学生查询系统

Student.java

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package yaoxia.java.studentsystem;

import java.util.List;


public class Student {
private String num;
private String name;
private int age;
private List<Integer> score;

public String getNum() {
return num;
}
public void setNum(String num) {
this.num = num;
}
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 List<Integer> getScore() {
return score;
}
public void setScore(List<Integer> score) {
this.score = score;
}
public String toString(){

for(Integer sco:this.getScore()){
System.out.println(sco);
}
return "name:"+this.getName()+"\tnum:"+this.getNum()+"\tage:"+this.age;

}

}

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StudentSystem.java

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package yaoxia.java.studentsystem;


import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;


public class StudentSystem {

Scanner input=new Scanner(System.in);
List<Student> stuList=new ArrayList<Student>();

public void start(){

System.out.println("1.录入学员信息");
System.out.println("2.根据学号查询学员信息");
System.out.println("3.修改学员信息");
System.out.println("4.根据学号删除学员信息");
System.out.println("5.统计学员平均考试成绩");
System.out.println("6.退出系统");


System.out.println("请选择菜单");
String choose=input.next();

if("1".equals(choose)){
save();
}else if("2".equals(choose)){
find();
}else if("3".equals(choose)){
change();
}else if("4".equals(choose)){
delete();
}else if("5".equals(choose)){
average();
}else if("6".equals(choose)){
System.out.println("欢迎下次使用，再见！");
System.exit(0);
}
else{
System.out.println("请输入正确的选项！");
start();
}

}

/**
* 统计学员平均考试成绩
*/
private void average() {
int sum=0;
int arg;
List<Integer> scores=new ArrayList<Integer>();

for(Student s:stuList){

scores=s.getScore();
int size=scores.size();

for(int  score:s.getScore()){
sum+=score;
}

arg=sum/size;
System.out.println(s.getName()+"\taverage:"+arg );
}
start();
}


/**
* 根据学号删除学员信息
*/
private void delete() {
System.out.println("请输入学号");
String num=input.next();

Student nowStudent=null;
for(Student stu:stuList){

if(num.equals(stu.getNum())){
nowStudent=stu;

}
}

if(nowStudent!=null){

stuList.remove(nowStudent);
System.out.println("删除成功！");
start();

}else{
System.out.println("no data!");
start();
}


}


/**
* 修改学员信息
*/
private void change() {

System.out.println("请输入学号");
String num=input.next();

Student nowStudent=null;
for(Student stu:stuList){

if(num.equals(stu.getNum())){
nowStudent=stu;

}
}

if(nowStudent!=null){

System.out.println("请输入姓名");
String name=input.next();


System.out.println("请输入年龄");
int age=input.nextInt();

int score;
String answer;
List<Integer> scores=new ArrayList<Integer>();
do{

System.out.println("请输入成绩");
score=input.nextInt();
scores.add(score);

System.out.println("是否继续 ,请选择(y / n)");
answer=input.next();

}while(!"n".equals(answer));

nowStudent.setName(name);
nowStudent.setAge(age);
nowStudent.setNum(num);
nowStudent.setScore(scores);

stuList.add(nowStudent);
start();
}else{
System.out.println("no data!");
start();
}


}

/**
* 根据学号查询学员信息
*/
private void find() {
System.out.println("请输入学号");
String num=input.next();

Student nowStudent=null;
for(Student stu:stuList){

if(num.equals(stu.getNum())){

nowStudent=stu;

break;

}

}

if(nowStudent!=null){

System.out.println(nowStudent);

}else{
System.out.println("no data!");
}



System.out.println("是否继续（y/n）");
String answer=input.next();

if("y".equals(answer)){
find();
}else{
start();
}

}



/**
* 录入学员信息
*/
private void save() {

System.out.println("请输入学号");
String num=input.next();

System.out.println("请输入姓名");
String name=input.next();

System.out.println("请输入年龄");
int age=input.nextInt();

String answer;
int score;

List<Integer> scores=new ArrayList<Integer>();
do{

System.out.println("请输入成绩");
score=input.nextInt();
scores.add(score);

System.out.println("是否继续 ,请选择(y / n)");
answer=input.next();

}while(!"n".equals(answer));

Student student=new Student();

student.setNum(num);
student.setName(name);
student.setAge(age);
student.setScore(scores);


stuList.add(student);

System.out.println("是否继续？（y/n）");
String answers=input.next();

if("y".equals(answers)){

save();
}else{
start();
}



}


}

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Test.java

****************************************************************************************************************************************************************************************************************************************************************************package yaoxia.java.studentsystem;


public class Test {


public static void main(String[] args) {

StudentSystem s=new StudentSystem();
s.start();

}

}