A卷

sql


create table stu
(
   sid int  not null primary key,
   sname varchar(20),
   spsw varchar(20)
);

insert into stu values(1,'A1','123');
insert into stu values(2,'A2','123');
insert into stu values(3,'A3','123');
insert into stu values(4,'A4','123');
insert into stu values(5,'A5','123');

-- code --

StuDAO
package com.xiaohu.dao;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.util.ArrayList;
import java.util.List;

import com.xiaohu.entity.StuEntity;
import com.xiaohu.utils.DBConn;

public class StuDAO {
    private DBConn db = new DBConn();
    private Connection conn = null;
    private PreparedStatement pre = null;
    private ResultSet rs = null;

//    增
    public void addStu(StuEntity stu) {
        conn = db.GetConn();
        String sql = "insert into stu values(?,?,?)";
        try {
            pre=conn.prepareStatement(sql);
            pre.setInt(1, stu.getSid());
            pre.setString(2, stu.getSname());
            pre.setString(3, stu.getSpsw());
            pre.executeUpdate();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
//    删
    public void delStu(int sid) {
        conn = db.GetConn();
        String sql = "delete  from stu where sid=?";
        try {
            pre=conn.prepareStatement(sql);
            pre.setInt(1, sid);
            pre.executeUpdate();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
//    改
    public void updateStu(int sid,StuEntity stu) {
        conn = db.GetConn();
        String sql = "update stu set sname=?,spsw=? where sid=?";
        try {
            pre = conn.prepareStatement(sql);
            pre.setString(1, stu.getSname());
            pre.setString(2, stu.getSpsw());
            pre.setInt(3, sid);
            pre.executeUpdate();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
//    查
    public List<StuEntity> getAll(){
        conn=db.GetConn();
        String sql="select * from stu";
        List<StuEntity> list = new ArrayList<StuEntity>();
        try {
            pre=conn.prepareStatement(sql);
            rs = pre.executeQuery();
            while(rs.next()) {
                StuEntity stu = new StuEntity();
                stu.setSid(rs.getInt("sid"));
                stu.setSname(rs.getString("sname"));
                stu.setSpsw(rs.getString("spsw"));
                list.add(stu);
            }

        } catch (Exception e) {
            e.printStackTrace();
        }
        return list;
    }
//    查询一个
    public StuEntity getOne(int sid) {
        conn = db.GetConn();
        StuEntity stu = new StuEntity();
        String sql = "select * from stu where sid = ?";
        try {
            pre = conn.prepareStatement(sql);
            pre.setInt(1, sid);
            rs = pre.executeQuery();
            while(rs.next()) {
                stu.setSid(rs.getInt("sid"));
                stu.setSname(rs.getString("sname"));
                stu.setSpsw(rs.getString("spsw"));
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        return stu;
    }
}
StuEntity
package com.xiaohu.entity;

public class StuEntity {
    private int sid;
    private String sname;
    private String spsw;
    public int getSid() {
        return sid;
    }
    public void setSid(int sid) {
        this.sid = sid;
    }
    public String getSname() {
        return sname;
    }
    public void setSname(String sname) {
        this.sname = sname;
    }
    public String getSpsw() {
        return spsw;
    }
    public void setSpsw(String spsw) {
        this.spsw = spsw;
    }
    
}
DBConn
package com.xiaohu.utils;

import java.sql.Connection;
import java.sql.DriverManager;

public class DBConn {
    public Connection GetConn() {
        Connection conn = null;
        try {
            String Driver = "com.mysql.cj.jdbc.Driver";
            String url = "jdbc:mysql://localhost:3306/test";
            String user = "root";
            String password = "root";
            Class.forName(Driver);
            conn = DriverManager.getConnection(url,user,password);
        } catch (Exception e) {
            e.printStackTrace();
        }
        return conn;
    }
}
Test
package com.xiaohu.test;

import java.util.List;

import com.xiaohu.dao.StuDAO;
import com.xiaohu.entity.StuEntity;
import com.xiaohu.utils.DBConn;

public class Test1 {

    public static void main(String[] args) {
//        增
        StuDAO stu = new StuDAO();
        StuEntity stuEntity = new StuEntity();
        stuEntity.setSid(1001);
        stuEntity.setSname("xiaoming");
        stuEntity.setSpsw("123456");
        stu.addStu(stuEntity);
        
