64 lines
2.1 KiB
HTML
64 lines
2.1 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>Get the HTTP request information</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="servreq"></A>Get the HTTP request information</h6>
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<p>After the method declaration, add the request 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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}
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}
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</pre>
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<p>This new section of code handles the client request parameters. The HttpServletRequest class has the following specific methods to retrieve information provided by the client:</p>
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<ul>
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<li><p><strong>getParameterNames()</strong><br>
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This method returns the names of the parameters in an enumeration of strings.</p></li>
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<li><p><strong>getParameterValues()</strong><br>
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This method returns the values of the parameters in an array of strings.</p></li>
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<li><p><strong>getParameter()</strong><br>
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This method returns a single parameter value as a string. Use this method when you know the client request returns only one parameter.</p></li>
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</ul>
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<p>In the case of ServletSample, the getParameterNames() method gets the name of the parameters, and the getParameter() method gets the value of the myName parameter.</p>
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</body>
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</html>
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