package com.adam;import java.util.HashMap;import java.util.Map;import java.util.regex.Matcher;import java.util.regex.Pattern;public class StringTemplateParser {	private String pstartTag = "${";	private String pendTag = "}";	/**	 * 	 * @param template 要解析的字符串	 * @param map 对应的值	 *   返回解析结果	 */	public String parse(String template,Map
    
      map){		StringBuffer temp = new StringBuffer(template);		Map
     
       tagMap = this.getTagIndex(template);			for(Map.Entry
      
        entry:tagMap.entrySet()){				//获得标识符				String tag = entry.getValue();				//获得替换的值，如果没有，则不变				String repVal = map.get(entry.getKey())==null?entry.getValue():map.get(entry.getKey());				//获得标识符在字符串中出现的次数				int index = 0;				//判断同一个标识符在字符串中出现的次数				while((index=template.indexOf(tag,index))!=-1){					//替换					//System.out.println(tag+"位置:"+index);					temp = temp.replace(temp.indexOf(tag), temp.indexOf(tag)+tag.length(), repVal);					index += tag.length(); 				}			}			return temp.toString();			}	/**	 * 获得key和对应的标识符如{age=${age}, name=${name}}	 * @param template	 *  	 */	protected Map
       
         getTagIndex(String template){		Map
        
          map = new HashMap
         
          (); Pattern pattern = Pattern.compile("\\$\\{[\\w]+\\}") ; Matcher matcher = pattern.matcher(template); int pstartLen = pstartTag.length(); while(matcher.find()){ //获得标示符 String tag = matcher.group(); //获得key String key = tag.substring(pstartLen, tag.lastIndexOf(pendTag)); map.put(key, tag); } return map; } public static void main(String[] args) { String template = "${age} hi,${name},${name} are you ${age}?"; Map
          
            map = new HashMap
           
            (); map.put("name", "adam"); map.put("age", "25"); StringTemplateParser stp = new StringTemplateParser(); System.out.println(stp.parse(template,map)); System.out.println(stp.getTagIndex(template)); }}