• JAVAWEB选课系统


    按照网上的教程和素材制作,第一部分信息管理

    源码

    ackage com.ischoolbar.programmer.dao;
    
    import java.sql.ResultSet;
    import java.sql.SQLException;
    
    import com.ischoolbar.programmer.model.Admin;
    import com.ischoolbar.programmer.model.Clazz;
    
    /**
     * 
     * @author llq
     *管理员数据库操作封装
     */
    public class AdminDao extends BaseDao {
        
        public Admin login(String name ,String password){
            String sql = "select * from s_admin where name = '" + name + "' and password = '" + password + "'";
            ResultSet resultSet = query(sql);
            try {
                if(resultSet.next()){
                    Admin admin = new Admin();
                    admin.setId(resultSet.getInt("id"));
                    admin.setName(resultSet.getString("name"));
                    admin.setPassword(resultSet.getString("password"));
                    admin.setStatus(resultSet.getInt("status"));
                    return admin;
                }
            } catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            return null;
        }
        public boolean editPassword(Admin admin,String newPassword) {
            // TODO Auto-generated method stub
            String sql = "update s_admin set password = '"+newPassword+"' where id = " + admin.getId();
            return update(sql);
        }
    }
    package com.ischoolbar.programmer.dao;
    
    import java.sql.Connection;
    import java.sql.PreparedStatement;
    import java.sql.ResultSet;
    import java.sql.SQLException;
    import java.util.ArrayList;
    import java.util.List;
    
    import com.ischoolbar.programmer.util.DbUtil;
    
    /**
     * 
     * @author llq
     *基础dao,封装基本操作
     */
    public class BaseDao {
        private DbUtil dbUtil = new DbUtil();
        
        /**
         * 关闭数据库连接,释放资源
         */
        public void closeCon(){
            dbUtil.closeCon();
        }
        
        /**
         * 基础查询,多条查询
         */
        public ResultSet query(String sql){
            try {
                PreparedStatement prepareStatement = dbUtil.getConnection().prepareStatement(sql);
                return prepareStatement.executeQuery();
                
            } catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            return null;
        } 
        /**
         *改变数据库内容操作
         */
        public boolean update(String sql){
            try {
                return dbUtil.getConnection().prepareStatement(sql).executeUpdate() > 0;
            } catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            return false;
        }
        public Connection getConnection(){
            return dbUtil.getConnection();
        }
    }
    package com.ischoolbar.programmer.dao;
    
    import java.sql.Connection;
    import java.sql.PreparedStatement;
    import java.sql.ResultSet;
    import java.sql.SQLException;
    import java.util.ArrayList;
    import java.util.List;
    
    import com.ischoolbar.programmer.model.Admin;
    import com.ischoolbar.programmer.model.Clazz;
    import com.ischoolbar.programmer.model.Page;
    import com.ischoolbar.programmer.model.Student;
    import com.ischoolbar.programmer.util.StringUtil;
    
