初学 Java Web 开发，请远离各种框架，从 Servlet 开发

<?xml version=‘1.0‘ encoding=‘utf-8‘?>
	<Server port="8005" shutdown="SHUTDOWN">
	  <Service name="Catalina">
	    <Connector port="8080" protocol="HTTP/1.1" connectionTimeout="20000" redirectPort="8443" URIEncoding="UTF-8"/>
	    <Engine name="Catalina" defaultHost="localhost">
	      <Host name="localhost">
	    <Context path="" docBase="D:\WORKDIR\ServletDemo\webapp" reloadable="true"/>
	      </Host>
	    </Engine>
	  </Service>
	</Server>

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE web-app PUBLIC "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN" 
	"http://java.sun.com/dtd/web-app_2_3.dtd">
<web-app>

	<servlet>
		<servlet-name>hello_world</servlet-name>
		<servlet-class>demo.HelloServlet</servlet-class>
		<load-on-startup>1</load-on-startup>
	</servlet>

	<servlet-mapping>
		<servlet-name>hello_world</servlet-name>
		<url-pattern>/hello</url-pattern>
	</servlet-mapping>

</web-app>

package demo;

import java.io.IOException;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;

public class HelloFilter implements Filter {

	@Override
	public void init(FilterConfig arg0) throws ServletException {
		System.out.println("Filter 初始化");
	}

	@Override
	public void doFilter(ServletRequest req, ServletResponse res,
			FilterChain chain) throws IOException, ServletException {
		HttpServletRequest request = (HttpServletRequest)req;
		System.out.println("拦截 URI="+request.getRequestURI());
		chain.doFilter(req, res);
	}

	@Override
	public void destroy() {
		System.out.println("Filter 结束");
	}
}

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE web-app PUBLIC "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN" 
						 "http://java.sun.com/dtd/web-app_2_3.dtd">
<web-app>

	<filter>
		<filter-name>helloFilter</filter-name>
		<filter-class>demo.HelloFilter</filter-class>
	</filter>

	<filter-mapping>
		<filter-name>helloFilter</filter-name>
		<url-pattern>/*</url-pattern>
	</filter-mapping>
	
	<servlet>
		<servlet-name>hello_world</servlet-name>
		<servlet-class>demo.HelloServlet</servlet-class>
		<load-on-startup>1</load-on-startup>
	</servlet>

	<servlet-mapping>
		<servlet-name>hello_world</servlet-name>
		<url-pattern>/hello</url-pattern>
	</servlet-mapping>

</web-app>

package org.apache.jsp;

import javax.servlet.*;
import javax.servlet.http.*;
import javax.servlet.jsp.*;
import java.util.*;

public final class test_jsp extends org.apache.jasper.runtime.HttpJspBase
    implements org.apache.jasper.runtime.JspSourceDependent {

  private static final JspFactory _jspxFactory = JspFactory.getDefaultFactory();

  private static java.util.List<String> _jspx_dependants;

  private javax.el.ExpressionFactory _el_expressionfactory;
  private org.apache.tomcat.InstanceManager _jsp_instancemanager;

  public java.util.List<String> getDependants() {
    return _jspx_dependants;
  }

  public void _jspInit() {
    _el_expressionfactory = _jspxFactory.getJspApplicationContext(getServletConfig().getServletContext()).getExpressionFactory();
    _jsp_instancemanager = org.apache.jasper.runtime.InstanceManagerFactory.getInstanceManager(getServletConfig());
  }

  public void _jspDestroy() {
  }

  public void _jspService(final HttpServletRequest request, final HttpServletResponse response)
        throws java.io.IOException, ServletException {

    final PageContext pageContext;
    HttpSession session = null;
    final ServletContext application;
    final ServletConfig config;
    JspWriter out = null;
    final Object page = this;
    JspWriter _jspx_out = null;
    PageContext _jspx_page_context = null;


    try {
      response.setContentType("text/html;charset=utf-8");
      pageContext = _jspxFactory.getPageContext(this, request, response,
      			null, true, 8192, true);
      _jspx_page_context = pageContext;
      application = pageContext.getServletContext();
      config = pageContext.getServletConfig();
      session = pageContext.getSession();
      out = pageContext.getOut();
      _jspx_out = out;

      out.write("\r\n");
      out.write("<html>\r\n");
      out.write("    <title>Test</title>\r\n");
      out.write("    <style>\r\n");
      out.write("    </style> \r\n");
      out.write("  <body>\r\n");
      out.write("<h1>Test Demo (oschina)</h1>\r\n");
      out.write("<table cellspacing=\"1\" cellpadding=\"5\">\r\n");

Enumeration Names=request.getHeaderNames();
while(Names.hasMoreElements())
{String name=(String)Names.nextElement();
String value=request.getHeader(name);
 
      out.write("\r\n");
      out.write(" <tr>\r\n");
      out.write(" <td>");
      out.print(name);
      out.write("</td>\r\n");
      out.write("  <td>");
      out.print(value);
      out.write("</td>\r\n");
      out.write(" \r\n");
      out.write(" </tr>\r\n");
      out.write(" ");

 }
  
      out.write("\r\n");
      out.write("</table>\r\n");
      out.write("  </body>\r\n");
      out.write("</html>");
    } catch (Throwable t) {
      if (!(t instanceof SkipPageException)){
        out = _jspx_out;
        if (out != null && out.getBufferSize() != 0)
          try { out.clearBuffer(); } catch (java.io.IOException e) {}
        if (_jspx_page_context != null) _jspx_page_context.handlePageException(t);
      }
    } finally {
      _jspxFactory.releasePageContext(_jspx_page_context);
    }
  }
}