写一个经典的正则表达式
提取 <a> 标记   属性   href   中的值
------解决方案--------------------up
------解决方案--------------------用DOM行不? 
 getElementByTagName( "a ").getAttribute( "href ");
------解决方案--------------------		//提取href 
 		String a1= " <a target=\ "_blank\ " href=\ "http://www.cnta.com/\ " "; 
 		String  r= "href=\ "([^\ "]+) "; 
 		Pattern s=Pattern.compile(r); 
 		Matcher m1=s.matcher(a1); 
 		if(m1.find()) 
 			System.out.println( "href 为 "+m1.group(1));
------解决方案--------------------public static void main(String[] args) { 
     String a1 =  " <a href=\ "http://www.goodlrc.com/html/240.htm\ ">  "; 
     Pattern s = Pattern.compile( " <a\\s+href=\ "(.*?)\ ">  "); 
     Matcher m1 = s.matcher(a1); 
     if (m1.find()) 
         System.out.println( "href 为 " + m1.group(1)); 
 }