Java 學生管理系統 使用JavaBean分層

客戶端操作（主函數）Tset.java

package com.edu.test;

import java.sql.SQLException;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.Scanner;

import com.edu.dao.StuDao;
import com.edu.javabean.Student;

public class Test {

	public static void showMenu(){
		System.out.println("請選擇序號：");
		System.out.println("1.增加，2.更新，3.刪除，4.查詢，5.退出");
	}
	public static void main(String[] args) throws SQLException {
		Scanner scan=new Scanner(System.in);
		showMenu();
		int i=0;
		StuDao dao=new StuDao();
		while((i=scan.nextInt())!=5){
			switch(i)
			{
			case 1:
				//增加
				System.out.println("請輸入學生姓名：");
				String name=scan.next();
				System.out.println("請輸入學生性別：");
				String sex=scan.next();
				System.out.println("請輸入學生的年齡：");
				int age=scan.nextInt();
				System.out.println("請輸入學生的成績:");
				int score=scan.nextInt();
				
				Student student =new Student();
				student.setName(name);
				student.setSex(sex);
				student.setAge(age);
				student.setScore(score);
				boolean res = dao.insertStu(student);
				if(res)
					System.out.println("錄入學生信息成功");
				
				showMenu();
				break;
			case 2:
				//更新
				System.out.println("請輸入要更改的學生編號：");
				int id=scan.nextInt();
				System.out.println("請輸入學生新的姓名：");
				name=scan.next();
				System.out.println("請輸入學生新的性別：");
				sex=scan.next();
				System.out.println("請輸入學生的新的年齡：");
				age=scan.nextInt();
				System.out.println("請輸入學生的新的成績:");
				score=scan.nextInt();
				
				Student student2 =new Student();
				student2.setName(name);
				student2.setSex(sex);
				student2.setAge(age);
				student2.setScore(score);
				student2.setId(id);
				
				boolean res2 = dao.updateStu(student2);
				if(res2)
					System.out.println("更新學生信息成功");
				showMenu();
				break;
			case 3:
				//刪除
				System.out.println("請輸入要刪除的學生編號：");
				int id2=scan.nextInt();
				boolean res3 = dao.deleteStu(id2);
				if(res3)
					System.out.println("刪除學生信息成功");
				showMenu();
				break;
			case 4:
				//查詢
				ArrayList list=dao.getAllStus();
				Iterator it= list.iterator();
				System.out.println("id\tname\tsex\tage\tscore\t");
				while(it.hasNext()){
					Student student3=(Student) it.next();
					System.out.println(student3.getId()+"\t"+student3.getName()+
							"\t"+student3.getSex()+"\t"+student3.getAge()+
							"\t"+student3.getScore()+"\t");
					
				}
				showMenu();
				break;
			default:
				showMenu();
				break;
				
			}
		}
		System.out.println("謝謝使用，歡迎下次使用");
	}

}

學生類Student.java

package com.edu.javabean;

//學生類

public class Student {
	private int id;
	private String name;
	private String sex;
	private int age;
	private int score;

	public Student() {

	}

	public Student(int id, String name, String sex, int age, int score) {
		this.id = id;
		this.name = name;
		this.sex = sex;
		this.age = age;
		this.score = score;
	}

	public int getId() {
		return id;
	}

	public void setId(int id) {
		this.id = id;
	}

	public String getName() {
		return name;
	}

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

	public String getSex() {
		return sex;
	}

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

	public int getAge() {
		return age;
	}

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

	public int getScore() {
		return score;
	}

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

}

中間連接類StuDao.java

package com.edu.dao;

import java.sql.*;
import java.util.ArrayList;

import com.edu.javabean.Student;
import com.edu.util.ConnectionFactory;

//中間過渡層，連接主函數操作與數據庫操作


//查詢表
public class StuDao {
	public ArrayList getAllStus() throws SQLException{
		ArrayList list=new ArrayList();
		Connection conn=ConnectionFactory.getConnection();
		String sql="select * from student";
		PreparedStatement pstmt=conn.prepareStatement(sql);
		ResultSet rs = pstmt.executeQuery();
		Student stu=null;
		while(rs.next()){
			stu = new Student(rs.getInt(1), rs.getString(2), rs.getString(3),
					rs.getInt(4), rs.getInt(5));
			list.add(stu);
		}
		rs.close();
		pstmt.close();
		conn.close();
		return list;
	}
	
	//插入表
	public boolean insertStu(Student student) throws SQLException{
		Connection conn=ConnectionFactory.getConnection();
		String sql="insert into student(name,sex,age,score) values(?,?,?,?)";
		PreparedStatement pstmt=conn.prepareStatement(sql);
		pstmt.setString(1, student.getName());
		pstmt.setString(2, student.getSex());
		pstmt.setInt(3, student.getAge());
		pstmt.setInt(4, student.getScore());
		
		int res = pstmt.executeUpdate();

		pstmt.close();
		conn.close();
		
		if(res>0)
			return true;
		else
			return false;
	}
	
	//更新表
	public boolean updateStu(Student student) throws SQLException{
		Connection conn=ConnectionFactory.getConnection();
		String sql="update student set name=?,sex=?,age=?,score=? where id=?";
		PreparedStatement pstmt=conn.prepareStatement(sql);
		pstmt.setString(1, student.getName());
		pstmt.setString(2, student.getSex());
		pstmt.setInt(3, student.getAge());
		pstmt.setInt(4, student.getScore());
		pstmt.setInt(5, student.getId());
		
		int res = pstmt.executeUpdate();

		pstmt.close();
		conn.close();
		
		if(res>0)
			return true;
		else
			return false;
	}
	
	//刪除行
	public boolean deleteStu(int id) throws SQLException{
		Connection conn=ConnectionFactory.getConnection();
		String sql="delete from student where id=?";
		PreparedStatement pstmt=conn.prepareStatement(sql);
		
		pstmt.setInt(1, id);
		
		int res = pstmt.executeUpdate();

		pstmt.close();
		conn.close();
		
		if(res>0)
			return true;
		else
			return false;
	}
	
	
}

底層數據庫操作類ConnectionFactory.java

package com.edu.util;

import java.sql.*;

//直接操作數據庫

public class ConnectionFactory {
	private static ConnectionFactory ref = new ConnectionFactory();

	private ConnectionFactory() {
		try {
			Class.forName("com.mysql.jdbc.Driver");
		} catch (ClassNotFoundException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}

	}
	
	public static Connection getConnection() throws SQLException{
		String url="jdbc:mysql:///test?useSSL=true";
		return DriverManager.getConnection(url, "root", "root");
	}
	
	public static void close(ResultSet rs){
		try {
			rs.close();
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}
	
	public static void close(PreparedStatement pstmt){
		try {
			pstmt.close();
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}
	
	public static void close(Connection conn){
		try {
			conn.close();
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}
}

將數據庫操作ConnectionFactory與前端操作mian函數分隔開，使其分層，使用中間層StuDao訪問，降低數據庫訪問壓力，提高數據庫安全性