谁给个学生信息管理系统java的

package com.star.studentmg;import java.util.ArrayList;public class MethodClass {
    public static void showTitleMenu() {
        System.out.println("******学生管理系统******");
        System.out.println("1.登录");
        System.out.println("2.注册");
        System.out.println("3.退出");
    }
    public static void showAllStudentInfo(ArrayList<Student> stuAry) {
        for(Student s : stuAry){
            System.out.println(s);
        }
    }
    public static void showAllStudentSid(ArrayList<Student> stuAry,int sid) {
         for(Student s : stuAry){
             if(sid==s.getSid())
             System.out.println(s);
            }
    }
    public static boolean checkStudentNum(ArrayList<Student> stuAry, int sid) {
        boolean bl = false;
        for (Student stu : stuAry) {
                if (sid==stu.getSid()) {
                    bl = true;
                    break;
                }
        }
        return bl;
    }
    public static boolean checkUserNum(ArrayList<User> userAry, String uname) {
        boolean bl = false;
        for (User user : userAry) {
                if (uname.equals(user.getUname())) {
                    bl = true;
                    break;
                }
        }
        return bl;
    }    public static void putUser(ArrayList<User> userAry, User user) {
        userAry.add(user);
    }    public static void putStudent(ArrayList<Student> stuAry, Student stu) {
        stuAry.add(stu);
    }
    public static boolean checkUser(ArrayList<User> userAry, User user) {
        boolean flag = false;
        for (int i = 0; i < userAry.size(); i++) {
                if ((userAry.get(i).getUname().equals(user.getUname())) &&
                    (userAry.get(i).getUpass().equals(user.getUpass()))) {
                    flag = true;
                    break;
                }
        }
        return flag;
    }    public static int findStudentById(ArrayList<Student> stuAry, int sid){
      for(int i=0;i<stuAry.size();i++){
          if(stuAry.get(i).getSid()==sid){
              return i;
          }
      }
      return -1;
  }  public static void deleteStudent(ArrayList<Student> stuAry,int sid){
      int findIndex = findStudentById(stuAry, sid);
      if (findIndex != -1) {
          stuAry.remove(findIndex);
      } else {
          System.out.println("没有此人！");
      }
  }    public static void showMainMenu() {
        System.out.println("*****************************");
        System.out.println("******欢迎进入学生管理系统******");
        System.out.println("*****************************");
        System.out.println("**         1.添加学生信息    **");
        System.out.println("**         2.删除学生信息    **");
        System.out.println("**         3.修改学生信息    **");
        System.out.println("**         4.查询学生信息    **");
        System.out.println("**         5.重登录         **");
        System.out.println("**         6.退出系统       **");
        System.out.println("*****************************");
        System.out.println("*****************************");
    }}package com.star.studentmg;public class Student {
    private String sname;
    private int sid;
    private double yScore;
    private double eScore;
    private double mScore;
    Student(int sid, String sname, double yScore, double eScore, double mScore) {
        this.sid = sid;
        this.sname = sname;
        this.yScore = yScore;
        this.eScore = eScore;
        this.mScore = mScore;
    }    public void setSname(String sname) {
        this.sname = sname;
    }    public String getSname() {
        return sname;
    }    public void setSid(int sid) {
        this.sid = sid;
    }    public int getSid() {
        return sid;
    }    public void setYscore(double s) {
        yScore = s;
    }    public double getYscore() {
        return yScore;
    }    public void setEscore(double s) {
        eScore = s;
    }    public double getEscore() {
        return eScore;
    }    public void setMscore(double s) {
        mScore = s;
    }    public double getMscore() {
        return mScore;
    }
    public String toString(){
        return "学号："+sid+",姓名："+sname+",语文成绩："+yScore+",英语成绩："+eScore+",数学成绩："+mScore;
    }
}

