70 lines
2.8 KiB
HTML
70 lines
2.8 KiB
HTML
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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
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<html>
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<head>
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<META http-equiv="Content-Type" content="text/html; charset=utf-8">
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<LINK rel="stylesheet" type="text/css" href="../../../rzahg/ic.css">
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<title>Create the HTTP response</title>
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</head>
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<BODY>
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<!-- Java sync-link -->
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<SCRIPT LANGUAGE="Javascript" SRC="../../../rzahg/synch.js" TYPE="text/javascript"></SCRIPT>
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<h6><A NAME="servres"></A>Create the HTTP response</h6>
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<p>After the servlet request code, add the response code (in black text below):</p>
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<pre>import java.io.*;
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import java.util.*;
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import javax.servlet.*;
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import javax.servlet.http.*;
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public class ServletSample extends HttpServlet
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{
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public void doGet (HttpServletRequest request, HttpServletResponse response)
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throws ServletException, IOException
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{
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Enumeration keys;
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String key;
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String myName = "";
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keys = request.getParameterNames();
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while (keys.hasMoreElements())
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{
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key = (String) keys.nextElement();
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if (key.equalsIgnoreCase("myName")) myName = request.getParameter(key);
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}
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System.out.println("Name = ");
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if (myName == "") myName = "Hello";
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response.setContentType("text/html");
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response.setHeader("Pragma", "No-cache");
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response.setDateHeader("Expires", 0);
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response.setHeader("Cache-Control", "no-cache");
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PrintWriter out = response.getWriter();
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out.println("<html>");
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out.println("<head><title>Just a basic servlet</title></head>");
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out.println("<body>");
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out.println("<h1>Just a basic servlet</h1>");
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out.println ("<p>" + myName + ", this is a very basic servlet.");
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out.println("</body></html>");
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out.flush();
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}
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}
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</pre>
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<p>The HttpServletResponse object generates a response to return to the requesting client. Its methods allow you to set the response header and the response body.</p>
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<p>The first line of the Response header (response.setContentType("text/html");) identifies the MIME type of the response. The following three lines are often placed in servlet code to prevent Web browsers and proxy servers from caching dynamically-generated Web pages. If you want your dynamic Web page to be cached, remove these three lines of code.</p>
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<p>The response object also has the getWriter() method to return a PrintWriter object. The print() and println() methods of the PrintWriter object write the servlet response back to the client.</p>
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</body>
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</html>
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