//        改
        StuEntity stuEntity1 = new StuEntity();
        stuEntity1.setSid(1001);
        stuEntity1.setSname("11xiaoming11");
        stuEntity1.setSpsw("12345611");
        stu.updateStu(1001, stuEntity1);
        
//        查一个
        StuEntity stu1 = stu.getOne(1001);
        System.out.println(stu1.getSid()+"\t"+stu1.getSname());
        
//        删
        stu.delStu(1001);
        
//        查
        List<StuEntity> list =     stu.getAll();
        for(int i=0;i<list.size();i++) {
            System.out.println(list.get(i).getSname());
        }
        
    }
}

B卷

sql

CREATE TABLE dept(
    pid int PRIMARY KEY COMMENT '部门编号',
    pname varchar(50) COMMENT '部门名称',
    premark varchar(100) COMMENT '备注说明'
);

CREATE TABLE emp(
    eid int PRIMARY KEY COMMENT '员工编号',
    pid int COMMENT '部门编号',
    ename VARCHAR(50) COMMENT '员工姓名',
    epsw VARCHAR(100) COMMENT '员工密码',
    FOREIGN KEY (pid) REFERENCES dept(pid)
);

INSERT INTO dept VALUES(1001,'设计部','暂无'),
                                          (1002,' 产品部','暂无'),
                                            (1003,'运营部','暂无'),
                                            (1004,'开发部','暂无');
INSERT INTO emp VALUES (101,1001,'小王','123456'),
                                                (102,1002,'小李','123456'),    
                                                (103,1003,'小张','123456'),        
                                                (104,1004,'小开','123456');
                                                
SELECT * FROM dept;
SELECT * FROM emp WHERE eid=101;                                                

-code-

DeptDAO
package org.xiaohu.dao;

import org.xiaohu.entity.DeptEntity;
import org.xiaohu.utils.DBConn;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.util.ArrayList;
import java.util.List;

public class DeptDAO {
    private Connection conn = null;
    private DBConn db;
    public DeptDAO(){
        db  = new DBConn();
    }
//  部门添加
    public void add(DeptEntity dept){
        conn = db.DBConnection();
        String sql = "INSERT INTO dept VALUES(?,?,?)";
        try
        {
            PreparedStatement pre = conn.prepareStatement(sql);
            pre.setInt(1, dept.getPid());
            pre.setString(2, dept.getPname());
            pre.setString(3, dept.getPremark());
            pre.executeUpdate();
            System.out.println("添加成功");
        }
        catch(Exception e)
        {
            e.printStackTrace();
        }
    }
//    部门全查询
    public List<DeptEntity> getAllDeptInfo()
    {
        List<DeptEntity> list = new ArrayList<DeptEntity>();


        conn = db.DBConnection();
        String sql = "SELECT * FROM dept";
        try
        {
            PreparedStatement pre = conn.prepareStatement(sql);
            ResultSet rs = pre.executeQuery();
            while(rs.next())
            {
                DeptEntity dept = new DeptEntity();
                dept.setPid(rs.getInt("pid"));
                dept.setPname(rs.getString("pname"));
                dept.setPremark(rs.getString("premark"));
                list.add(dept);
            }
        }
        catch(Exception e)
        {
            e.printStackTrace();
        }
        return list;
    }
}
EmpDAO
package org.xiaohu.dao;

import org.xiaohu.entity.EmpEntity;
import org.xiaohu.utils.DBConn;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;

