Java第二次测试代码：

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 char isFM() {
    if (sex)
        return 'M';
    else
        return 'F';
}
public String getStunumber() {
    return stunumber;
}

public String getName() {
    return name;
}

public int getAge() {
    return age;
}

public boolean isSex() {
    return sex;
}

public double getScore() {
    return score;
}

public void setStunumber(String stunumber) {
    this.stunumber = stunumber;
}

public void setName(String name) {
    this.name = name;
}

public void setAge(int age) {
    this.age = age;
}

public void setSex(boolean sex) {
    this.sex = sex;
}

public void setScore(double score) {
    this.score = score;
}

}
import java.util.Objects;

public class StudentManager {
private Student[] students;
public int index;

public StudentManager(){
    students=new Student[10];
    index=0;
}
public void showStudent(){
    for(int i=0;i<index;i++) {
        System.out.println(students[i].getStunumber()+"\t"+students[i].getName()+"\t"+students[i].getAge()+"\t"+students[i].isFM()+"\t"+students[i].getScore());
    }
}
public void addStudent(String stunumber,String name,int age,boolean sex,double score){
    for(int i=0;i<index;i++){
        if(Objects.equals(stunumber, students[i].getStunumber())){
            System.out.println("学号重复，请重新选择！");
            return;
        }
    }
    students[index]=new Student(stunumber,name,age,sex,score);
    index++;
}
public void deleteStudent(String stunumber){
    int flag=0;
    for(int i=0;i<index;i++){
        if(Objects.equals(stunumber, students[i].getStunumber())){
            flag=1;
            for(int j=i;j<index;j++){
                if(j<index-1){
                    students[j].setStunumber(students[j+1].getStunumber());
                    students[j].setName(students[j=1].getName());
                    students[j].setSex(students[j+1].isSex());
                    students[j].setAge(students[j+1].getAge());
                    students[j].setScore(students[j+1].getScore());
                }
                else if(j==index-1){
                    students[j].setStunumber(null);
                    students[j].setName(null);
                    students[j].setSex(true);
                    students[j].setAge(0);
                    students[j].setScore(0);
                }
            }
            index--;
        }
    }
    if(flag==0)
        System.out.println("学号不存在，请重新选择！");
}
public void updateStudent(String stunumber,String name,int age,boolean sex,double score){
    int flag=0;
    for(int i=0;i<index;i++){
        if(Objects.equals(stunumber, students[i].getStunumber())){
            students[i].setStunumber(stunumber);
            students[i].setName(name);
            students[i].setAge(age);
            students[i].setSex(sex);
            students[i].setScore(score);
            flag=1;
        }
    }
    if(flag==0)
        System.out.println("学号不存在，请重新选择！");
}
public void selectStudent(String stunumber){
    int flag=0;
    for(int i=0;i<index;i++){
        if(Objects.equals(stunumber, students[i].getStunumber())){
            flag=1;
            System.out.println(students[i].getStunumber()+"\t"+students[i].getName()+"\t"+students[i].getAge()+"\t"+students[i].isFM()+"\t"+students[i].getScore());
        }
    }
    if(flag==0)
        System.out.println("学号不存在，请重新选择！");
}
public void menu(){
    System.out.println("***************************************************************");
    System.out.println("石家庄铁道大学软件工程系学生信息管理系统");
    System.out.println("***************************************************************");
    System.out.println("1、\t遍历输出学生信息:");
    System.out.println("2、\t新学生信息录入:");
    System.out.println("3、\t删除学生信息:");
    System.out.println("4、\t修改学生信息:");
    System.out.println("5、\t查询学生信息:");
    System.out.println("***************************************************************");
    System.out.println("请选择：");

}

}
import java.util.Scanner;

public class test {
public static void main(String[] args) {
Scanner sc=new Scanner(System.in);
String stunumber;String name;int age;boolean sex;double score;
StudentManager manager=new StudentManager();
while (true){
int choice;
manager.menu();
choice=sc.nextInt();
switch (choice){
case 1:
manager.showStudent();
break;
case 2:
stunumber=sc.next();
name=sc.next();
age=sc.nextInt();
sex=sc.nextBoolean();
score=sc.nextDouble();
manager.addStudent(stunumber,name,age,sex,score);
break;
case 3:
stunumber=sc.next();
manager.deleteStudent(stunumber);
break;
case 4:
stunumber=sc.next();
name=sc.next();
age=sc.nextInt();
sex=sc.nextBoolean();
score=sc.nextDouble();
manager.updateStudent(stunumber,name,age,sex,score);
break;
case 5:
stunumber=sc.next();
manager.selectStudent(stunumber);
break;
default:
return;
}
}
}
}