CacheResponseWrapper.java

/*
 * Copyright 2003 Jayson Falkner (jayson@jspinsider.com)
 * This code is from "Servlets and JavaServer pages; the J2EE Web Tier",
 * http://www.jspbook.com. You may freely use the code both commercially
 * and non-commercially. If you like the code, please pick up a copy of
 * the book and help support the authors, development of more free code,
 * and the JSP/Servlet/J2EE community.
 */
package org.freehep.webutil.cache;

import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;

public class CacheResponseWrapper
        extends HttpServletResponseWrapper {
    protected HttpServletResponse origResponse = null;
    protected ServletOutputStream stream = null;
    protected PrintWriter writer = null;
    protected OutputStream cache = null;
    
    public CacheResponseWrapper(HttpServletResponse response,
            OutputStream cache) {
        super(response);
        origResponse = response;
        this.cache = cache;
    }
    
    public ServletOutputStream createOutputStream()
    throws IOException {
        return (new CacheResponseStream(origResponse, cache));
    }
    
    public void flushBuffer() throws IOException {
        stream.flush();
    }
    
    public ServletOutputStream getOutputStream()
    throws IOException {
        if (writer != null) {
            throw new IllegalStateException(
                    "getWriter() has already been called!");
        }
        
        if (stream == null)
            stream = createOutputStream();
        return (stream);
    }
    
    public PrintWriter getWriter() throws IOException {
        if (writer != null) {
            return (writer);
        }
        
        if (stream != null) {
            throw new IllegalStateException(
                    "getOutputStream() has already been called!");
        }
        
        stream = createOutputStream();
        writer = new PrintWriter(new OutputStreamWriter(stream, "UTF-8"));
        return (writer);
    }
}