学生管理系统

package 练习;

import java.util.Scanner;

import javax.swing.JOptionPane;

public class ATM1 {
    public static int xuehao[] = new int[10];
    public static String name[] = new String[10];
    public static int chengji[] = new int[10];
    public static int i = 0;

    public static void main(String[] args) {
        JOptionPane.showMessageDialog(null, "欢迎光临");
        String zhanghu = "123456";
        String mima = "123456";
        boolean iso = denglu(zhanghu, mima);
        if (iso) {
            while (true) {
                String b = JOptionPane.showInputDialog(null,
                        "1、添加\n2、显示\n3、删除\n4、修改\n5、排序\n6、查询\n7");
                int a = Integer.parseInt(b);
                switch (a) {
                case 1:
                    tianjia();
                    break;
                case 2:
                    xianshi();
                    break;
                case 3:
                    shanchu();
                    break;
                case 4:
                    xiugai();
                    break;
                case 5:
                    paixu();
                    break;
                case 6:
                    chaxu();
                    break;
                case 7:
                    System.exit(0);
                    ;
                    break;
                default:
                    JOptionPane.showMessageDialog(null, "只能输入1-7");
                }
            }
        }
    }
//查询 方法
    private static void chaxu() {
        int cz = chazhao();
        if (cz != -1) {
            JOptionPane.showMessageDialog(null, xuehao[cz] + name[cz]
                    + chengji[cz]);

        }
    }
//排序方法
    private static void paixu() {
        for (int n = 0; n < i; n++) {
            for (int j = n + 1; j < i; j++) {
                if (chengji[n] < chengji[j]) {
                    int s = chengji[n];
                    chengji[n] = chengji[j];
                    chengji[j] = s;
                    String xm = name[n];
                    name[n] = name[j];
                    name[j] = xm;
                    int xh = xuehao[n];
                    xuehao[n] = xuehao[j];
                    xuehao[j] = s;
                }
            }
        }
        xianshi();

    }
//修改方法
    private static void xiugai() {
        int n = chazhao();
        if (n != -1) {
            String str = JOptionPane.showInputDialog(null, "请输入修改的学号");
            String str1 = JOptionPane.showInputDialog(null, "请输入修改的姓名");
            String str2 = JOptionPane.showInputDialog(null, "请输入修改的成绩");
            xuehao[n] = Integer.parseInt(str);
            name[n] = str1;
            chengji[n] = Integer.parseInt(str2);
        }
    }
//删除方法
    private static void shanchu() {
        int s = chazhao();
        if (s != -1) {
            for (int n = s; n < i; n++) {
                xuehao[n] = xuehao[n + 1];
                name[n] = name[n + 1];
                chengji[n] = chengji[n + 1];
                i--;
            }
        }
    }
//显示方法
    private static void xianshi() {
        String info = "";
        for (int n = 0; n < i; n++) {
            info += xuehao[n] + name[n] + chengji[n] + "\n";
        }
        JOptionPane.showMessageDialog(null, info);
    }
//添加方法
    private static void tianjia() {
        String str = JOptionPane.showInputDialog(null, "请输入学号");
        String str1 = JOptionPane.showInputDialog(null, "请输入姓名");
        String str2 = JOptionPane.showInputDialog(null, "请输入成绩");
        xuehao[i] = Integer.parseInt(str);
        name[i] = str1;
        chengji[i] = Integer.parseInt(str2);
        i++;
    }
//登陆方法
    public static boolean denglu(String zhanghu, String mima) {
        for (int n = 3; n > 0; n--) {
            String str = JOptionPane.showInputDialog(null, "请输入账户");
            String str1 = JOptionPane.showInputDialog(null, "请输入密码");
            if (str.equals(str1) && str1.equals(str1)) {
                return true;
            }
            if (n == 1) {
                JOptionPane.showMessageDialog(null, "非法输入");
                return false;
            }
            JOptionPane.showMessageDialog(null, "你的输入有误，请重新输入" + (n - 1));
        }
        return false;
    }
//查找方法
    public static int chazhao() {
        int index = -1;
        String str = JOptionPane.showInputDialog(null, "请输入要查找的人");
        for (int n = 0; n < i; n++) {
            if (str.equals(name[n])) {
                return n;
            }
            JOptionPane.showMessageDialog(null, "查无此人");
        }
        return -1;
    }
}