-- 作者:admin
-- 发布时间:2010/9/2 22:47:25
-- [推荐]第二部分课堂讲稿——JSP
1、简单的使用 1、1 一个最为简单的JSP文件 不论手工来做,还是使用IDE只需建立下面文件并放入Web应用程序目录下即可,如: <html> <head> </head> <body> <% out.print("Hello!"); %> </body> </html>
http://localhost:8088/myweb/index.jsp 修改后无需重启Tomcat即可刷新看到新的结果
上述做法的真正代码是servlet代码,在编译执行JSP网页后,可以发现在<Tomcat>/work目录下存在新的java文件,里面就是一个servlet,名称为JSP文件名称加上“_jsp”后缀,它继承org.apache.jasper.runtime.HttpJspBase,而此类继承javax.servlet.http.HttpServlet。所以,里面有个_jspService方法,即包含JSP网页代码
1、2 JSP程序的部署配置 JSP程序也可以象servlet那样在web.xml中进行路径配置,如: <servlet> <servlet-name>exec</servlet-name> <jsp-file>/index.jsp</jsp-file> </servlet>
<servlet-mapping> <servlet-name>exec</servlet-name> <url-pattern>/exec</url-pattern> </servlet-mapping>
相应的jsp网页请求可以为:http://localhost:8088/myweb/exec
1、3 几个练习 时间显示之一: <html> <head> <title>Hello!</title> </head> <body> <%=new java.util.Date()%> </body> </html>
时间显示之二: <html> <head> <meta http-equiv = "refresh" c /> <title>A Simple JSP Example</title> <style type = "text/css"> .big { font-family: helvetica, arial, sans-serif; font-weight: bold; font-size: 2em; } </style> </head>
<body> <p class = "big">Simple JSP Example</p> <table style = "border: 6px outset;"> <tr> <td style = "background-color: black;"> <p class = "big" style = "color: cyan;"> <%= new java.util.Date() %> </p> </td> </tr> </table> </body> </html>
时间显示之三: <%@page import="java.util.GregorianCalendar"%> <%@page import="java.util.Date"%> <%@page c%>
<html> <head> </head>
<body> <h1> <% final int YEAR = 2050; GregorianCalendar target = new GregorianCalendar(); target.set(target.YEAR, YEAR); target.set(target.MONTH, 1); target.set(target.DATE, 1); target.set(target.AM_PM, 0); target.set(target.HOUR, 0); target.set(target.MINUTE, 0); target.set(target.SECOND, 0); Date Dtarget = (Date) target.getTime(); Date Dcurrent = new Date(); int i = Dtarget.compareTo(Dcurrent); if (i == 1) { long secs = Dtarget.getTime() - Dcurrent.getTime(); long days = (long) secs / (long) (1000 * 60 * 60 * 24); //毫秒与天的换算 out.print("距离" + YEAR + "年还有" + days + "天!"); } %> </h1> </body> </html>
显示不同字体之一: <%@page language="java"%>
<html> <head></head> <body> <% String str = "Welcome!"; int font_size = 0; for (int i = 0; i < str.length(); i++) { out.print("<font size="); out.print(++font_size); out.print(">"); out.print(str.substring(i, i + 1)); out.print("</font>"); } %> </body> </html>
显示不同字体之二: <%@page language="java"%>
<html> <head> </head>
<body> <% String str = "Welcome!"; int font_size = 0; for (int i = 0; i < str.length(); i++) { %> <font size=<%=++font_size%>> <%=str.charAt(i)%></font> <% } %> </body> </html>
1、4 输出星号三角形 <%@page language="java" c%>
<html> <head> </head>
<body style="font-family:宋体;font-size:28pt"> <% final int lineCount = 3; for (int c = 0; c < lineCount; c++) { for (int d = 0; d < lineCount - 1 - c; d++) out.print(" "); for (int d = 0; d < (c + 1) * 2 - 1; d++) out.print("*"); out.print("<br>"); } %> </body> </html>
[此贴子已经被作者于2010-12-12 18:13:20编辑过]
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