JDBC初步学习

根据慕课网的课程JDBC之 “ 对岸的女孩看过来”进行学习。

MySQL安装及配置：

配置系统path环境变量：D:\Program Files\mysql-5.7.15-winx64\bin;

在主目录下新建my.ini配置文件，输入如下内容：

[mysql]
# 设置mysql客户端默认字符集
default-character-set=utf8
[mysqld]
#忽略root用户的密码
skip-grant-tables
#设置3306端口
port = 3306
# 设置mysql的安装目录
basedir=D:\Program Files\mysql-5.7.15-winx64
# 设置mysql数据库的数据的存放目录
datadir=D:\Program Files\mysql-5.7.15-winx64\data
# 允许最大连接数
max_connections=200
# 服务端使用的字符集默认为8比特编码的latin1字符集
character-set-server=utf8
# 创建新表时将使用的默认存储引擎
default-storage-engine=INNODB

安装mysql服务

管理员的身份运行cmd.exe，运行mysqld install命令，接着输入 net start mysql 启动服务，如果要停止服务，运行命令net stop mysql。

如果启动服务失败，且主目录下没有data目录，运行mysqld –initialize，然后启动服务。

进入mysql命令为mysql -u root -p，密码为空

首先将JDBC驱动程序mysql-connector-java-5.1.39-bin.jar文件添加到工程中。

MySQL相关的建表语句

create database imooc;

use imooc;

create table imooc_goddess(
id int primary key auto_increment,
user_name varchar(30) not null,
sex int,
age int,
birthday date,
email varchar(30),
mobile varchar(11),
create_user varchar(30),
create_date date,
update_user varchar(30),
update_date date,
isdel int
) default charset=utf8 auto_increment=1;

alter database imooc default character set 'utf8';
set character_set_client='utf8';
set character_set_connection='utf8';
set character_set_results='utf8';

Goddess.java

package com.imooc.model;

import java.util.Date;

public class Goddess {
private Integer id;
private String user_name;
private Integer sex=1;
private Integer age;
private Date birthday;
private String email;
private String mobile;
private String create_user;
private String update_user;
private Date create_date;
private Date update_date;
private Integer isdel=0;

//省略了各参数的getter和setter方法

@Override
public String toString() {
return "Goddess [id=" + id + ", user_name=" + user_name + ", sex=" + sex + ", age=" + age + ", birthday="
+ birthday + ", email=" + email + ", mobile=" + mobile + ", create_user=" + create_user
+ ", update_user=" + update_user + ", create_date=" + create_date + ", update_date=" + update_date
+ ", isdel=" + isdel + "]";
}

}

DBUtil.java

package com.imooc.db;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

public class DBUtil {

// 数据库地址，imooc为数据库名称
private static final String URL = "jdbc:mysql://127.0.0.1:3306/imooc";
// 用户名
private static final String NAME = "root";
// 密码
private static final String PASSWORD = "root";

private static Connection conn = null;

static {
try {
// 1.加载驱动程序
Class.forName("com.mysql.jdbc.Driver");
// 2.获得数据库的连接
conn = DriverManager.getConnection(URL, NAME, PASSWORD);
} catch (ClassNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}

public static Connection getConnection() {
return conn;
}

public static void main(String[] args) throws Exception {
// 1.加载驱动程序
Class.forName("com.mysql.jdbc.Driver");
// 2.获得数据库的连接
conn = DriverManager.getConnection(URL, NAME, PASSWORD);
// 3. 通过数据库的连接操作数据库，实现增删改查
Statement stmt = conn.createStatement();
ResultSet rs = stmt.executeQuery("select user_name,age from imooc_goddess");
while (rs.next()) {
System.out.println(rs.getString("user_name") + ":" + rs.getInt("age"));
}
}
}

GoddessDao.java

package com.imooc.dao;

import java.sql.Connection;
import java.sql.Date;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;

import com.imooc.db.DBUtil;
import com.imooc.model.Goddess;