package com.star.studentmg;import java.util.Scanner;
import java.util.ArrayList;class Test {    public static ArrayList<Student> stuList = new ArrayList<Student>();//存放全部学生对象的容器
    public static ArrayList<User> userAry = new ArrayList<User>();//存放全部用户对象的容器
    public static Scanner sc = new Scanner(System.in);    public static void main(String[] args) {
        /////////////和用户信息相关的变量///////////
        String uname = "";
        String upass = "";
        String rpass = "";
        /////////////和学生信息相关的变量///////////
        int sid = 0;
        String sname = "";
        double yScore = 0;
        double eScore = 0;
        double mScore = 0;
        /////////////////////////////////////////
        String flag = "";//用于表示是/否判断的变量（比如是否退出系统？(Y/N)）
        int sel = -1;//用于接受用户的输入选择，供switch语句使用
        flag1:while (true) {
            MethodClass.showTitleMenu();
            switch ((sel = sc.nextInt())) {
            case 1:
                sc.nextLine();
                System.out.println("******用户登录******");
                System.out.println("用户名：");
                uname = sc.nextLine();
                System.out.println("密码：");
                upass = sc.nextLine();
                User tempUser = new User(uname, upass);
                if (MethodClass.checkUser(userAry, tempUser)) {
                    flag3:while (true) {
                        MethodClass.showMainMenu();
                        switch ((sel = sc.nextInt())) {
                        case 1:
                            sc.nextLine();
                            System.out.println("******学生信息录入******");
                            System.out.println("编号：");
                            sid = sc.nextInt();
                            System.out.println("姓名：");
                            sc.nextLine();
                            sname = sc.nextLine();
                            System.out.println("语文成绩：");
                            yScore = sc.nextDouble();
                            System.out.println("英语成绩：");
                            eScore = sc.nextDouble();
                            System.out.println("数学成绩：");
                            mScore = sc.nextDouble();
                            if (!MethodClass.checkStudentNum(stuList, sid)) {
                            Student   stuTemp  = new Student(sid, sname,
                                        yScore, eScore, mScore);
                                MethodClass.putStudent(stuList, stuTemp);
                                System.out.println("学生信息录入成功！");
                                continue flag3;
                            } else {
                                System.out.println("已存在此学生编号！");
                                continue flag3;
                            }
                        case 2:
                            sc.nextLine();
                            System.out.println("******学生信息删除******");
                            System.out.println("请输入删除的学生编号：");
                            sid=sc.nextInt();
                            MethodClass.deleteStudent(stuList,sid);
                            System.out.println("删除成功！");
                            break;
                        case 3:
                           sc.nextLine();
                           System.out.println("******学生信息修改******");
                           System.out.println("请输入学生编号：");
                           sid = sc.nextInt();
                           System.out.println("姓名：");
                           sc.nextLine();
                           sname = sc.nextLine();
                           System.out.println("语文成绩：");
                           yScore = sc.nextDouble();
                           System.out.println("英语成绩：");
                           eScore = sc.nextDouble();
                           System.out.println("数学成绩：");
                           mScore = sc.nextDouble();
                           Student stuTemp = new Student(sid, sname, yScore, eScore, mScore);
                           MethodClass.deleteStudent(stuList,sid);
                           MethodClass.putStudent(stuList, stuTemp);
                           System.out.println("修改成功！");
                            break;
                        case 4:
                            sc.nextLine();
                            System.out.println("******学生信息查询******");
                            System.out.println("***1.查询全部学生信息***");
                            System.out.println("***2.按学生编号查询*****");
                            System.out.println("***3.返回主页面*********");
                            switch ((sel = sc.nextInt())) {
                            case 1:
                                MethodClass.showAllStudentInfo(stuList);
                                break;
                            case 2:
                                System.out.println("请输入查询的学生编号：");
                                sid=sc.nextInt();
                               MethodClass.showAllStudentSid(stuList,sid);                                break;
                            case 3:
                                System.out.println("真的要返回主页么？(Y/N)");
                                sc.nextLine();
                                flag = sc.nextLine();
                                if (flag.equals("Y") || flag.equals("y")) {
                                    continue flag3;
                                }
                                break;
                            default:
                                System.out.println("请输入1~2的数字！");
                            }
                            break;
                        case 5:
                            System.out.println("确实要重登录吗？(Y/N)");
                            sc.nextLine();
                            flag = sc.nextLine();
                            if (flag.equals("Y") || flag.equals("y")) {
                                continue flag1;
                            }
                            break;
                        case 6:
                            System.out.println("真的要退出么？(Y/N)");
                            sc.nextLine();
                            flag = sc.nextLine();
                            if (flag.equals("Y") || flag.equals("y")) {
                                System.exit(0);
                            }
                            break;
                        default:
                            System.out.println("请输入1~5之间的数！");                        }
                    }
                } else {
                    System.out.println("用户名或密码错误！");
                    continue flag1;
                }
            case 2:
                sc.nextLine();
                flag2:
                        while (true) {                    System.out.println("******用户注册******");
                    System.out.println("用户名：");
                    uname = sc.nextLine();
                    System.out.println("密码：");
                    upass = sc.nextLine();
                    System.out.println("确认密码：");
                    rpass = sc.nextLine();
                    if (!MethodClass.checkUserNum(userAry, uname)) {
                        if (upass.equals(rpass)) {
                            User tempUser2 = new User(uname, upass);
                            MethodClass.putUser(userAry, tempUser2);
                            System.out.println("注册成功！请在主页面登录。");
                            continue flag1;
                        } else {
                            System.out.println("两次密码输入不一致！  需要重新注册么？(Y/N)");
                            flag = sc.nextLine();
                            if (flag.equals("Y") || flag.equals("y")) {
                                continue flag2;
                            } else {
                                continue flag1;
                            }
                        }
                    } else {
                        System.out.println("已存在此用户！  需要重新注册么？(Y/N)");
                        flag = sc.nextLine();
                        if (flag.equals("Y") || flag.equals("y")) {
                            continue flag2;
                        } else {
                            continue flag1;
                        }                    }                }
            case 3:
                System.out.println("真的要退出么？(Y/N)");
                sc.nextLine();
                flag = sc.nextLine();
                if (flag.equals("Y") || flag.equals("y")) {
                    System.exit(0);
                }
                break;
            default:
                System.out.println("请输入1~3之间的数！");            }        }    }
}
package com.star.studentmg;
public class User {
    private String uname;
    private String upass;
    User(String name, String pass) {
        uname = name;
        upass = pass;
    }    public void setUname(String name) {
        uname = name;
    }    public String getUname() {
        return uname;
    }    public void setUpass(String pass) {
        upass = pass;
    }    public String getUpass() {
        return upass;
    }
}

