day 2021-10-30
学生信息管理系统要求实现学生信息的录入，并且实现增删改查等功能。
上代码：创建两个类
Student.java
package StudentManagementSystem;
public class Student {
private String sid;
private String name;
private String age;
private String address;
public Student() {} //使用alt+insert即可构造函数。这里是无参构造，选中的是目录。有参构造选中参数即可
public Student(String sid, String name, String age, String address) {
this.sid = sid;
this.name = name;
this.age = age;
this.address = address;
}
//生成get和set函数，alt+insert，构造getter和setter，shift选择需要范围即可
public String getSid() {
return sid;
}
public void setSid(String sid) {
this.sid = sid;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getAge() {
return age;
}
public void setAge(String age) {
this.age = age;
}
public String getAddress() {
return address;
}
public void setAddress(String address) {
this.address = address;
}
}
StudentManager.java
package StudentManagementSystem;
import java.util.ArrayList;
import java.util.Objects;
import java.util.Scanner;
public class StudentManager {
public static void main(String[] args) {
Menu();
}
public static void Menu() {
//创建集合对象用于存储学生数据
ArrayList array = new ArrayList<>();
while(true) {
System.out.println("======Welcome to the SMS======");
System.out.println("1. 添加学生");
System.out.println("2. 删除学生");
System.out.println("3. 修改学生");
System.out.println("4. 所有学生");
System.out.println("5. 退出程序");
System.out.println("请输入数字选择功能: ");
Scanner sc = new Scanner(System.in);
String select = sc.nextLine();
switch (select) {
case "1":
System.out.println("添加学生");
addStudent(array);
break;
case "2":
System.out.println("删除学生");
removeStudent(array);
break;
case "3":
System.out.println("修改学生");
updateStudent(array);
break;
case "4":
System.out.println("所有学生");
FindStudent(array);
break;
case "5":
System.out.println("感谢使用");
System.exit(0); //JVM exit
default:
System.out.println("请输入数字1--5选择功能");
}
}
}
public static void addStudent(ArrayList array) {
//录入学生数据
Scanner sc = new Scanner(System.in);
String sid;
while(true) {
System.out.println("请输入学生学号: ");
sid = sc.nextLine();
boolean flag = isUsed(array,sid);
if(flag) {
System.out.println("学号已被使用，请重新输入: ");
} else {
break;
}
}
System.out.println("请输入学生姓名: ");
String name = sc.nextLine();
System.out.println("请输入学生年龄: ");
String age = sc.nextLine();
System.out.println("请输入学生地址: ");
String address = sc.nextLine();
//创建学生对象
Student s = new Student();
s.setSid(sid);
s.setName(name);
s.setAge(age);
s.setAddress(address);
//添加到集合
array.add(s);
//添加成功提示
System.out.println("添加成功");
}
public static boolean isUsed(ArrayList array, String sid) {
boolean flag = false;
for (Student s : array) {
if (s.getSid().equals(sid)) {
flag = true;
break;
}
}
return flag;
}
public static void FindStudent(ArrayList array) {
//判断集合中是否有数据
if(array.size() ==0 ) {
System.out.println("目前没有学生，请添加后再查询");
} else{
//表头
System.out.println("学号ttt姓名tt年龄tt地址");
//遍历
for (Student s : array) {
System.out.println(s.getSid() + "t" + s.getName()
+ "t" + s.getAge() + "岁t" + s.getAddress());
}
}
}
public static void removeStudent(ArrayList array) {
Scanner sc = new Scanner(System.in);
System.out.println("请输入删除学生的学号: ");
String sid = sc.nextLine();
int index = -1;
for (int i = 0; i < array.size(); i ++) {
Student student = array.get(i);
if (student.getSid().equals(sid)) {
index = i;
break;
}
}
if(index == -1) {
System.out.println("学生不存在");
} else{
System.out.println("已找到该学生，是否继续？(y/n)");
String sign = sc.nextLine();
if(Objects.equals(sign, "y")) {
array.remove(index);
System.out.println("删除成功");
} else {
System.out.println("取消删除");
}
}
}
public static void updateStudent(ArrayList array) {
Scanner sc = new Scanner(System.in);
System.out.println("请输入需要修改学生的学号: ");
String sid = sc.nextLine();
//遍历
int index = -1;
int i = 0;
for ( ; i < array.size(); i ++) {
Student student = array.get(i);
if (student.getSid().equals(sid)) {
index = i;
break;
}
}
if(index == -1) {
System.out.println("学生不存在");
} else {
//录入修改信息
System.out.println("请输入新姓名：");
String name = sc.nextLine();
System.out.println("请输入新年龄：");
String age = sc.nextLine();
System.out.println("请输入新地址：");
String address = sc.nextLine();
//创建学生对象
Student s = new Student();
s.setSid(sid);
s.setName(name);
s.setAge(age);
s.setAddress(address);
array.set(i, s);
System.out.println("修改成功");
}
}
}
注意：此处判断用户输入的字符是否为“y”，这里不用“==”，使用Objects.equals(*, y)方法，用来比较字符串是否相等。其中*为用户设定的参数，即输入Scanner的变量。
其余暂不做解释，也没有文件操作和数据库的使用，请等待后续更新
