JDBC+Servlet+JSP整合开发之22.JSP简介
�C对JSP的需求
�CJSP的结构
�CJSP的好处
�CJSP实例
?创建一个简单的JSP页面
�CJSP的结构
�CJSP的好处
�CJSP实例
?创建一个简单的JSP页面
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? JSP
�CJSP 全称Java Server Page
?对JSP的需求
�C使用servlet可以容易地完成下述任务：
? 读取表单数据
? 读取HTTP请求报头
? 设置HTTP状态代码和响应报头
? 使用cookie以及进行会话跟踪
?跨servlet共享数据
? 跨请求记录数据
? 获得有趣且报酬丰厚的工作
? 但使用servlet也有不尽如人意的地方：
�C使用println语句生成HTML
�C维护上述的HTML
�CJSP 全称Java Server Page
?对JSP的需求
�C使用servlet可以容易地完成下述任务：
? 读取表单数据
? 读取HTTP请求报头
? 设置HTTP状态代码和响应报头
? 使用cookie以及进行会话跟踪
?跨servlet共享数据
? 跨请求记录数据
? 获得有趣且报酬丰厚的工作
? 但使用servlet也有不尽如人意的地方：
�C使用println语句生成HTML
�C维护上述的HTML
? JSP的结构
�C思想:
?大部分的页面使用常规的HTML
?用特殊的标签将servlet代码标记出来
?整个JSP页面最终转换成servlet（仅执行一次），实际
被调用的是servlet（每个请求）
�C示例
�C思想:
?大部分的页面使用常规的HTML
?用特殊的标签将servlet代码标记出来
?整个JSP页面最终转换成servlet（仅执行一次），实际
被调用的是servlet（每个请求）
�C示例
使用Servlet输出0~9的页面
LoopServlet
测试
使用JSP输出0~9的页面
MyFirstJsp.jsp
测试
看一下JSP页面转换的Servlet文件存放在哪里哈~
MyFirstJsp_jsp.java
package org.apache.jsp;
import javax.servlet.*;
import javax.servlet.http.*;
import javax.servlet.jsp.*;
import java.util.*;
public final class MyFirstJsp_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 _jspx_dependants;
private javax.el.ExpressionFactory _el_expressionfactory;
private org.apache.AnnotationProcessor _jsp_annotationprocessor;
public Object getDependants() {
return _jspx_dependants;
}
public void _jspInit() {
_el_expressionfactory = _jspxFactory.getJspApplicationContext(getServletConfig().getServletContext()).getExpressionFactory();
_jsp_annotationprocessor = (org.apache.AnnotationProcessor) getServletConfig().getServletContext().getAttribute(org.apache.AnnotationProcessor. class.getName());
}
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 'MyFirstJsp.jsp' starting page</title>\r\n");
out.write(" \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("\r\n");
out.write(" </head>\r\n");
out.write(" \r\n");
out.write(" <body>\r\n");
out.write(" \t<h1>My First JSP!</h1>\r\n");
out.write(" ");
for(int i=0;i<10;i++){
out.println(i);
out.print("<br/>");
}
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);
}
}
}
import javax.servlet.*;
import javax.servlet.http.*;
import javax.servlet.jsp.*;
import java.util.*;
public final class MyFirstJsp_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 _jspx_dependants;
private javax.el.ExpressionFactory _el_expressionfactory;
private org.apache.AnnotationProcessor _jsp_annotationprocessor;
public Object getDependants() {
return _jspx_dependants;
}
public void _jspInit() {
_el_expressionfactory = _jspxFactory.getJspApplicationContext(getServletConfig().getServletContext()).getExpressionFactory();
_jsp_annotationprocessor = (org.apache.AnnotationProcessor) getServletConfig().getServletContext().getAttribute(org.apache.AnnotationProcessor. class.getName());
}
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 'MyFirstJsp.jsp' starting page</title>\r\n");
out.write(" \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("\r\n");
out.write(" </head>\r\n");
out.write(" \r\n");
out.write(" <body>\r\n");
out.write(" \t<h1>My First JSP!</h1>\r\n");
out.write(" ");
for(int i=0;i<10;i++){
out.println(i);
out.print("<br/>");
}
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);
}
}
}
? JSP的好处
�C尽管JSP技术能够做的事情并不比servlet多，但JSP可以使下述任务更为容易：
? 输出HTML
? 阅读和维护这些HTML
�CJSP使得下面的做法成为可能：
? 使用标准的HTML工具，比如Macromedia DreamWeaver或FrontPage
? 由小组的另外一些成员完成HTML布局，不关注Java编程
�CJSP鼓励我们：
? 将创建内容（Java）代码同表示内容的（HTML）代码分离开来
�C尽管JSP技术能够做的事情并不比servlet多，但JSP可以使下述任务更为容易：
? 输出HTML
? 阅读和维护这些HTML
�CJSP使得下面的做法成为可能：
? 使用标准的HTML工具，比如Macromedia DreamWeaver或FrontPage
? 由小组的另外一些成员完成HTML布局，不关注Java编程
�CJSP鼓励我们：
? 将创建内容（Java）代码同表示内容的（HTML）代码分离开来
? JSP实例
�C创建一个简单的JSP页面
�C创建一个简单的JSP页面