使用了典型的Service, Dao, Bean来进行操作
package test;import java.io.IOException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Scanner;public class StudentManageSystem {
    // StudentManager中提供的操作菜单
    public static void showServices() {
        System.out.println("----------------功能菜单------------------");
        System.out.println("******** 0. 退出管理操作");
        System.out.println("******** 1. 显示学生信息");
        System.out.println("******** 2. 查询学生");
        System.out.println("******** 3. 添加学生");
        System.out.println("******** 4. 删除学生");
        System.out.println("------------------结束------------------");
        System.out.println();
    }    // 管理学生
    public void manageStudents() throws IOException {
        Scanner scanner = new Scanner(System.in);
        StudentDao sd = new StudentDao();
        StudentService ss = new StudentService(sd, scanner);        showServices();
        int op = -1;        while (op != 0) {
            System.in.skip(System.in.available());
            System.out.print("输入菜单编号: ");
            op = scanner.nextInt();
            scanner.nextLine(); // 吃掉输入菜单编号后无效的回车字符            switch (op) {
            case 0:
                break;
            case 1:
                ss.showStudents();
                break;
            case 2:
                ss.findStudent();
                break;
            case 3:
                ss.addStudent();
                break;
            case 4:
                ss.removeStudent();
                break;
            case 5:
                showServices();
                break;
            default:
                System.out.println("没有提供此项操作\n");
            }
        }    }    public static void main(String[] args) throws IOException {
        StudentManageSystem sm = new StudentManageSystem();
        sm.manageStudents();
    }
}class StudentService {
    private StudentDao studentDao;
    private Scanner scanner;    public StudentService(StudentDao studentDao, Scanner scanner) {
        this.studentDao = studentDao;
        this.scanner = scanner;
    }    // 添加学生
    public void addStudent() {
        System.out.print("输入学生资料进行添加: ");
        String name = scanner.nextLine();
        // 这里只处理了学生信息只有姓名
        // 可以做复杂一点，例如输入学生的学号，姓名，班级等
        Student s = new Student(name);
        studentDao.addStudent(s);
        System.out.println("添加成功\n");
    }    public void removeStudent() {
        System.out.print("输入学生姓名进行删除: ");
        String name = scanner.nextLine();
        Student s = studentDao.findStudent(name);        if (s == null) {
            System.out.println("查无此学生");
        } else {
            studentDao.removeStudent(s);
            System.out.println("已经删除学生: " + s);
        }
        System.out.println();
    }    // 查找学生
    public void findStudent() {
        System.out.print("输入学生姓名进行查询: ");
        String name = scanner.nextLine();
        Student s = studentDao.findStudent(name);
        if (s == null) {
            System.out.println("查无此学生");
        } else {
            System.out.println("搜索查找到的学生: " + s);
        }
        System.out.println();
    }    // 显示已经有的学生信息
    public void showStudents() {
        List<Student> students = studentDao.getStudents();        if (students.size() == 0) {
            System.out.println("列表中还没有任何学生");
        } else {
            System.out.println("========学生信息:");
        }        for (Student s : students) {
            System.out.println(s);
        }        System.out.println();
    }
}// 对学生数据进行执久化操作
class StudentDao {
    private List<Student> students;    public StudentDao() {
        students = new ArrayList<Student>();
    }    // 添加学生
    public void addStudent(Student student) {
        students.add(student);
    }    // 删除学生
    public void removeStudent(Student student) {
        students.remove(student);
    }    // 使用学生的名字查找进行查找
    public Student findStudent(String name) {
        for (Student s : students) {
            if (s.getName().equals(name)) { return s; }
        }        return null;
    }    // 返回学生列表的视图，不可修改
    public List<Student> getStudents() {
        return Collections.unmodifiableList(students);
    }
}class Student {
    private String name;    public Student() {
    }    public Student(String name) {
        this.name = name;
    }    public String getName() {
        return name;
    }    public void setName(String name) {
        this.name = name;
    }    @Override
    public String toString() {
        return "Name: " + name;
    }
}

