getheader.java

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/************************* GetHeader.java ****************/
import java.io.*;
import java.util.*;
import javax.servlet.*;
import javax.servlet.http.*;
public class GetHeader extends HttpServlet
  {
  public void doGet(HttpServletRequest req,
                    HttpServletResponse res)
  throws ServletException, IOException
    {
    res.setContentType("text/plain");
    PrintWriter out = res.getWriter();
    out.println("Request Headers:");
    out.println();
    Enumeration e = req.getHeaderNames();
    while (e.hasMoreElements())
      {
      String name = (String) e.nextElement();
      String value = req.getHeader(name);
      if (value != null)
        out.println(name + ": " + value);
      }
    }
  }