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package
org.apache.jsp;import
javax.servlet.*;import
javax.servlet.http.*;import
javax.servlet.jsp.*;import
java.util.*;public
final
class
index_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(HttpServletRequest request, HttpServletResponse response) throws
java.io.IOException, ServletException { PageContext pageContext = null; HttpSession session = null; ServletContext application = null; ServletConfig config = null; JspWriter out = null; Object page = this; JspWriter _jspx_out = null; PageContext _jspx_page_context = null; try
{ response.setContentType("text/html;charset=ISO-8859-1"); 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‘); out.write(‘\n‘);String path = request.getContextPath();String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/"; out.write("\r\n"); out.write("\r\n"); out.write("<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\">\r\n"); out.write("<html>\r\n"); out.write(" <head>\r\n"); out.write(" <base href=\""); out.print(basePath); out.write("\">\r\n"); out.write(" \r\n"); out.write(" <title>My JSP ‘index.jsp‘ starting page</title>\r\n"); out.write("\t<meta http-equiv=\"pragma\" content=\"no-cache\">\r\n"); out.write("\t<meta http-equiv=\"cache-control\" content=\"no-cache\">\r\n"); out.write("\t<meta http-equiv=\"expires\" content=\"0\"> \r\n"); out.write("\t<meta http-equiv=\"keywords\" content=\"keyword1,keyword2,keyword3\">\r\n"); out.write("\t<meta http-equiv=\"description\" content=\"This is my page\">\r\n"); out.write("\t<!--\r\n"); out.write("\t<link rel=\"stylesheet\" type=\"text/css\" href=\"styles.css\">\r\n"); out.write("\t-->\r\n"); out.write(" </head>\r\n"); out.write(" \r\n"); out.write(" <body>\r\n"); out.write(" \r\n"); out.write(" "); Date date = new
Date(); out.write(date.toLocaleString()); out.write("\r\n"); out.write(" </body>\r\n"); out.write("</html>\r\n"); } 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); } }} |
不管是JSP还是Servlet，虽然都可以用于开发动态web资源。但由于这2门技术各自的特点，在长期的软件实践中，人们逐渐把servlet作为web应用中的控制器组件来使用，而把JSP技术作为数据显示模板来使用。
其原因为，程序的数据通常要美化后再输出：
让jsp既用java代码产生动态数据，又做美化会导致页面难以维护。
让servlet既产生数据，又在里面嵌套html代码美化数据，同样也会导致程序可读性差，难以维护。
因此最好的办法就是根据这两门技术的特点，让它们各自负责各的，servlet只负责响应请求产生数据，并把数据通过转发技术带给jsp，数据的显示jsp来做。
原文：http://www.cnblogs.com/E-star/p/3516468.html