*^_^*，没事又改了下
package test;import java.io.IOException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Scanner;public class StudentManageSystem {
    // StudentManager中提供的操作菜单
    public static void showMenus() {
        String format = "              %s\n";
        System.out.println("----------------功能菜单------------------");
        System.out.printf(format, "0. 退出管理");
        System.out.printf(format, "1. 显示学生");
        System.out.printf(format, "2. 查询学生");
        System.out.printf(format, "3. 添加学生");
        System.out.printf(format, "4. 删除学生");
        System.out.printf(format, "5. 功能菜单");
        System.out.println("-------------------结束------------------");
        System.out.println();
    }    // 管理学生
    public void manageStudents() throws IOException {
        Scanner scanner = new Scanner(System.in);
        StudentDao sd = new StudentDao();
        StudentService ss = new StudentService(sd, scanner);        showMenus();
        int op = -1;        while (op != 0) {
            System.in.skip(System.in.available());
            System.out.print("输入菜单编号: ");
            op = scanner.nextInt();
            scanner.nextLine(); // 吃掉输入菜单编号后无效的回车字符            try {
                switch (op) {
                case 0:
                    break;
                case 1:
                    ss.showStudents();
                    break;
                case 2:
                    ss.findStudent();
                    break;
                case 3:
                    ss.addStudent();
                    break;
                case 4:
                    ss.removeStudent();
                    break;
                case 5:
                    showMenus();
                    break;
                default:
                    System.out.println("没有提供此项操作\n");
                }
            } catch (Exception e) {
                System.out.println("\t" + e.getMessage() + "\n");
            }
        }
    }    public static void main(String[] args) throws IOException {
        StudentManageSystem sm = new StudentManageSystem();
        sm.manageStudents();
    }
}class StudentService {
    private StudentDao studentDao;
    private Scanner scanner;    public StudentService(StudentDao studentDao, Scanner scanner) {
        this.studentDao = studentDao;
        this.scanner = scanner;
    }    // 添加学生
    public void addStudent() {
        System.out.print("输入学生资料进行添加: "); // name|age
        String info = scanner.nextLine();
        Student s = Student.buildStudent(info);
        if (studentDao.findStudent(s.getName()) != null) { throw new RuntimeException("此学生信息已经存在"); }
        studentDao.addStudent(s);
        System.out.println("\t添加成功\n");
    }    public void removeStudent() {
        System.out.print("输入学生姓名进行删除: ");
        String name = scanner.nextLine();
        Student s = studentDao.findStudent(name);        if (s == null) {
            System.out.println("\t查无此学生");
        } else {
            studentDao.removeStudent(s);
            System.out.println("\t已经删除学生: " + s);
        }
        System.out.println();
    }    // 查找学生
    public void findStudent() {
        System.out.print("输入学生姓名进行查询: ");
        String name = scanner.nextLine();
        Student s = studentDao.findStudent(name);
        if (s == null) {
            System.out.println("查无此学生");
        } else {
            System.out.println("\t搜索查找到的学生: " + s);
        }
        System.out.println();
    }    // 显示已经有的学生信息
    public void showStudents() {
        List<Student> students = studentDao.getStudents();        if (students.size() == 0) {
            System.out.println("列表中还没有任何学生");
        } else {
            System.out.println("========所有学生信息========");
        }        for (Student s : students) {
            System.out.println("\t" + s);
        }        System.out.println();
    }
}// 对学生数据进行执久化操作
class StudentDao {
    private List<Student> students;    public StudentDao() {
        students = new ArrayList<Student>();
    }    // 添加学生
    public void addStudent(Student student) {
        students.add(student);
    }    // 删除学生
    public void removeStudent(Student student) {
        students.remove(student);
    }    // 使用学生的名字查找进行查找
    public Student findStudent(String name) {
        for (Student s : students) {
            if (s.getName().equals(name)) { return s; }
        }        return null;
    }    // 返回学生列表的视图，不可修改
    public List<Student> getStudents() {
        return Collections.unmodifiableList(students);
    }
}class Student {
    private String name;
    private int age;    public Student() {
    }    public Student(String name, int age) {
        this.name = name;
        this.age = age;
    }    public String getName() {
        return name;
    }    public void setName(String name) {
        this.name = name;
    }    // Info format: name|age
    public static Student buildStudent(String studentInfo) {
        if (!studentInfo.matches("\\w+\\|\\d+")) { throw new RuntimeException(
            "The student information's format should be \"name|age\" without quote"); }        String[] infos = studentInfo.split("\\|");
        String name = infos[0].trim();
        int age = Integer.parseInt(infos[1]);        return new Student(name, age);
    }    @Override
    public String toString() {
        return String.format("Name:%s, Age:%d", name, age);
    }
}

