JSP基础语法-关于JSP中的注释

不念不忘少年蓝@ 2024-04-17 18:18 96阅读 0赞

[JSP基础语法][JSP]

3.3、关于JSP中的注释  
      JSP中的注释一定要编写到JSP的专业注释符号当中，只有这里的注释信息不会被翻译到java源代码当中，效率较高。其它的任何一种注释都会被翻译到java源代码当中，这样效率很低。  
            3.3.1、JSP的注释语法格式：  
                <%--  
                    注释内容  
                --%>  
 ————————————————  
JSP文件：

<script type="text/javascript">
    	/*
    		This is JavaScript Comment!
    	*/
    	/*
    	function sayHello(){
    	
    	}
    	*/
    </script>
    
    <style type="text/css">
    	/*
    		This is CSS Comment!
    	*/
    </style>
    
    <%--
    	This is JSP Comment!
    	This is JSP Comment!
    	This is JSP Comment!
    	This is JSP Comment!
    	This is JSP Comment!
    	This is JSP Comment!
    --%>
    
    <%
    	//This is Java Comment!
    	//System.out.println("hello world!");
    %>

Tomcat服务器翻译JSP为work目录下项目对应Java文件的service方法：

public void _jspService(final javax.servlet.http.HttpServletRequest request, final javax.servlet.http.HttpServletResponse response)
            throws java.io.IOException, javax.servlet.ServletException {
    
        final javax.servlet.jsp.PageContext pageContext;
        javax.servlet.http.HttpSession session = null;
        final javax.servlet.ServletContext application;
        final javax.servlet.ServletConfig config;
        javax.servlet.jsp.JspWriter out = null;
        final java.lang.Object page = this;
        javax.servlet.jsp.JspWriter _jspx_out = null;
        javax.servlet.jsp.PageContext _jspx_page_context = null;
    
    
        try {
          response.setContentType("text/html");
          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("\r\n");
          out.write("<script type=\"text/javascript\">\r\n");
          out.write("\t/*\r\n");
          out.write("\t\tThis is JavaScript Comment!\r\n");
          out.write("\t*/\r\n");
          out.write("\t/*\r\n");
          out.write("\tfunction sayHello(){\r\n");
          out.write("\t\r\n");
          out.write("\t}\r\n");
          out.write("\t*/\r\n");
          out.write("</script>\r\n");
          out.write("\r\n");
          out.write("<style type=\"text/css\">\r\n");
          out.write("\t/*\r\n");
          out.write("\t\tThis is CSS Comment!\r\n");
          out.write("\t*/\r\n");
          out.write("</style>\r\n");
          out.write("\r\n");
          out.write("\r\n");
          out.write("\r\n");
    
    	//This is Java Comment!
    	//System.out.println("hello world!");
    
          out.write("\r\n");
          out.write("\r\n");
        } catch (java.lang.Throwable t) {
          if (!(t instanceof javax.servlet.jsp.SkipPageException)){
            out = _jspx_out;
            if (out != null && out.getBufferSize() != 0)
              try {
                if (response.isCommitted()) {
                  out.flush();
                } else {
                  out.clearBuffer();
                }
              } catch (java.io.IOException e) {}
            if (_jspx_page_context != null) _jspx_page_context.handlePageException(t);
            else throw new ServletException(t);
          }
        } finally {
          _jspxFactory.releasePageContext(_jspx_page_context);
        }
      }

返回前台源文件：

[JSP]: https://blog.csdn.net/cheng_feng_xiao_zhan/article/details/100144010