public class EmpDAO {
    private Connection conn = null;
    private DBConn db;
    public EmpDAO()
    {
        db = new DBConn();
    }
    //   查询某个员工
    public EmpEntity getOneEmpInfo(int eid){
        conn = db.DBConnection();//连接数据库
        EmpEntity emp = new EmpEntity();
        String sql = "SELECT * FROM emp WHERE eid=?";
        try
        {
            PreparedStatement pre = conn.prepareStatement(sql);
            pre.setInt(1, eid);
            ResultSet rs = pre.executeQuery();
            while(rs.next())
            {
                emp.setEid(rs.getInt("eid"));
                emp.setEname(rs.getString("ename"));
                emp.setEpsw(rs.getString("epsw"));
                emp.setPid(rs.getInt("pid"));
            }
        }
        catch(Exception e)
        {
            e.printStackTrace();
        }
        return  emp;
    }
}
DBConn
package org.xiaohu.utils;

import java.sql.Connection;
import java.sql.DriverManager;

//数据库连接工具类
public class DBConn {
    private static final String DRIVER = "com.mysql.cj.jdbc.Driver";
    private static final String URL = "jdbc:mysql://localhost:3306/xiaohu";
    private static final String USER = "root";
    private static final String PASSWORD = "root";
    public Connection DBConnection()
    {
        Connection conn = null;
        try
        {
            Class.forName(DRIVER);
            conn = DriverManager.getConnection(URL, USER, PASSWORD);
        }
        catch (Exception e)
        {
            e.printStackTrace();
        }finally {
            if(conn == null){
                System.out.println("数据库连接失败");
            }
            else {
                System.out.println("数据库连接成功");
            }
        }
        return conn;
    }
}
DeptEntity
package org.xiaohu.entity;

public class DeptEntity {
    private int pid;
    private String pname;
    private String premark;

    public int getPid() {
        return pid;
    }

    public void setPid(int pid) {
        this.pid = pid;
    }

    public String getPname() {
        return pname;
    }

    public void setPname(String pname) {
        this.pname = pname;
    }

    public String getPremark() {
        return premark;
    }

    public void setPremark(String premark) {
        this.premark = premark;
    }
}
EmpEntity
package org.xiaohu.entity;

public class EmpEntity {
    private int eid;
    private int pid;
    private String ename;
    private String epsw;

    public int getEid() {
        return eid;
    }

    public void setEid(int eid) {
        this.eid = eid;
    }

    public int getPid() {
        return pid;
    }

    public void setPid(int pid) {
        this.pid = pid;
    }

    public String getEname() {
        return ename;
    }

    public void setEname(String ename) {
        this.ename = ename;
    }

    public String getEpsw() {
        return epsw;
    }

    public void setEpsw(String epsw) {
        this.epsw = epsw;
    }
}
DeptTest
package org.xiaohu.test;

import org.xiaohu.dao.DeptDAO;
import org.xiaohu.entity.DeptEntity;

import java.util.List;

public class DeptTest {
    public static void main(String[] args) {
        DeptEntity dept = new DeptEntity();
        DeptDAO deptDAO = new DeptDAO();
//        dept.setPid(1005);
//        dept.setPname("测试部");
//        dept.setPremark("测试部");
//        deptDAO.add(dept);

        System.out.println("部门编号\t部门名称\t备注说明");
        List<DeptEntity> list  = deptDAO.getAllDeptInfo();
        for(int i = 0;i<list.size();i++){
            System.out.println(list.get(i).getPid()+'\t'+list.get(i).getPname()+'\t'+list.get(i).getPremark());
        }
    }
}
EmpTest
package org.xiaohu.test;

import org.xiaohu.dao.EmpDAO;
import org.xiaohu.entity.EmpEntity;

public class EmpTest {
    public static void main(String[] args) {
        EmpDAO empDAO = new EmpDAO();
        EmpEntity emp = empDAO.getOneEmpInfo(101);
        System.out.println(emp.getEid()+ emp.getPid()+emp.getEname());
    }
}
最后修改:2024 年 12 月 16 日
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