第十三章 带参方法 模拟学生信息登记,实现查询,录入,修改学生信息

package cn.jbit.test.yang;public class testDudu {public static void main(String[] args) {Dudu dudu = new Dudu();// 将测试类实例化dudu.Show1();// 调用整个大方法}}package cn.jbit.test.yang;import java.util.Scanner;public class Dudu {// 测试类Scanner input = new Scanner(System.in);Clazz cla = new Clazz();Student students;private void Show() {// 初始化菜单System.out.println("1.学生信息       2.添加学生      3.修改姓名         4.退出");System.out.println("请选择您需要办理的业务：");}public void Show1() {Show();int a;do {a = input.nextInt();switch (a) {case 1:System.out.println("1.学生信息");cla.ShowStudents();// 调用学生信息方法System.out.println("\t");Show();break;case 2:System.out.println("2.添加学生");char c = 'y';// 判断是否录入学生信息while (c == 'y') {students = new Student();// 将学生类实例化System.out.println("请输入学生姓名");students.name = input.next();System.out.println("请输入学生年龄");students.age = input.nextInt();cla.AddStudent(students);// 调用添加学生方法System.out.println("是否继续录入(y继续,输入y以外任意字符结束录入)");c = input.next().charAt(0);}System.out.println("\t");Show();break;case 3:System.out.println("3.修改姓名");cla.ShowStudents();// 调用学生信息方法System.out.println("请输入需要修改名字的学生编号");int id = input.nextInt();System.out.println("请输入要修改的名字");String name = input.next();String result = cla.Rename(id, name);// 判断名字是否修改成功System.out.println(result);cla.ShowStudents();// 调用学生信息方法System.out.println("\t");Show();break;case 4:students = new Student();students.name = "";students.age = 0;students.id = 0;System.out.println("系统退出");return;default:System.out.println("您的输入有误,请输入1到4任意整数");break;}} while (!"0".equals(a));}}package cn.jbit.test.yang;public class Clazz {// 班级类public Student[] students = new Student[20];// 将学生类实例化public void AddStudent(Student student) {// 添加学生方法for (int i = 0; i < students.length; i++) {if (students[i] == null) {students[i] = student;student.id = GetID();break;}}}public int GetID() {// 学生id方法int max = 0;for (int i = 0; i < students.length; i++) {if (students[i] != null && max < students[i].id) {max = students[i].id;}}if (max == 0) {return 1001;} else {return max + 1;}}public void ShowStudents() {// 学生信息方法boolean yang = false;for (int i = 0; i < students.length; i++) {if (students[i] != null) {yang = true;students[i].Show();}}if (yang == false) {System.out.println("还未开班");}}public String Rename(int id, String name) {// 修改学生姓名方法for (int i = 0; i < students.length; i++) {if (students[i] != null && id == students[i].id) {students[i].name = name;return "名字修改成功";}}return "修改失败";}}package cn.jbit.test.yang;public class Student {// 学生类public String name;// 学生姓名public int age;// 学生年龄public int id;// 学生idpublic void Show() {// 学生信息显示方法System.out.println("姓名：" + name + "\t" + "年龄：" + "\t" + age + "学号是："+ id);}}