MaxNumString.java

public class MaxNumString {
    public int Continumax(String intputStr,  StringBuffer outputStr){
        int maxlength=0;
        StringBuffer maxNumberStr = null;

        int nowlength=0;
        StringBuffer nowNumberStr = null;


        for(int i=0;i<intputStr.length();i++){
            if((intputStr.charAt(i))>=48 && (intputStr.charAt(i))<=57){
                if(nowlength==0){
                    nowNumberStr = new StringBuffer(String.valueOf(intputStr.charAt(i)));
                    nowlength++;
                }else{

                    nowNumberStr.append(intputStr.charAt(i));
                    nowlength++;}

                if(nowlength>=maxlength){
                    maxNumberStr = nowNumberStr;
                    maxlength = nowlength;
                }
            }else{
                nowlength=0;
                nowNumberStr =null;
            }

        }

        System.out.println(maxNumberStr);
        return maxlength;
    }

    public static void main(String[]args) {
        MaxNumString test = new MaxNumString();

        System.out.println(test.Continumax("abcd12345ss54321", null));
        System.out.println(test.Continumax("abcd12345ed125ss123456789", null));
    }
}