*^_^*，这个学生管理系统我竟然还在写.
支持执久化，可以保存到文件，从文件读取
package test;import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.List;
import java.util.Scanner;
import java.util.Set;
import java.util.TreeSet;public class StudentManageSystem {
    /** StudentManager中提供的操作菜单 **/
    public static void showMenus() {
        String format = "              %s\n";
        System.out.println("----------------功能菜单------------------");
        System.out.printf(format, "0. 退出管理");
        System.out.printf(format, "1. 功能菜单");
        System.out.printf(format, "2. 显示学生");
        System.out.printf(format, "3. 查询学生");
        System.out.printf(format, "4. 添加学生");
        System.out.printf(format, "5. 删除学生");
        System.out.printf(format, "6. 修改学生");
        System.out.printf(format, "7. 读取学生");
        System.out.printf(format, "8. 保存学生");
        System.out.println("-------------------结束------------------");
        System.out.println();
    }    /** 管理学生信息 **/
    public void manageStudents() throws IOException {
        Scanner scanner = new Scanner(System.in);
        StudentDao sd = new StudentDao();
        StudentService ss = new StudentService(sd, scanner);        showMenus();
        int op = -1;        while (op != 0) {
            System.in.skip(System.in.available());
            System.out.print("输入菜单编号: ");
            op = scanner.nextInt();
            scanner.nextLine(); // 吃掉输入菜单编号后无效的回车字符            try {
                switch (op) {
                case 0:
                    break;
                case 1:
                    showMenus();
                    break;
                case 2:
                    ss.showStudents();
                    break;
                case 3:
                    ss.findStudents();
                    break;
                case 4:
                    ss.addStudent();
                    break;
                case 5:
                    ss.removeStudent();
                    break;
                case 6:
                    ss.updateStudent();
                    break;
                case 7:
                    ss.readStudents();
                    break;
                case 8:
                    ss.saveStudents();
                    break;
                default:
                    System.out.println("没有提供此项操作\n");
                }
            } catch (Exception e) {
                System.out.println("\t" + e.getMessage() + "\n");
            }
        }
    }    public static void main(String[] args) throws IOException {
        StudentManageSystem sm = new StudentManageSystem();
        sm.manageStudents();
        System.out.println("程序结束");
    }
}/** Service中的很多功能都是委托给Dao对象去完成 **/
class StudentService {
    private StudentDao studentDao;
    private Scanner scanner;    public StudentService(StudentDao studentDao, Scanner scanner) {
        this.studentDao = studentDao;
        this.scanner = scanner;
    }    // 添加学生
    public void addStudent() {
        System.out.print("输入学生资料进行添加，格式为id|name|age: "); // name|age
        String info = scanner.nextLine();
        Student s = Student.buildStudent(info);
        if (studentDao.hasStudent(s)) { throw new RuntimeException("此学生信息已经存在"); }
        studentDao.addStudent(s);
        System.out.println("\t添加成功\n");
    }    // 删除学生
    public void removeStudent() {
        System.out.print("输入学生id进行删除: ");
        int id = scanner.nextInt();
        Student s = studentDao.findStudent(id);        if (s == null) {
            System.out.println("\t查无此学生");
        } else {
            studentDao.removeStudent(s);
            System.out.println("\t已经删除学生: " + s);
        }
        System.out.println();
    }

    /** 修改学生信息 **/
    public void updateStudent() {
        System.out.print("修改学生信息，输入学生id: ");
        int id = scanner.nextInt();
        Student s = studentDao.findStudent(id);        if (s == null) {
            System.out.println("\t查无此学生");
        } else {
            scanner.nextLine(); // 吃掉回车
            System.out.println("\t学生: " + s);
            System.out.print("\t输入新的信息，格式为name|age: ");
            String line = scanner.nextLine().trim();
            if (!line.matches("\\w+\\|\\d+")) {
                throw new RuntimeException("输入的修改学生信息格式不对");
            }

