.PrintWriter;
import java.util.Locale;

import javax.servlet.ServletOutputStream;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpServletResponseWrapper;
import javax.servlet.jsp.JspWriter;

import org.ajax4jsf.io.FastBufferOutputStream;



/**
 * ServletResponseWrapper used by the JSP 'include' action.
 * 
 * This wrapper response object is passed to RequestDispatcher.include(), so
 * that the output of the included resource is appended to that of the including
 * page.
 * 
 * @author Pierre Delisle
 */

public class ServletResponseWrapperInclude extends HttpServletResponseWrapper {

  /**
   * PrintWriter which appends to the JspWriter of the including page.
   */
  private PrintWriter _printWriter;
  
  private FastBufferOutputStream _bytes ;
  
  private ServletOutputStream _servletStream;

  private JspWriter _jspWriter;
  
  private boolean useWriter = false;
  
  private boolean useStream = false;

  public ServletResponseWrapperInclude(ServletResponse response,
      JspWriter jspWriter) {
    super((HttpServletResponse) response);
    this._printWriter = new PrintWriter(jspWriter);
    this._jspWriter = jspWriter;
  }

  /**
   * Returns a wrapper around the JspWriter of the including page.
   */
  public PrintWriter getWriter() throws IOException {
    if (useStream) {
      throw new IllegalStateException();
    }
    useWriter = true;
    return _printWriter;
  }

  public ServletOutputStream getOutputStream() throws IOException {
    if(useWriter){
      throw new IllegalStateException();
    }
    if (!useStream) {
      _bytes = new FastBufferOutputStream(getBufferSize());
      _servletStream = new ServletOutputStream(){

        /* (non-Javadoc)
         * @see java.io.OutputStream#flush()
         */
        public void flush() throws IOException {
          // TODO Auto-generated method stub
          super.flush();
        }

        /* (non-Javadoc)
         * @see java.io.OutputStream#write(byte[], int, int)
         */
        public void write(byte[] b, int off, int len) throws IOException {
          // TODO Auto-generated method stub
          _bytes.write(b, off, len);
        }

        /* (non-Javadoc)
         * @see java.io.OutputStream#write(byte[])
         */
        public void write(byte[] b) throws IOException {
          // TODO Auto-generated method stub
          _bytes.write(b);
        }

        /* (non-Javadoc)
         * @see java.io.OutputStream#write(int)
         */
        public void write(int b) throws IOException {
          _bytes.write(b);          
        }
        
      };
      useStream = true;
    }
    return _servletStream;
  }

  /**
   * Clears the output buffer of the JspWriter associated with the including
   * page.
   */
  public void resetBuffer() {
    try {
      _jspWriter.clearBuffer();
      useWriter = false;
      useStream = false;
      _bytes = null;
    } catch (IOException ioe) {
    }
  }
  
  public void reset() {
    // TODO Auto-generated method stub
    resetBuffer();
  }
  
  public void flushBuffer() throws IOException {
    if (useStream) {
      // TODO - detect encoding ?
      _bytes.writeTo(_jspWriter, getCharacterEncoding());
      _bytes = new FastBufferOutputStream(getBufferSize());
    }
  }
  
  // Override ignored methods.
  public void setBufferSize(int arg0) {
  }
  
  public void setContentLength(int arg0) {
  }
  public void setContentType(String arg0) {
  }
  public void setStatus(int arg0) {
  }
  public void setLocale(Locale arg0) {
  }
  public void sendRedirect(String arg0) throws IOException {
    throw new IllegalStateException();
  }
//  public void setStatus(int arg0, String arg1) {
//  }
  
}