package coreservlets; import java.io.*; import javax.servlet.*; import javax.servlet.http.*; import java.util.*; /** Illustrates the value of persistent HTTP connections for * pages that includes many images, applet classes, or * other auxiliary content that would otherwise require * a separate connection to retrieve. *

* Taken from Core Servlets and JSP, * http://www.apl.jhu.edu/~hall/csajsp/. * 1999 Marty Hall; may be freely used or adapted. */ public class FrameCell extends HttpServlet { public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { response.setContentType("text/html"); ByteArrayOutputStream byteStream = new ByteArrayOutputStream(512); PrintWriter out = new PrintWriter(byteStream, true); String persistenceFlag = request.getParameter("usePersistence"); boolean usePersistence = ((persistenceFlag == null) || (!persistenceFlag.equals("no"))); String title; if (usePersistence) { title = "Persistent"; } else { title = "Not Persistent"; } out.println(ServletUtilities.headWithTitle(title) + "\n" + "Cell " + request.getParameter("cellNum") + " (" + title + ")\n" + ""); if (usePersistence) { response.setContentLength(byteStream.size()); } byteStream.writeTo(response.getOutputStream()); } }