            // 修改已搜索到的学生信息
            String[] infos = line.split("\\|");
            String name = infos[0];
            int age = Integer.parseInt(infos[1]);
            s.setName(name);
            s.setAge(age);
            System.out.println("\t修改完成");
        }
        System.out.println();
    }    /** 输入学生的学号或者姓名进行查找 **/
    public void findStudents() {
        System.out.print("输入学生ID或者姓名进行查询: ");
        String info = scanner.nextLine().trim();
        List<Student> ss = new ArrayList<Student>();        // 如果输入的是数字，默认为学号
        if (info.matches("\\d+")) {
            int id = Integer.parseInt(info);
            Student s = studentDao.findStudent(id);
            if (s != null) {
                ss.add(s);
            }
        } else {
            ss = studentDao.findStudents(info);
        }        // 输出查询结果
        if (ss.size() == 0) {
            System.out.println("查无此学生");
        } else {
            for (Student s : ss) {
                System.out.println("\t" + s);
            }
        }
        System.out.println();
    }    /** 显示已经有的学生信息 **/
    public void showStudents() {
        Set<Student> students = studentDao.getStudents();        if (students.size() == 0) {
            System.out.println("\t列表中还没有任何学生");
            return;
        }        System.out.println("========所有学生信息========");
        for (Student s : students) {
            System.out.println("\t" + s);
        }
        System.out.println();
    }    public void saveStudents() {
        studentDao.saveStudents();
        System.out.println("\t保存成功");
    }    public void readStudents() {
        studentDao.readStudents();
        System.out.println("\t读取完成");
    }
}

接上面
/** 对学生数据进行执久化操作 **/
class StudentDao {
    private Set<Student> students;
    private String fileName = "students.dat";    public StudentDao() {
        students = new TreeSet<Student>(new StudentComparator());
    }    /** 添加学生 **/
    public void addStudent(Student student) {
        students.add(student);
    }    /** 删除学生 **/
    public void removeStudent(Student student) {
        students.remove(student);
    }    /** 使用学生的id进行查找 **/
    public Student findStudent(int id) {
        for (Student s : students) {
            if (s.getId() == id) { return s; }
        }
        return null;
    }    /** 使用学生的名字查找进行查找 **/
    public List<Student> findStudents(String name) {
        List<Student> found = new ArrayList<Student>();
        for (Student s : students) {
            if (s.getName().equals(name)) {
                found.add(s);
            }
        }        return found;
    }    /** 判断学生是否已经存在 **/
    public boolean hasStudent(Student s) {
        return students.contains(s);
    }    /** 返回学生列表的视图，不可修改 **/
    public Set<Student> getStudents() {
        return Collections.unmodifiableSet(students);
    }    /** 把学生信息保存到文件 **/
    public void saveStudents() {
        ObjectOutputStream oos = null;
        try {
            oos = new ObjectOutputStream(new FileOutputStream(fileName));
            oos.writeObject(students);
        } catch (Exception e) {
            e.printStackTrace();
            throw new RuntimeException("保存失败");
        } finally {
            if (oos != null) {
                try {
                    oos.close();
                } catch (Exception e2) {
                }
            }
        }
    }    /** 从文件读取学生信息 **/
    public void readStudents() {
        ObjectInputStream ois = null;
        try {
            ois = new ObjectInputStream(new FileInputStream(fileName));
            students = (Set<Student>) ois.readObject();
        } catch (Exception e) {
            e.printStackTrace();
            throw new RuntimeException("读取失败");
        } finally {
            if (ois != null) {
                try {
                    ois.close();
                } catch (Exception e2) {
                }
            }
        }
    }
}/** 学生类，可以序列化保存到文件 **/
class Student implements Serializable {
    private static final long serialVersionUID = 1L;
    private int id;
    private int age;
    private String name;    public Student() {
    }    public Student(int id, String name, int age) {
        this.id = id;
        this.age = age;
        this.name = name;
    }    public String getName() {
        return name;
    }    public void setName(String name) {
        this.name = name;
    }    public int getId() {
        return id;
    }    public void setId(int id) {
        this.id = id;
    }    public int getAge() {
        return age;
    }    public void setAge(int age) {
        this.age = age;
    }    // Info format: id|name|age
    public static Student buildStudent(String studentInfo) {
        if (!studentInfo.matches("\\d+\\|\\w+\\|\\d+")) { throw new RuntimeException(
            "The student information's format should be \"id|name|age\" without quote"); }        String[] infos = studentInfo.split("\\|");
        int id = Integer.parseInt(infos[0]);
        String name = infos[1].trim();
        int age = Integer.parseInt(infos[2]);        return new Student(id, name, age);
    }    @Override
    public int hashCode() {
        return id;
    }    @Override
    public boolean equals(Object obj) {
        if (obj == null || obj.getClass() != this.getClass()) { return false; }
        Student other = (Student) obj;
        if (other.id == this.id) { return true; }
        return false;
    }    @Override
    public String toString() {
        return String.format("ID:%d, Name:%s, Age:%d", id, name, age);
    }
}// 使用TreeSet时需要的比较器
class StudentComparator implements Comparator<Student>, Serializable {
    private static final long serialVersionUID = 1L;    @Override
    public int compare(Student s1, Student s2) {
        return s1.getId() - s2.getId();
    }
}

