日期:2014-05-20  浏览次数:20826 次

求处理含有占位符(Placeholder)的字符串的工具类库!
本人想未来把自己的产品进行国际化,所以把程序给外部系统做出的所有提示信息都存放到文件messages.properties。
Example:
messages.properties
Java code

web.services.members.response.msg.notfound=\u5bf9\u4e0d\u8d77\uff0c\u6ca1\u6709\u53d1\u73b0\u4e0e[${username}]\u76f8\u5339\u914d\u7528\u6237\uff01
web.services.members.response.msg.found=\u5171\u627e\u5230\u4e0e[${username}]\u76f8\u5339\u914d\u7684\u7528\u6237${count}\u4e2a\uff01
web.services.members.response.msg.exception=\u670d\u52a1\u5668\u51fa\u73b0\u5f02\u5e38\uff0c\u8bf7\u7a0d\u540e\u518d\u8bd5\uff01
web.services.members.response.msg.error=\u670d\u52a1\u5668\u51fa\u73b0\u5185\u90e8\u9519\u8bef\uff01


messages.properties实际内容如下:
web.services.members.response.msg.notfound=没有发现与[${username}]相匹配用户!
web.services.members.response.msg.found=共找到与[${username}]相匹配的用户${count}个!
web.services.members.response.msg.exception=服务器出现异常,请稍后再试!
web.services.members.response.msg.error=服务器出现内部错误!

稍后,我新创建一个类MessageBundle:
Java code

package com.dongantech.eshop.web.util;

import java.util.*;
import java.io.*;

public class MessageBundle {
    public static Properties PROPS = null ;
    
    private Map bundle =  null;
    
    static {
        InputStream propertiesInputStream = MessageBundle.class.getResourceAsStream("/messages.properties");
        PROPS = new Properties();
        try {
            PROPS.load(propertiesInputStream);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    public MessageBundle(){
        bundle = new HashMap();
    }
    public void setBundle(Map theBundle){
        bundle = theBundle;
    }
    public Map getBundle(){
        return bundle ;
    }
    public String getMessage(String theMsgKey){
        return (String)bundle.get(theMsgKey);
    }
    public void putIntoBundle(String theMsgKey){
        String msgFrame = MessageBundle.PROPS.getProperty(theMsgKey);
        bundle.put(theMsgKey,msgFrame);
    }
}


这样,我的Servlet就自己去打包所需要的信息成一个MessageBundle对象,由于信息反馈对于系统来说是很频繁的活动,如果每一个这样的对象(Servlet)都包含一个MessageBundle对象,就会避免了多个Servlet间对某信息集合对象(使用单例模式方式)请求占用所带来的执行延时。
Java code

public class MemberManagerServlet extends HttpServlet{
    public static final String MSG_KEY_NOT_FOUND = "web.services.members.response.msg.notfound" ; 
    public static final String MSG_KEY_FOUND = "web.services.members.response.msg.found" ;
    public static final String MSG_KEY_EXCEPTION = "web.services.members.response.msg.exception" ;
    public static final String MSG_KEY_ERROR = "web.services.members.response.msg.error" ;
    
    private Map requestHandlers = null ;
    private PageLocator pageLocator = null ;
    private MessageBundle messageBundle = null ;
    
    public MemberManagerServlet(){
        requestHandlers = new HashMap();
        pageLocator = new PageLocator();
        
        pageLocator.registerPage(SimpleResponse.TYPE_FOUND,MemberManagerServlet.PAGE_FOUND );
        pageLocator.registerPage(SimpleResponse.TYPE_NOT_FOUND,MemberManagerServlet.PAGE_NOT_FOUND);
        pageLocator.registerPage(SimpleResponse.TYPE_EXCEPTION,MemberManagerServlet.PAGE_EXCEPTION);
        pageLocator.registerPage(SimpleResponse.TYPE_ERROR,MemberManagerServlet.PAGE_ERROR);
        
        messageBundle.putIntoBundle(MemberManagerServlet.MSG_KEY_NOT_FOUND);
        messageBundle.putIntoBundle(MemberManagerServlet.MSG_KEY_FOUND);
        messageBundle.putIntoBundle(MemberManagerServlet.MSG_KEY_EXCEPTION);
        messageBundle.putIntoBundle(MemberManagerServlet.MSG_KEY_ERROR);
    }
    public void init(ServletConfig config){
        try {
            super.init(config);
        } catch (ServletException e) {
            e.printStackTrace();
        }
    }
    public void doGet(HttpServletRequest httpReq,HttpServletResponse httpResp){
        Response response = processRequest(httpReq,httpResp);
        try {
            deliver(response);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
    
    public void doPost(HttpServletRequest httpReq,HttpServletResponse httpResp){
        Response response = processRequest(httpReq,httpResp);
        try {
            deliver(response);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
    
    public Response processRequest(HttpServletRequest httpReq,HttpServletResponse httpResp){
        Response response = null ;
        String handlerName = httpReq.getParameter("request");
        RequestHandler handler = getHandler(handlerName);
        Request request = buildRequest(httpReq);
        try {
            response = handler.process(request);
            response.getContext().put("page",getPage(response.getType()));
        } catch (Exception e) {
            response = new SimpleResponse(SimpleResponse.TYPE_ERROR);
            e.printStackTrace();
        }
        return response ;
    }

}