DO NOT REPLY [Bug 3941] New: - PrinWriter.flush() HttpServletResponse.flushBuffer() do not work

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http://nagoya.apache.org/bugzilla/show_bug.cgi?id=3941

PrinWriter.flush() HttpServletResponse.flushBuffer() do not work

           Summary: PrinWriter.flush() HttpServletResponse.flushBuffer() do
                    not work
           Product: Tomcat 4
           Version: 4.0 Release Candidate 2
          Platform: PC
        OS/Version: Linux
            Status: NEW
          Severity: Normal
          Priority: Other
         Component: Unknown
        AssignedTo: tomcat-dev@jakarta.apache.org
        ReportedBy: a.djaoui@rl.ac.uk


Flushing of buffered output from a servlet to a client does not work as shown in  
the following Servlet code and Clinet code. This problem only occured in Tomcat 
4 where the output only occures after closing the PrintWriter. The flushing 
works fine with Tomcat 3.2.3 for both the Prinwriter and the 
HttpServletResponse.

HERE IS THE SERVLET TEST CODE:

import java.io.IOException;
import java.io.PrintWriter;
import java.util.Enumeration;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public final class Server extends HttpServlet {
    
    /**
     * Respond to a GET request for the content produced by
     * this servlet.
     *
     * @param request The servlet request we are processing
     * @param response The servlet response we are producing
     *
     * @exception IOException if an input/output error occurs
     * @exception ServletException if a servlet error occurs
     */
    public void doGet(HttpServletRequest request,
                      HttpServletResponse response)
	throws IOException, ServletException {
	
	response.setContentType("text/xml");
	PrintWriter writer = response.getWriter();
	writer.println("buffersize:" + response.getBufferSize());
	
	
	writer.println("\nTest:");
	writer.println("initial isCommited:" + response.isCommitted());
	
	writer.println("\nresponse");
	writer.flush();
	writer.println("after writer.flush() isCommited:" +         
response.isCommitted());
	
	writer.println("\nParameters");	
	response.flushBuffer();
	writer.println("after response.flushBuffer() isCommited:" +         
response.isCommitted());
	
	Enumeration names = request.getParameterNames();
	while (names.hasMoreElements()) {
	    String name = (String) names.nextElement();
	    writer.println(name + ": " + request.getParameter(name));
	    writer.println("Waiting 2secs\n");
//THESE ARE THE 2 PROBLEMATIC LINES -NONE OF THEM WORKS WITH TOMCAT 4
	    writer.flush();
	    response.flushBuffer();
	    
	    try {
		Thread.sleep(2000);
	    }
	    catch (InterruptedException e){
	    }
	}
    }
    
    public void doPost(HttpServletRequest request, HttpServletResponse response)
	throws IOException, ServletException {
	doGet(request, response);
    }
}

AND HERE IS THE CLIENT CODE:

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.IOException;
import java.io.PrintWriter;
import java.net.URL;
import java.net.URLDecoder;
import java.net.URLEncoder;
import java.net.URLConnection;

public class Client {
    
    public static void main(String[] args) {
	String query = 
"http://localhost:8080/Server1/Server1?banana=yellow&snow=white&sea=blue";

	try {
	    URL url = new URL(query);
	    BufferedReader in = new BufferedReader(new 
InputStreamReader(url.openStream()));
	    String line;
	    while ((line = in.readLine()) != null)
		System.out.println(line);
	    
	} catch(IOException e) {
	    System.out.println("Error " + e);
	}
    }
}