请大神帮我写个正则表达式

我有段格式的字符串，我要取出里面的img标签里src的值 并替换新的地址

<p>12345678</p><p>3<img src="http://192.168.20.12/PIM/wave/BC17062302747013/AWBB7339959/07-Printscreen/tmall/DETAIL/CP-3.jpg">
<img src="http://192.168.20.12/PIM/wave/BC1702747013/AWBB7339959/07-Printscreen/tmall/DETAIL/XJT-1.jpg"></p>

推荐此博客：http://blog.csdn.net/huweijun_2012/article/details/51900814?locationNum=2&fps=1
楼主可以参考下

public class Regex {
public static void main(String[] args) {
//测试用文本 str
String str="";
String regex=" System.out.println(getRegexResult(str,regex).toString());
}
public static List getRegexResult(String sb,String regex){
List resultlist=new ArrayList();
Pattern p=Pattern.compile(regex);
Matcher m=p.matcher(sb.toString());
while(m.find()){
resultlist.add(m.group(1));
}
return resultlist;
}
}
//===============
//运行结果 存放在List里面 [http://192.168.20.121//sssssss1.jpg]

String str="<p>12345678</p><p>3<img src=\"http://192.168.20.12/PIM/wave/BC17062302747013/AWBB7339959/07-Printscreen/tmall/DETAIL/CP-3.jpg\">"+
"<img src=\"http://192.168.20.12/PIM/wave/BC1702747013/AWBB7339959/07-Printscreen/tmall/DETAIL/XJT-1.jpg\"></p>";
    Pattern p=Pattern.compile("src=\"([^\"]+)\"");
    Matcher m=p.matcher(str);
    while(m.find()){
        System.out.println(m.group(1));
    }
    结果在下面
    http://192.168.20.12/PIM/wave/BC17062302747013/AWBB7339959/07-Printscreen/tmall/DETAIL/CP-3.jpg
http://192.168.20.12/PIM/wave/BC1702747013/AWBB7339959/07-Printscreen/tmall/DETAIL/XJT-1.jpg

public class Regex {
public static void main(String[] args) {
//
String str="";
String regex=" System.out.println(getRegexResult(str,regex));
}
public static List getRegexResult(String sb,String regex){
//String regex=" List resultlist=new ArrayList();
Pattern p=Pattern.compile(regex);
Matcher m=p.matcher(sb.toString());
while(m.find()){
resultlist.add(m.group(1));
}
return resultlist;
}
}

 String str="<img src=\"http://192.168.20.12/PIM/wave1.jpg\">";
        String regex="<img src=\"([\\w\\s.:/]+?)\"";
        System.out.println(getRegexResult(str,regex));

//直接贴代码被屏蔽了，在你宝地再发下

 public class Regex {
    public static void main(String[] args) {
        //<img src="http://192.168.20.12/PIM/wave1.jpg">
        String str="<img src=\"http://192.168.20.12/PIM/wave1.jpg\">";
        String regex="<img src=\"([\\w\\s.:/]+?)\"";
        System.out.println(getRegexResult(str,regex));
    }
    public static List<String> getRegexResult(String sb,String regex){
        //String regex="<img src=\"([\\w\\s.:/]+?)\"";
        List<String> resultlist=new ArrayList<String>();
        Pattern p=Pattern.compile(regex);
        Matcher m=p.matcher(sb.toString());
        while(m.find()){
            resultlist.add(m.group(1));
        }
        return resultlist;
    }
}

 regex="<img\s*src=\"(.*)\";

获取group(1)即可