站点的网站计数器的操作
<%@ page import="java.math.BigInteger" %>
<%@ page import="java.io.File" %>
<%@ page import="java.util.Scanner" %>
<%@ page import="java.io.FileInputStream" %>
<%@ page import="java.io.PrintStream" %>
<%@ page import="java.io.FileOutputStream" %>
<%@ page import="java.util.zip.InflaterOutputStream" %><%--
Created by IntelliJ IDEA.
User: ming
Date: 19-3-12
Time: 下午10:25
To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>Title</title>
</head>
<body>
<%
// 定义全局变量
BigInteger count = null;
%>
<%!
// 获取计数器
public BigInteger load(File file){
BigInteger count = null;
try{
// 若文件存在则读取
if(file.exists()){
Scanner scanner = null;
// 获取到文件的输入流
scanner = new Scanner(new FileInputStream(file));
// 对计数器内容进行加1
if(scanner.hasNext()){
count = new BigInteger(scanner.next());
}
scanner.close();
}else{
count = new BigInteger("0");
save(file, count);
}
}catch (Exception e){
e.printStackTrace();
}
return count;
}
// 计数文件保存回文件
public void save(File file, BigInteger count){
try{
PrintStream printStream = null;
printStream = new PrintStream(new FileOutputStream(file));
// 流中输入对象
printStream.println(count);
printStream.close();
}catch (Exception e){
e.printStackTrace();
}
}
%>
<%
// 获取文件路径
String fileName = this.getServletContext().getRealPath("/") + "count.txt";
// 定义file对象
File file = new File(fileName);
// 进行加
if(session.isNew()) {
synchronized (this) {
count = load(file);
System.out.println(count);
count = count.add(new BigInteger("1"));
save(file, count);
}
}
%>
您是第<%=count%>
</body>
</html>
web映射
文件保存在WEB-INF文件夹下,永远无法访问,此时,需要修改/WEB-INF/web.xml文件即可,达到映射的目的
修改xml文件如下
<!DOCTYPE web-app PUBLIC
"-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
"http://java.sun.com/dtd/web-app_2_3.dtd" >
<web-app>
<display-name>Archetype Created Web Application</display-name>
<servlet>
<servlet-name>he</servlet-name>
<jsp-file>/WEB-INF/he.jsp</jsp-file>
</servlet>
<servlet-mapping>
<servlet-name>he</servlet-name>
<url-pattern>/hello</url-pattern>
</servlet-mapping>
</web-app>
直接更新,但不重启,发现不能加载.
此时.即Tomcat需要重写配置属性
此时访问
http://localhost:8080/hello
即可访问
config
config用于获得
