同时使用scanner, bufferedreader，无法接着debug

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.util.Scanner;

public class B1031 {
    public static void main(String[] args) throws Exception {
        BufferedReader rd = new BufferedReader(new InputStreamReader(System.in));
        Scanner in = new Scanner(System.in);
        int N = in.nextInt();
        int []flag = new int[N];
        int sum = 0;
        int count = 0;
        int passed = 0;
        for (int i = 0; i < N; i++)
        {
            flag[i] = 0;            
        } /*判断每一行是否合格，合格为1, 不合格为0 */

        int []weight = {7, 9, 10, 5, 8, 4, 2, 1, 6, 3, 7, 9, 10, 5, 8, 4, 2};   
        char [] ch = {'1', '0', 'X', '9', '8', '7', '6', '5', '4', '3', '2'};
        while (count < N)
        {
            String s = rd.readLine();
            for (int x = 0; x < s.length(); x++)
            {
                 /*将含有X的错误身份证号输出*/
                if (s.charAt(x) == 'X')
                {
                    System.out.print(s);
                    break;                  
                }

                if (s.length() < 18 || s.length() > 18)
                {
                    System.out.print(s);
                    break;
                }           
                sum += (s.charAt(x) - '0') * weight[x];         
            }

            if ((s.charAt(17) - '0') == ch[sum % 11] || s.charAt(17) == ch[sum % 11])
            {
                flag[count] = 1;                
            }
            count++;        
        }

        for (int z = 0; z < N; z++)
        {
            if (flag[z] != 1)
            {           
                break;
            }
            else
            {
                passed++;           
            }
        }
        if (passed == N)
        {
            System.out.print("All passed");
        }
        in.close();
    }
}

debug到rd.readline（）无法点击下一步

scanner会阻塞住程序，等待输入，因而无法触发断点，你只要正常输入，再回车就可以了。

关于你的问题，参考这个程序：http://blog.csdn.net/qq_34594236/article/details/51694930

没有输入内容，readline（）方法不会执行，输入或不输入按回车才能执行完readline（）方法，回车是结束符