中英文切换(servlet)

doit

创建过滤

packagecom.i18n.filter;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.annotation.WebInitParam;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.FileInputStream;
import java.io.IOException;
import java.util.Properties;

@WebFilter(filterName = "Filter", urlPatterns = "/*",initParams ={@WebInitParam(name = "default",value = "en")})
public class MyFilter implements Filter {
public void destroy() {
}

public void doFilter(ServletRequest req, ServletResponseresp, FilterChain chain) throwsServletException,IOException {
        HttpServletRequest request =(HttpServletRequest) req;
        HttpServletResponse response =(HttpServletResponse) resp;
        request.setCharacterEncoding("UTF-8");
        response.setCharacterEncoding("UTF-8");
        String .getParameter("language");
        if (lang != null) {
            try{
                String sFile =request.getServletContext().getRealPath("/") + "/WEB-INF/messages_" + lang + ".properties";
                Properties properties = new Properties();
                properties.load(new FileInputStream(sFile));
                request.getSession().setAttribute("i18n", properties);
            } catch (Exception e) {
                System.out.println(e.getMessage());
            }
        }

chain.doFilter(req, resp);
}

public void init(FilterConfig config) throws ServletException {
        try {
            String .getInitParameter("default");
            if (lang == null) lang = "en";
            String sFile =config.getServletContext().getRealPath("/") + "/WEB-INF/messages_" + lang + ".properties";
            Properties properties = new Properties();
            properties.load(new FileInputStream(sFile));
           config.getServletContext().setAttribute("i18n", properties);
        } catch (Exception e) {
            System.out.println(e.getMessage());
        }
    }

}

创建properties文件

messages_en.properties

china=chinese
tag=tag
el=el

messages_zh.properties

china=中国
tag=标签
el=EL表达式

创建标签

package com.i18n.tag;

import javax.servlet.jsp.JspException;
import javax.servlet.jsp.JspWriter;
import javax.servlet.jsp.PageContext;
import javax.servlet.jsp.tagext.SimpleTagSupport;
import java.io.IOException;
import java.util.Properties;

public class I18nTag extends SimpleTagSupport {
private String sKey;

public String getsKey() {
return sKey;
}

public void setsKey(String sKey) {
this. sKey = sKey;
}

@Override
     public void doTag()  throws JspException, IOException {
        PageContext pageContext = (PageContext) getJspContext();
        Properties prop = (Properties) pageContext.getSession().getAttribute( "i18n");
         if (prop ==  null) prop = (Properties) pageContext.getServletContext().getAttribute( "i18n");
        JspWriter out = pageContext.getOut();
         if (prop ==  null)
            out.print( sKey);
         else
            out.print(prop.getProperty( sKey));
    }
}

配置TLD

<? xml version= "1.0" encoding= "ISO-8859-1"?>

< taglib xmlns= "http://java.sun.com/xml/ns/javaee"
         xmlns: xsi = "http://www.w3.org/2001/XMLSchema-instance"
         xsi :schemaLocation= "http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-jsptaglibrary_2_1.xsd"
         version= "2.1">

< tlib-version>1.0</ tlib-version>
< short-name>zsz</ short-name>
< uri>http://www.zsz.org</ uri>

< tag>
       < name>i18n</ name>
       < tag-class>com.i18n.tag.I18nTag</ tag-class>
       < body-content>empty</ body-content>
       < attribute>
           < name>sKey</ name>
           < required>true</ required>
       </ attribute>
   </ tag>

</ taglib>

使用i18n

<%@  page contentType=" text/html;charset=UTF-8"  language=" java" %>
<%@  taglib prefix=" zsz"  uri=" http://www.zsz.org" %>
< html>
  < head>
    < meta charset= "UTF-8">
    < title>$Title$</ title>
  </ head>
  < body>
  < a href= "?language=zh">中</ a>< a  href= "?language=en">en</ a>< hr>
< zsz :i18n sKey= "tag"></ zsz :i18n>    < zsz :i18n  sKey= "china"/>
  < hr>
  ${i18n.el }  :   ${i18n.china }
  </ body>
</ html>