File size: 2,565 Bytes
0284885 | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 | package case_package1;
import java.io.*;
import java.util.Scanner;
public class Login {
public static void main(String[] args) throws IOException {
/*
需求：写一个登录小案例
步骤：
将正确的用户名和密码手动保存在本地的userinfo.txt文件中
保存格式为：username=zhangsan&password=123&count=0
让用户键盘录入用户名和密码
比较用户录入的和正确的用户名密码是否一致
如果一致则打印登录成功
如果不一致则打印登录失败
*/
//1、读取正确的用户名和密码
BufferedReader br = new BufferedReader(new FileReader("/Users/zhaoxiaoyong/Documents" +
"/Java/IO_stream_project/Case_module/src/userinfo.txt"));
String line = br.readLine();
br.close();
// username=zhangsan&password=123&count=0
String[] userinfo = line.split("&");
String[] arr1 = userinfo[0].split("=");
String[] arr2 = userinfo[1].split("=");
String[] arr3 = userinfo[2].split("=");
String rightUsername = arr1[1];
String rightPassword = arr2[1];
int count = Integer.parseInt(arr3[1]);
//2、用户键盘录入用户名和密码
Scanner sc = new Scanner(System.in);
System.out.println("请输入用户名：");
String username = sc.nextLine();
System.out.println("请输入密码：");
String password = sc.nextLine();
//3、比较
if (rightUsername.equals(username) && rightPassword.equals(password) && count < 3) {
System.out.println("登录成功");
} else {
count++;
if (count < 3) {
System.out.println("登录失败，还剩下" + (3 - count) + "次机会");
} else {
System.out.println("用户账户被锁定");
}
writeInfo("username=" + rightUsername + "&password=" + rightPassword + "&count=" + count);
}
}
/*
* 作用：
* 写出一个字符串到本地文件中
* 参数：
* 要写的字符串
* */
private static void writeInfo(String content) throws IOException {
BufferedWriter bw = new BufferedWriter(new FileWriter("/Users/zhaoxiaoyong/Documents/Java" +
"/IO_stream_project/Case_module/src/userinfo.txt"));
bw.write(content);
bw.close();
}
}
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