今天是简单的java小测验，实现简单的增删改查操作。我先用数组完成。
后面的话想实现连接数据库的增删改查，但是始有bug不知道咋改，写的少不清楚问题出在哪，多写几回应该就能对症下药。
下面是数组的代码
Student类
public class Student {
String stunumber;
String name;
int age;
boolean sex;
double score;
public Student(String stunumber, String name, int age, boolean sex, double score) {
this.stunumber = stunumber;
this.name = name;
this.age = age;
this.sex = sex;
this.score = score;
}
public Student() {
}
public String getStunumber() {
return stunumber;
}
public void setStunumber(String stunumber) {
this.stunumber = stunumber;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
public boolean isSex() {
return sex;
}
public void setSex(boolean sex) {
this.sex = sex;
}
public double getScore() {
return score;
}
public void setScore(double score) {
this.score = score;
}
}
StudentManager
import java.util.Scanner;
public class StudentManager {
Student student[] = new Student[999];
int sum = 0;
void page() {
Scanner sc = new Scanner(System.in);
int k = 1;
while (k == 1) {
System.out.println("1、遍历输出学生信息；");
System.out.println("2、新学生信息录入；");
System.out.println("3、删除学生信息；");
System.out.println("4、修改学生信息；");
System.out.println("5、查询学生信息；");
switch (sc.nextInt()) {
case 1: {
showStudnet();
break;
}
case 2: {
addStudent();
break;
}
case 3: {
deleteStudent();
break;
}
case 4: {
updateStudent();
break;
}
case 5: {
selectStudnet();
break;
}
case 6: {
k = 0;
}
}
}
}
void showStudnet()
{
if(sum==0)
System.out.println("目前没有学生信息");
for(int i=0;i<sum;i++) {
if (student[i].stunumber != null) {
System.out.println("学号" + student[i].stunumber);
System.out.println("姓名" + student[i].name);
System.out.println("年龄" + student[i].age);
if (student[i].sex)
System.out.println("性别 女");
else
System.out.println("性别 男");
System.out.println("成绩" + student[i].score);
}
}
}
void addStudent ()
{
Scanner sc = new Scanner(System.in);
int x = 1;
String stunumber="123";
while (x == 1)
{
System.out.println("请输入学号");
stunumber = sc.nextLine();
x=0;
for (int i = 0; i < sum; i++) {
if (stunumber.equals(student[i].getStunumber())) {
System.out.println("请重新输入，有学号相同的学生");
x=1;
break;
}
else
{
x=0;
}
}
}
String name;
int age;
boolean sex;
double score;
System.out.println("请输入姓名");
name = sc.nextLine();
System.out.println("请输入年龄");
age = sc.nextInt();
System.out.println("请输入性别,男生false，女生true");
sex=sc.nextBoolean();
System.out.println("请输入分数");
score = sc.nextDouble();
student[sum]=new Student();
student[sum].setName(name);
student[sum].setAge(age);
student[sum].setScore(score);
student[sum].setSex(sex);
student[sum].setStunumber(stunumber);
sum++;
System.out.println("添加成功");
}
void deleteStudent()
{
Scanner sc = new Scanner(System.in);
System.out.println("输入要删除的学号");
String stunumber = sc.nextLine();
int k=10;
for (int i = 0; i < sum; i++) {
if (stunumber.equals(student[i].getStunumber())) {
student[i].setStunumber(null);
System.out.println("删除成功");
k=1;
break;
}
}
if(k==10)
System.out.println("该学号不存在");
}
void updateStudent()
{
Scanner sc = new Scanner(System.in);
System.out.println("输入要修改的学号");
int k=10;
String stunumber = sc.nextLine();
for (int i = 0; i < sum; i++) {
if (stunumber.equals(student[i].getStunumber())) {
String name;
int age;
boolean sex;
double score;
System.out.println("请输入姓名");
name = sc.nextLine();
System.out.println("请输入年龄");
age = sc.nextInt();
System.out.println("请输入性别,男生false，女生true");
sex=sc.nextBoolean();
System.out.println("请输入分数");
score = sc.nextDouble();
student[i].setName(name);
student[i].setAge(age);
student[i].setScore(score);
student[i].setSex(sex);
student[i].setStunumber(stunumber);
System.out.println("修改成功");
k=1;
break;
}
}
if(k!=1)
System.out.println("该学号不存在");
}
void selectStudnet()
{
Scanner sc = new Scanner(System.in);
System.out.println("输入要查询的学号");
int k=10;
String stunumber = sc.nextLine();
for (int i = 0; i < sum; i++) {
if (stunumber.equals(student[i].getStunumber())) {
if (student[i] != null) {
System.out.println("学号" + student[i].stunumber);
System.out.println("姓名" + student[i].name);
System.out.println("年龄" + student[i].age);
if (student[i].sex)
System.out.println("性别 女");
else
System.out.println("性别 男");
System.out.println("成绩" + student[i].score);
k=1;
}
}
}
if(k!=1)
System.out.println("该学号不存在");
}
}
main函数
public class Main {
public static void main(String[] args) {
StudentManager manager = new StudentManager();
manager.page();
}
}