今天遇到个需求，需要从0000001开始计数，代码如下：

public class phone {
    public static void main(String[] args) throws IOException {
        FileWriter writer = new FileWriter(new File("C:\\Users\\mohe\\Desktop\\1.csv"));
       // int str =1000000;
        int aa=1;
        System.out.println();
        for (int i =0;i<=5000000;i++){
            int a=aa+i;
            writer.write(new DecimalFormat("0000000").format(a)+"\n");
            //格式化数字位数，缺的自动补全0后写入文件里，“\n”是换行符
        }
        writer.close();
    }
    }