import java.text.NumberFormat;
public class NumFormat {
public static void main(String[] args) {
double a=1;
double b=3;
System.out.println(percent(a, b));
}
public static String percent(double num1,double num2){//创建获取两个数的百分比芳芳
String str = "";//创建字符串对象
double num3 = num1 / num2;//获取两个参数的商
NumberFormat numFormat = NumberFormat.getPercentInstance();//返回当前默认语言环境的百分比格式
numFormat.setMinimumFractionDigits(2);//设置百分数的小数部分所允许的最小位数，如果将参数设置为负数，则使用0
str = numFormat.format(num3);//格式规范
return str;
}
}
|
烂机器一般主要用在网页设计中，主要过滤后台，防止没有登录的用户对数据进行乱改乱添加，不过对前台的页面一般还是可以访问的，因为前台主要是一些超链接，和一些action请求。如：
<!-- 登录过滤器 -->
<filter>
<filter-name>onlineFilter</filter-name>
<filter-class>
com.seosum.infosub.util.OnlineFilter
</filter-class>
</filter>
<filter-mapping>
<filter-name>onlineFilter</filter-name>
<url-pattern>/pages/back/*</url-pattern>
</filter-mapping>
--------------------------------------------------------------------------------------------
import java.io.IOException;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
public class OnlineFilter extends HttpServlet implements Filter{
/**
*
*/
private static final long serialVersionUID = 1L;
@Override
public void doFilter(ServletRequest request, ServletResponse response,
FilterChain chain) throws IOException, ServletException {
// 这里设置如果没有登录将要转发到的页面
RequestDispatcher dispatcher = request.getRequestDispatcher("/index.jsp");
HttpServletRequest req = (HttpServletRequest) request;
HttpServletResponse res = (HttpServletResponse) response;
HttpSession session = req.getSession(true);
String username = (String)session.getAttribute("username");
if(username == null || "".equals(username.trim())){
// 跳转到登录页面
dispatcher.forward(request, response);
res.setHeader("Cache-Control", "no-store");
res.setDateHeader("Expires", 0);
res.setHeader("Pragma", "no-cache");
}else{
chain.doFilter(request, response);
}
}
@Override
public void init(FilterConfig filterConfig) throws ServletException {
// TODO Auto-generated method stub
}
}
<!-- 登录过滤器 -->
<filter>
<filter-name>onlineFilter</filter-name>
<filter-class>
com.huawei.filter.util.OnlineFilter
</filter-class>
</filter>
<filter-mapping>
<filter-name>onlineFilter</filter-name>
<url-pattern>/pages/*</url-pattern>//过滤掉拥有在pages下的页面，不过滤action
</filter-mapping>
<struts>
<package name="login" extends="struts-default">
<action name="add" class="com.huawei.filter.action.LoginAction" method="addLogin">
<result name="success" type="redirect">list.action</result>
<result name="fail">/pages/error.jsp</result>
</action>
<action name="list" class="com.huawei.filter.action.LoginAction" method="listLogin">
<result name="success">/pages/listlogin.jsp</result>
</action>
</package>
</struts>
|
public static void main(String[] args) {
System.setProperty("a", "nihao");//设置一个属性
String pro= System.getProperty("a");
System.out.println(pro);//获取自己设置的一个属性
System.out.println(System.getProperty("file.separator"));//获取当前系统中文件的分隔符
System.setProperty("homePage","http://" + Utils.getServerIp()+":" + PropertysConstants.TOMCAT_PORT + PropertysConstants.ACCESS_PATH);
}
<%@ page language="java" contentType="text/html; charset=GBK" isErrorPage="true" pageEncoding="GBK"%>
<html>
<body>
<font size="1">找不到网页 </font>
<br>
<font size="1">您要查看的网页可能已被删除、名称已被更改，或者暂时不可用。</font>
<br>
--------------------------------------------------------------------------------
<br>
<font size="1">请尝试以下操作:</font>
<br>
<font size="1">如果您已经在地址栏中输入该网页的地址，请确认其拼写正确。</font>
<br>
<ul>
<li><font size="1">打开<a href= "<%=System.getProperty("homePage")%>" target="_top"><%=System.getProperty("homePage")%></a>主页，然后查找指向您感兴趣信息的链接。</font></li>
<li><font size="1">单击后退按钮，尝试其他链接。</font></li>
<li><font size="1">单击搜索，寻找 Internet 上的信息。</font></li>
</ul>
<font size="1">HTTP 404 - 未找到文件</font>
<br>
<font size="1">Internet Explorer</font>
</body>
</html>
|
private String getWorkPath(){
URL root = this.getClass().getResource("/");
String path =null;
try {
path = URLDecoder.decode(root.getPath(), "UTF-8");
} catch (UnsupportedEncodingException e) {
// TODO Auto-generated catch block
e.printStackTrace();
return null;
}
if(path.startsWith("jar:")){
path = path.substring(4, path.length());
}
StringBuffer sb = new StringBuffer();
String[] temp = path.split("/");
for( int i=1; i<temp.length; i++ ) {
if( temp[i].indexOf("!") == -1 ) {
sb.append( temp[i] + "/" );
}
else {
break;
}
}
path = sb.toString();
return path;
}
|
