JSP Tutorials - Herong's Tutorial Examples - v5.11, by Herong Yang
Execution Result of CurrentTime.jspx
This section describes execution result of the CurrentTime.jspx tutorial example. Converted Servlet class shows that action 'include' element is processed differently than directive 'include' elements by the Tomcat server.
After deploy those JSP Documents presented in the previous tutorial, I tried to visit the main JSP Document with a browser at: http://localhost:8080/CurrentTime.jspx. I got the following output:
Current time in different time zones: America/New_York: 7:35 PM America/Los_Angeles: 4:35 PM Asia/Shanghai: 7:35 AM Europe/Paris: 12:35 AM Europe/Moscow: 3:35 AM Current JVM: java.vm.name: Java HotSpot(TM) 64-Bit Server VM java.vm.version: 10.0.1+10 os.name: Windows 7 os.version: 6.1 Current Time: 19:35:06 EDT 2018
If I visit the first include JSP Document with a browser at: http://localhost:8080/JvmStamp.jspx. I will get an invalid HTML page, but the page source is still a good XML document:
<b>Current JVM:</b><br/>java.vm.name: Java HotSpot(TM) 64-Bit Server VM<br/> java.vm.version: 10.0.1+10<br/> os.name: Windows 7<br/> os.version: 6.1<br/>
If I visit the second include JSP Document with a browser at: http://localhost:8080/TimeStamp.jspx. I will get an invalid HTML page, but the page source is still a good XML document:
<b>Current Time: </b>19:36:05 EDT 2018
Now you want to see the Servlet class code converted from the main JSP Document, CurrentTime.jspx, here it is:
/* * Generated by the Jasper component of Apache Tomcat * Version: Apache Tomcat/9.0.12 * ... */ package org.apache.jsp; import javax.servlet.*; import javax.servlet.http.*; import javax.servlet.jsp.*; import java.util.*; import java.text.*; public final class CurrentTime_jspx extends org.apache.jasper.runtime.HttpJspBase implements org.apache.jasper.runtime.JspSourceDependent { private Date now; private JspWriter out; private void printTime(String tz) throws Throwable { DateFormat df = DateFormat.getInstance(); df.setTimeZone(TimeZone.getTimeZone(tz)); out.println(tz+": "+df.format(now)+"<br/>"); } private static final javax.servlet.jsp.JspFactory _jspxFactory = javax.servlet.jsp.JspFactory.getDefaultFactory(); private static java.util.Map<java.lang.String,java.lang.Long> _jspx_dependants; static { _jspx_dependants = new java.util.HashMap<java.lang.String,java.lang.Long>(1); _jspx_dependants.put("/JvmStamp.jspx", Long.valueOf(1351726198882L)); } private javax.el.ExpressionFactory _el_expressionfactory; private org.apache.tomcat.InstanceManager _jsp_instancemanager; public java.util.Map<java.lang.String,java.lang.Long> 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 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;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("<html>"); out.write("<body>"); out.write("<p>"); out.write("<b>"); out.write("Current time in different time zones:"); out.write("</b>"); out.write("<br/>"); this.out = out; now = new Date(); printTime("America/New_York"); printTime("America/Los_Angeles"); printTime("Asia/Shanghai"); printTime("Europe/Paris"); printTime("Europe/Moscow"); out.write("</p>"); out.write("<p>"); out.write("<b>"); out.write("Current JVM:"); out.write("</b>"); out.write("<br/>"); String s; s = "java.vm.name"; out.println(s+": "+System.getProperty(s)+"<br/>"); s = "java.vm.version"; out.println(s+": "+System.getProperty(s)+"<br/>"); s = "os.name"; out.println(s+": "+System.getProperty(s)+"<br/>"); s = "os.version"; out.println(s+": "+System.getProperty(s)+"<br/>"); out.write("</p>"); out.write("<p>"); org.apache.jasper.runtime.JspRuntimeLibrary.include( request, response, "TimeStamp.jspx", out, false); out.write("</p>"); out.write("</body>"); out.write("</html>"); } catch (java.lang.Throwable t) { if (!(t instanceof javax.servlet.jsp.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); else throw new ServletException(t); } } finally { _jspxFactory.releasePageContext(_jspx_page_context); } } }
Notice that:
Table of Contents
JSP (JavaServer Pages) Overview
Tomcat Installation on Windows Systems
►Syntax of JSP Pages and JSP Documents
Syntactic Elements of a JSP Page
JSP Document - JSP Page in XML Format
JSP Document - JSP Version Error
Writing Scriptlet Element in XML Format
Writing Directive Element in XML Format
Writing Action Element in XML Format
"include" Directive and Action Elements
►Execution Result of CurrentTime.jspx
JavaBean Objects and "useBean" Action Elements
Managing HTTP Response Header Lines
Non-ASCII Characters Support in JSP Pages
Overview of JSTL (JSP Standard Tag Libraries)
Multiple Tags Working Together
Using Tomcat on CentOS Systems
Connecting to SQL Server from Servlet