Random-随机生成电话号

 package test1;

 import java.io.BufferedWriter;
 import java.io.FileWriter;
 import java.io.IOException;
 import java.util.Random;

 public class ranDomTest1 {
     public static void main(String[] args) throws  IOException{
 //        test();
         test2();
     }

     public static void test2() throws IOException{
         FileWriter fw = new FileWriter("codeId189.txt");
         //创建一个缓存中，并发fw作为一个对象传入缓冲区中
         BufferedWriter bw = new BufferedWriter(fw);
         //9 代表循环9次，生成9个随机数
         for (int j=0;j<700;j++)
         {
             String number = "189";
             Random rd = new Random();
             for (int i=0;i<8;i++)//
             {
                 //生成9为随机数
                 number += rd.nextInt(9);
             }
             bw.write(number);
             bw.newLine();
             bw.flush();
 //            System.out.println(number);
         }
         //刷新缓冲区
         bw.flush();
         //关闭缓冲区，其实就是关闭缓存流对下岗
         bw.close();
     }

     public static void test() {
         StringBuilder str =new StringBuilder("");
         Random random = new Random();
         for (int i=0;i<8;i++)
         {
             str.append(random.nextInt(10));
         }
         System.out.println("133"+str.toString());
     }
 }