用java将字符串中的数字输出

比如字符串str = aaa23aa12323dsafb23213

输出   231232323213

import java.util.regex.Matcher;
import java.util.regex.Pattern;

String str = "aaa23aa12323dsafb23213";
  Pattern pattern = Pattern.compile("\\d+");
     Matcher matcher = pattern.matcher(str);
     while(  matcher.find()){
        System.out.println(matcher.group());
     }

在这里牵扯到两个类Pattern跟Matcher  正则表达式   详情请看API