这年头，发现csdn上面的都是求作业的，这是当代程序员的悲哀！

我有一个，不过是商业的。
money

package 基础;import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.List;
import java.util.Scanner;
import java.util.Set;
import java.util.TreeSet;public class StudentManageSystem { /** StudentManager中提供的操作菜单 * */ public static void showMenus() { String format = " %s\n"; System.out.println("----------------功能菜单------------------"); System.out.printf(format, "0. 退出管理"); System.out.printf(format, "1. 功能菜单"); System.out.printf(format, "2. 显示学生"); System.out.printf(format, "3. 查询学生"); System.out.printf(format, "4. 添加学生"); System.out.printf(format, "5. 删除学生"); System.out.printf(format, "6. 修改学生"); System.out.printf(format, "7. 读取学生"); System.out.printf(format, "8. 保存学生"); System.out.println("-------------------结束------------------"); System.out.println(); } /** 管理学生信息 * */ public void manageStudents() throws IOException { Scanner scanner = new Scanner(System.in); StudentDao sd = new StudentDao(); StudentService ss = new StudentService(sd, scanner); showMenus(); int op = -1; while (op != 0) { System.in.skip(System.in.available()); System.out.print("输入菜单编号: "); op = scanner.nextInt(); scanner.nextLine(); // 吃掉输入菜单编号后无效的回车字符 try { switch (op) { case 0: break; case 1: showMenus(); break; case 2: ss.showStudents(); break; case 3: ss.findStudents(); break; case 4: ss.addStudent(); break; case 5: ss.removeStudent(); break; case 6: ss.updateStudent(); break; case 7: ss.readStudents(); break; case 8: ss.saveStudents(); break; default: System.out.println("没有提供此项操作\n"); } } catch (Exception e) { System.out.println("\t" + e.getMessage() + "\n"); } } } public static void main(String[] args) throws IOException { StudentManageSystem sm = new StudentManageSystem(); sm.manageStudents(); System.out.println("程序结束"); }}/** Service中的很多功能都是委托给Dao对象去完成 * */class StudentService { private StudentDao studentDao; private Scanner scanner; public StudentService(StudentDao studentDao, Scanner scanner) { this.studentDao = studentDao; this.scanner = scanner; } // 添加学生 public void addStudent() { System.out.print("输入学生资料进行添加，格式为id|name|age: "); // name|age String info = scanner.nextLine(); Student s = Student.buildStudent(info); if (studentDao.hasStudent(s)) {
throw new RuntimeException("此学生信息已经存在");
} studentDao.addStudent(s); System.out.println("\t添加成功\n"); } // 删除学生 public void removeStudent() { System.out.print("输入学生id进行删除: "); int id = scanner.nextInt(); Student s = studentDao.findStudent(id); if (s == null) { System.out.println("\t查无此学生"); } else { studentDao.removeStudent(s); System.out.println("\t已经删除学生: " + s); } System.out.println(); } /** 修改学生信息 * */ public void updateStudent() { System.out.print("修改学生信息，输入学生id: "); int id = scanner.nextInt(); Student s = studentDao.findStudent(id); if (s == null) { System.out.println("\t查无此学生"); } else { scanner.nextLine(); // 吃掉回车 System.out.println("\t学生: " + s); System.out.print("\t输入新的信息，格式为name|age: "); String line = scanner.nextLine().trim(); if (!line.matches("\\w+\\|\\d+")) { throw new RuntimeException("输入的修改学生信息格式不对"); } // 修改已搜索到的学生信息 String[] infos = line.split("\\|"); String name = infos[0]; int age = Integer.parseInt(infos[1]); s.setName(name); s.setAge(age); System.out.println("\t修改完成"); } System.out.println(); } /** 输入学生的学号或者姓名进行查找 * */ public void findStudents() { System.out.print("输入学生ID或者姓名进行查询: "); String info = scanner.nextLine().trim(); List<Student> ss = new ArrayList<Student>(); // 如果输入的是数字，默认为学号 if (info.matches("\\d+")) { int id = Integer.parseInt(info); Student s = studentDao.findStudent(id); if (s != null) { ss.add(s); } } else { ss = studentDao.findStudents(info); } // 输出查询结果 if (ss.size() == 0) { System.out.println("查无此学生"); } else { for (Student s : ss) { System.out.println("\t" + s); } } System.out.println(); } /** 显示已经有的学生信息 * */ public void showStudents() { Set<Student> students = studentDao.getStudents(); if (students.size() == 0) { System.out.println("\t列表中还没有任何学生"); return; } System.out.println("========所有学生信息========"); for (Student s : students) { System.out.println("\t" + s); } System.out.println(); } public void saveStudents() { studentDao.saveStudents(); System.out.println("\t保存成功"); } public void readStudents() { studentDao.readStudents(); System.out.println("\t读取完成"); }}/** 对学生数据进行执久化操作 * */class StudentDao { private Set<Student> students; private String fileName = "students.dat"; public StudentDao() { students = new TreeSet<Student>(new StudentComparator()); } /** 添加学生 * */ public void addStudent(Student student) { students.add(student); } /** 删除学生 * */ public void removeStudent(Student student) { students.remove(student); } /** 使用学生的id进行查找 * */ public Student findStudent(int id) { for (Student s : students) { if (s.getId() == id) {
