还是错了，求助

Question

 import java.util.Arrays;

import java.util.Calendar;

import java.util.Date;

   interface Iqianqian{

   void methodone();

void methodFour();

void methodTwo();

void methodThree();

void methodfour();

 }

public   class Helloqianqian {

 public static void main(String[] args) {

 Iqianqian qq= new tender();

 System.out.println("功能1"+" ");

 qq.methodone();

 System.out.println("功能2"+" ");

 qq.methodTwo();

 System.out.println("功能3"+" ");

 qq.methodThree();

 System.out.println("功能4"+" ");

 qq.methodfour();

}

public   class tender implements Iqianqian{

public void methodOne() {

        Calendar Q = Calendar.getInstance();

        Date date = Q.getTime();

        Long time = Q.getTimeInMillis();

        int year = Q.get(Calendar.YEAR);

        int month = Q.get(Calendar.MONTH) + 1;

        int day = Q.get(Calendar.DAY_OF_MONTH);

        int hour = Q.get(Calendar.HOUR_OF_DAY);

        int minute = Q.get(Calendar.MINUTE);

        int second = Q.get(Calendar.SECOND);

        System.out.println("您好北京时间；" + date);

        System.out.println("小Q报时；" + year + "年" + month + "月" + day + "  " + hour + "；" + minute + "；" + second);

        System.out.println("毫秒数； " + time);

    }

 

    @Override

    public void methodTwo() {

        String Q = " Hello lan qian is a good girl  ";

        System.out.println("字符串长度：" + Q.length());

        System.out.println("转换为大写：" + Q.toUpperCase());

        System.out.println("子串为：" + Q.substring(6, 30));

        String q1 = Q.replace("good", "beatuiful");

        System.out.println("替换为：" + Q.replace("good", "beatuiful"));

        System.out.println("删除字符串两边多余的空格：" + Q.trim());

        System.out.println("qian的位置: " + Q.indexOf("qian"));

        String[] arr = Q.split(" ");

        System.out.println("把空格拆成数组 ； " + Arrays.toString(arr));

        byte[] q2 = Q.getBytes();

        System.out.print("转换为字节数数组： ");

        for (int i = 0; i < q2.length; i++) {

            System.out.print(q2[i] + " ");

        }

    }

 

    @Override

    public void methodThree() {

        int[] Q = new int[20];

        for (int i = 1; i < 20; i++) {

            Q[i] = (int) (Math.random() * 100+1);

            Arrays.sort(Q);

            System.out.println("排序后的数;" +Q[i] + " ");

        }

    }

 

    @Override

    public void methodFour() {

        int score = 110;

        Integer englishscore = new Integer(score);

        String str = "108";

        int mathscore = Integer.valueOf(str);

        double chinesescore = englishscore.doubleValue();

        int sum = (int) (mathscore + score + chinesescore);

        int averge = (sum / 3);

        System.out.println("三门课总成绩；" + sum);

        System.out.println("三门课平均成绩；" + averge);

    }

 

    double doubleValue() {

        return 0;

    }

 

    int valueOf(String str) {

        return 0 ;

    }

@Override

public void methodone() {

// TODO Auto-generated method stub

}

@Override

public void methodfour() {

// TODO Auto-generated method stub

}

    

}

}