我有一个带hibernate的java项目。它包含两个类：Student和Course。
现在我想为所有create, update and delete操作创建一个通用方法。
我上一次的学生管理代码是：
import org.hibernate.Session;
import org.hibernate.Transaction;
import java.io.Serializable;
import java.sql.SQLException;
import java.util.List;
public class ManageStudent extends Repository implements Serializable {
public static Student getStudent(Integer yourstcode) throws SQLException {
Session session = OpenSession1();
Student student = (Student) session.createQuery("from Student s where s.studentcode=:x").setParameter("x", yourstcode).uniqueResult();
session.close();
return student;
}
public static Student getStudentbyId(int stdNumber) throws SQLException {
Session session = OpenSession1();
Student student = (Student) session.createQuery("from Student s where s.id=:x").setParameter("x", stdNumber).uniqueResult();
session.close();
return student;
}
public static void addstudent(Student student) throws SQLException {
Session session = OpenSession1();
Transaction tx = session.beginTransaction();
session.saveOrUpdate(student);
tx.commit();
CloseSession(session);
}
public static void deletestudent(Student studentd) throws SQLException {
Session session = OpenSession1();
Transaction tx = session.beginTransaction();
session.delete(studentd);
tx.commit();
CloseSession(session);
}
public static List<Student> getAllStudents() throws SQLException {
Session session = OpenSession1();
List<Student> students = session.createQuery("from Student").list();
CloseSession(session);
return students;
}
public static void showStudents() throws SQLException {
for (Student student : getAllStudents()) {
System.out.println("StudentID: " + student.getId());
System.out.println("Student Code: " + student.getStudentcode());
System.out.println("FirstName: " + student.getFirstName());
System.out.println("LastName:" + student.getLastName());
System.out.println("FatherName: " + student.getFatherName());
System.out.println("Age: " + student.getAge());
System.out.println("Major: " + student.getMajor());
System.out.println("------------------------------------");
}
}
public static void updateStudent(Student student) throws SQLException {
Session session = OpenSession1();
Transaction tx = session.beginTransaction();
session.saveOrUpdate(student);
tx.commit();
CloseSession(session);
}
public static void showStudent(Student student) throws SQLException {
System.out.println(student.getFirstName());
System.out.println(student.getStudentcode());
System.out.println(student.getLastName());
System.out.printf("|%10s|%10s|%10s|%n", "NAME", "FAM", "AGE");
student.print();
}
}
现在我想写一个完成所有工作的通用方法：例如：用一个参数做更新学生，另一个用数据库添加学生，另一个删除学生。我读到了抽象，界面和通用，但我不明白我应该做什么......请帮助
这是我调用这些方法的情况。
import org.hibernate.SessionFactory;
import org.hibernate.cfg.Configuration;
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.util.Collection;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
public class Run {
static Integer coursecode;
static Integer yourstcode;
private static SessionFactory factory;
public static void main(String[] args) throws Exception {
BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
try {
// builder pattern (design pattern)
factory = new Configuration()
.configure()
.addAnnotatedClass(Student.class)
.addAnnotatedClass(Course.class)
.buildSessionFactory();
while (true) {
System.out.println("menu\n\n see student 1 \n see courses 2\n see your courses 3\n enter new student 4\n enter new course 5\n edit your profile 6\n delete a student 7\n delete a course 8\n choose course 9");
Integer i = Console.getInputInteger("\n\nplease select a number");
switch (i) {
case 1:
ManageStudent.showStudents();
break;
case 2:
ManageCourse.showCourse();
break;
case 3:
yourstcode = Console.getInputInteger("enter your code");
Collection<Course> course3= ManageCourse.getSelectedCourse(yourstcode);
ManageCourse.showCourseSelected(course3);
break;
case 4:
yourstcode = Console.getInputInteger("enter your code");
int stage = Console.getInputInteger("enter your age");
String stname = Console.getInputString("enter your name:");
String stlname = Console.getInputString("enter your lastname:");
String stfname = Console.getInputString("enter your fathername:");
String stmajor = Console.getInputString("enter your major:");
Student student = new Student();
student.setFirstName(stname);
student.setLastName(stlname);
student.setAge(stage);
student.setFatherName(stfname);
student.setMajor(stmajor);
student.setStudentcode(yourstcode);
ManageStudent.addstudent(student);
ManageStudent.showStudents();
break;
case 5:
coursecode = Console.getInputInteger("enter your code");
String coursename1 = Console.getInputString("enter name of lesson:");
int coursegrade1 = Console.getInputInteger("enter grade");
Course course1 = new Course();
course1.setCoursecode(coursecode);
course1.setCoursename(coursename1);
course1.setGrade(coursegrade1);
ManageCourse.addCourse(course1);
ManageCourse.showCourse();
break;
case 6:
yourstcode = Console.getInputInteger("enter your code");
Student student2 = ManageStudent.getStudent(yourstcode);
ManageStudent.showStudent(student2);
System.out.println("-----------edit your profile-----------");
student2.setId(student2.getId());
student2.setStudentcode(Console.getInputInteger("enter your age"));
student2.setFirstName(Console.getInputString("enter your name:"));
student2.setLastName(Console.getInputString("enter your lastname:"));
student2.setFatherName(Console.getInputString("enter your fathername:"));
student2.setMajor(Console.getInputString("enter your major:"));
ManageStudent.updateStudent(student2);
ManageStudent.showStudents();
break;
case 7:
yourstcode = Console.getInputInteger("enter your code");
Student studentd = ManageStudent.getStudent(yourstcode);
ManageStudent.deletestudent(studentd);
ManageStudent.showStudents();
break;
case 8:
coursecode = Console.getInputInteger("enter your code");
Course coursed = ManageCourse.getCourse(coursecode);
ManageCourse.deleteCourse(coursed);
ManageCourse.showCourse();
break;
case 9:
List<Student> students = ManageStudent.getAllStudents();
List<Course> courses = ManageCourse.getAllCourse();
Set<Course> courseList = new HashSet<>();
for (Student student1 : students) {
System.out.print(student1.getStudentcode());
System.out.println("StudentID: " + student1.getId());
System.out.println("StudentCode: " + student1.getStudentcode());
System.out.println("FirstName: " + student1.getFirstName());
System.out.println("LastName:" + student1.getLastName());
System.out.println("FatherName: " + student1.getFatherName());
System.out.println("Age: " + student1.getAge());
System.out.println("Major: " + student1.getMajor());
System.out.println("------------------------------------");
}
System.out.println("Enter studentid: ");
int stdNumber = Console.getInputInteger("enter your code");
Student student1 = ManageStudent.getStudentbyId(stdNumber);
System.out.print("Courseid");
System.out.print(" coursename");
System.out.println(" grade");
for (Course course : courses) {
System.out.print(course.getId());
System.out.print(" " + course.getCoursename());
System.out.println(" " + course.getGrade());
}
System.out.println("Enter Number of Course Selection: ");
int numCourseSelection = Integer.parseInt(reader.readLine());
if (numCourseSelection != 0) {
for (int j = 1; j <= numCourseSelection; j++) {
System.out.println("Enter Course id" + j + ": ");
Course course = ManageCourse.getCourse( Integer.parseInt(reader.readLine()));
courseList.add(course);
}
student1.setCourses(courseList);
}
ManageCourse.Courseselection(student1);
}
}
} catch (Throwable ex) {
System.err.println("Failed to create sessionFactory object." + ex);
throw new ExceptionInInitializerError(ex);
}
}
}