return s;
} } return null; } /** 使用学生的名字查找进行查找 * */ public List<Student> findStudents(String name) { List<Student> found = new ArrayList<Student>(); for (Student s : students) { if (s.getName().equals(name)) { found.add(s); } } return found; } /** 判断学生是否已经存在 * */ public boolean hasStudent(Student s) { return students.contains(s); } /** 返回学生列表的视图，不可修改 * */ public Set<Student> getStudents() { return Collections.unmodifiableSet(students); } /** 把学生信息保存到文件 * */ public void saveStudents() { ObjectOutputStream oos = null; try { oos = new ObjectOutputStream(new FileOutputStream(fileName)); oos.writeObject(students); } catch (Exception e) { e.printStackTrace(); throw new RuntimeException("保存失败"); } finally { if (oos != null) { try { oos.close(); } catch (Exception e2) { } } } } /** 从文件读取学生信息 * */ public void readStudents() { ObjectInputStream ois = null; try { ois = new ObjectInputStream(new FileInputStream(fileName)); Set<Student> readObject2 = (Set<Student>) ois.readObject();
Set<Student> readObject = readObject2;
students = readObject; } catch (Exception e) { e.printStackTrace(); throw new RuntimeException("读取失败"); } finally { if (ois != null) { try { ois.close(); } catch (Exception e2) { } } } }}/** 学生类，可以序列化保存到文件 * */class Student implements Serializable { private static final long serialVersionUID = 1L; private int id; private int age; private String name; public Student() { } public Student(int id, String name, int age) { this.id = id; this.age = age; this.name = name; } public String getName() { return name; } public void setName(String name) { this.name = name; } public int getId() { return id; } public void setId(int id) { this.id = id; } public int getAge() { return age; } public void setAge(int age) { this.age = age; } // Info format: id|name|age public static Student buildStudent(String studentInfo) { if (!studentInfo.matches("\\d+\\|\\w+\\|\\d+")) {
throw new RuntimeException( "The student information's format should be \"id|name|age\" without quote");
} String[] infos = studentInfo.split("\\|"); int id = Integer.parseInt(infos[0]); String name = infos[1].trim(); int age = Integer.parseInt(infos[2]); return new Student(id, name, age); } @Override
public int hashCode() { return id; } @Override
public boolean equals(Object obj) { if (obj == null || obj.getClass() != this.getClass()) {
return false;
} Student other = (Student) obj; if (other.id == this.id) {
return true;
} return false; } @Override
public String toString() { return String.format("ID:%d, Name:%s, Age:%d", id, name, age); }}// 使用TreeSet时需要的比较器class StudentComparator implements Comparator<Student>, Serializable { private static final long serialVersionUID = 1L; public int compare(Student s1, Student s2) {
return s1.getId() - s2.getId(); }}

我有一个关于c的……这个是以前学习C语言的时候最后的那个作业呢……可惜你要java的……

public static void showMainMenu() {
        System.out.println("*****************************");
        System.out.println("******欢迎进入学生管理系统******");
        System.out.println("*****************************");
        System.out.println("**         1.添加学生信息    **");
        System.out.println("**         2.删除学生信息    **");
        System.out.println("**         3.修改学生信息    **");
        System.out.println("**         4.查询学生信息    **");
        System.out.println("**         5.重登录         **");
        System.out.println("**         6.退出系统       **");
        System.out.println("*****************************");
        System.out.println("*****************************");
    }

这代码
多久没看到了这么多println了，怀念啊

调试易

谁给个学生信息管理系统java的

解决方案 »