    public class StudentDao extends BaseDao {
        public boolean addStudent(Student student){
            String sql = "insert into s_student values(null,'"+student.getSn()+"','"+student.getName()+"'";
            sql += ",'" + student.getPassword() + "'," + student.getClazzId();
            sql += ",'" + student.getSex() + "','" + student.getMobile() + "'";
            sql += ",'" + student.getQq() + "',null)";
            return update(sql);
        }
        public boolean editStudent(Student student) {
            // TODO Auto-generated method stub
            String sql = "update s_student set name = '"+student.getName()+"'";
            sql += ",sex = '" + student.getSex() + "'";
            sql += ",mobile = '" + student.getMobile() + "'";
            sql += ",qq = '" + student.getQq() + "'";
            sql += ",clazz_id = " + student.getClazzId();
            sql += " where id = " + student.getId();
            return update(sql);
        }
        public boolean setStudentPhoto(Student student) {
            // TODO Auto-generated method stub
            String sql = "update s_student set photo = ? where id = ?";
            Connection connection = getConnection();
            try {
                PreparedStatement prepareStatement = connection.prepareStatement(sql);
                prepareStatement.setBinaryStream(1, student.getPhoto());
                prepareStatement.setInt(2, student.getId());
                return prepareStatement.executeUpdate() > 0;
            } catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            return update(sql);
        }
        public boolean deleteStudent(String ids) {
            // TODO Auto-generated method stub
            String sql = "delete from s_student where id in("+ids+")";
            return update(sql);
        }
        public Student getStudent(int id){
            String sql = "select * from s_student where id = " + id;
            Student student = null;
            ResultSet resultSet = query(sql);
            try {
                if(resultSet.next()){
                    student = new Student();
                    student.setId(resultSet.getInt("id"));
                    student.setClazzId(resultSet.getInt("clazz_id"));
                    student.setMobile(resultSet.getString("mobile"));
                    student.setName(resultSet.getString("name"));
                    student.setPassword(resultSet.getString("password"));
                    student.setPhoto(resultSet.getBinaryStream("photo"));
                    student.setQq(resultSet.getString("qq"));
                    student.setSex(resultSet.getString("sex"));
                    student.setSn(resultSet.getString("sn"));
                    return student;
                }
            } catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            return student;
        }
        public List<Student> getStudentList(Student student,Page page){
            List<Student> ret = new ArrayList<Student>();
            String sql = "select * from s_student ";
            if(!StringUtil.isEmpty(student.getName())){
                sql += "and name like '%" + student.getName() + "%'";
            }
            if(student.getClazzId() != 0){
                sql += " and clazz_id = " + student.getClazzId();
            }
            if(student.getId() != 0){
                sql += " and id = " + student.getId();
            }
            sql += " limit " + page.getStart() + "," + page.getPageSize();
            ResultSet resultSet = query(sql.replaceFirst("and", "where"));
            try {
                while(resultSet.next()){
                    Student s = new Student();
                    s.setId(resultSet.getInt("id"));
                    s.setClazzId(resultSet.getInt("clazz_id"));
                    s.setMobile(resultSet.getString("mobile"));
                    s.setName(resultSet.getString("name"));
                    s.setPassword(resultSet.getString("password"));
                    s.setPhoto(resultSet.getBinaryStream("photo"));
                    s.setQq(resultSet.getString("qq"));
                    s.setSex(resultSet.getString("sex"));
                    s.setSn(resultSet.getString("sn"));
                    ret.add(s);
                }
            } catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            return ret;
        }
        public int getStudentListTotal(Student student){
            int total = 0;
            String sql = "select count(*)as total from s_student ";
            if(!StringUtil.isEmpty(student.getName())){
                sql += "and name like '%" + student.getName() + "%'";
            }
            if(student.getClazzId() != 0){
                sql += " and clazz_id = " + student.getClazzId();
            }
            if(student.getId() != 0){
                sql += " and id = " + student.getId();
            }
            ResultSet resultSet = query(sql.replaceFirst("and", "where"));
            try {
                while(resultSet.next()){
                    total = resultSet.getInt("total");
                }
            } catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            return total;
        }
    package com.ischoolbar.programmer.util;
    
    import java.sql.Connection;
    import java.sql.Driver;
    import java.sql.DriverManager;
    import java.sql.SQLException;
    
    import javax.management.loading.PrivateClassLoader;
    /**
     * 
     * @author llq
     *数据库连util
     */
    public class DbUtil {
    
        private String dbUrl = "jdbc:mysql://localhost:3306/db_student_manager_web?useUnicode=true&characterEncoding=utf8";
        private String dbUser = "root";
        private String dbPassword = "";
        private String jdbcName = "com.mysql.jdbc.Driver";
        private Connection connection = null;
        public Connection getConnection(){
            try {
                Class.forName(jdbcName);
                connection = DriverManager.getConnection(dbUrl, dbUser, dbPassword);
                System.out.println("数据库链接成功!");
            } catch (Exception e) {
                // TODO Auto-generated catch block
                System.out.println("数据库链接失败!");
                e.printStackTrace();
            }
            return connection;
        }
        
        public void closeCon(){
            if(connection != null)
                try {
                    connection.close();
                    System.out.println("数据库链接已关闭!");
                } catch (SQLException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
        }
        
        public static void main(String[] args) {
            // TODO Auto-generated method stub
            DbUtil dbUtil = new DbUtil();
            dbUtil.getConnection();
        }
    
    }
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  • 原文地址:https://www.cnblogs.com/ICDTAD/p/12152648.html
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