/**
* 模型层
*
* */

public class GoddessDao {

public void addGoddess(Goddess g) throws Exception{
Connection conn=DBUtil.getConnection();
String sql=""+
"insert into imooc_goddess"+
"(user_name,sex,age,birthday,email,mobile,"+
"create_user,create_date,update_user,update_date,isdel)"+
"values("+
"?,?,?,?,?,?,?,current_date(),?,current_date(),?)";
PreparedStatement ptmt=conn.prepareStatement(sql);

ptmt.setString(1, g.getUser_name());
ptmt.setInt(2, g.getSex());
ptmt.setInt(3, g.getAge());
ptmt.setDate(4, new Date(g.getBirthday().getTime()));
ptmt.setString(5, g.getEmail());
ptmt.setString(6, g.getMobile());
ptmt.setString(7, g.getCreate_user());
ptmt.setString(8, g.getUpdate_user());
ptmt.setInt(9, g.getIsdel());

ptmt.execute();
}

public void updateGoddess(Goddess g) throws SQLException{
Connection conn=DBUtil.getConnection();
String sql=""+
" update imooc_goddess "+
" set user_name=?,sex=?,age=?,birthday=?,email=?,mobile=?, "+
" update_user=?,update_date=current_date(),isdel=? "+
" where id=? ";
PreparedStatement ptmt=conn.prepareStatement(sql);

ptmt.setString(1, g.getUser_name());
ptmt.setInt(2, g.getSex());
ptmt.setInt(3, g.getAge());
ptmt.setDate(4, new Date(g.getBirthday().getTime()));
ptmt.setString(5, g.getEmail());
ptmt.setString(6, g.getMobile());
ptmt.setString(7, g.getUpdate_user());
ptmt.setInt(8, g.getIsdel());
ptmt.setInt(9, g.getId());

ptmt.execute();
}
public void delGoddess(Integer id) throws SQLException{
Connection conn=DBUtil.getConnection();
String sql=""+
" delete from imooc_goddess "+
" where id=? ";
PreparedStatement ptmt=conn.prepareStatement(sql);

ptmt.setInt(1, id);

ptmt.execute();
}

/**
* 查询所有的基本信息
* */
public List<Goddess> query() throws Exception{
Connection conn=DBUtil.getConnection();
Statement stmt=conn.createStatement();
ResultSet rs=stmt.executeQuery("select id,user_name,age from imooc_goddess");

List<Goddess> gs=new ArrayList<Goddess>();
Goddess g=null;

while (rs.next()) {
g=new Goddess();
g.setId(rs.getInt("id"));
g.setUser_name(rs.getString("user_name"));
g.setAge(rs.getInt("age"));

gs.add(g);
}
return gs;
}

public List<Goddess> query(String name) throws Exception{
List<Goddess> result=new ArrayList<Goddess>();

Connection conn=DBUtil.getConnection();
StringBuilder sb=new StringBuilder();
sb.append("select * from imooc_goddess ");
sb.append(" where user_name=?");

PreparedStatement ptmt=conn.prepareStatement(sb.toString());
ptmt.setString(1, name);

ResultSet rs=ptmt.executeQuery();

Goddess g=null;
while (rs.next()) {
g=new Goddess();
g.setId(rs.getInt("id"));
g.setUser_name(rs.getString("user_name"));
g.setAge(rs.getInt("age"));
g.setSex(rs.getInt("sex"));
g.setBirthday(rs.getDate("birthday"));
g.setEmail(rs.getString("email"));
g.setMobile(rs.getString("mobile"));
g.setCreate_user(rs.getString("create_user"));
g.setCreate_date(rs.getDate("create_date"));
g.setUpdate_user(rs.getString("update_user"));
g.setUpdate_date(rs.getDate("update_date"));
g.setIsdel(rs.getInt("isdel"));

result.add(g);
}
return result;
}

/**
* 参数化查询方式
* 每个参数包含三部分
* name为参数名称
* rela为=或like等
* value为参数值
* */
public List<Goddess> query(List<Map<String, Object>> params) throws Exception{
List<Goddess> result=new ArrayList<Goddess>();

Connection conn=DBUtil.getConnection();
StringBuilder sb=new StringBuilder();
sb.append("select * from imooc_goddess where 1=1 ");

if (params!=null&¶ms.size()>0) {
for(int i=0;i<params.size();i++){
Map<String, Object> map=params.get(i);
sb.append(" and "+map.get("name")+" "+map.get("rela")+" "+map.get("value"));
}
}

PreparedStatement ptmt=conn.prepareStatement(sb.toString());
System.out.println(sb.toString());
ResultSet rs=ptmt.executeQuery();

Goddess g=null;
while (rs.next()) {
g=new Goddess();
g.setId(rs.getInt("id"));
g.setUser_name(rs.getString("user_name"));
g.setAge(rs.getInt("age"));
g.setSex(rs.getInt("sex"));
g.setBirthday(rs.getDate("birthday"));
g.setEmail(rs.getString("email"));
g.setMobile(rs.getString("mobile"));
g.setCreate_user(rs.getString("create_user"));
g.setCreate_date(rs.getDate("create_date"));
g.setUpdate_user(rs.getString("update_user"));
g.setUpdate_date(rs.getDate("update_date"));
g.setIsdel(rs.getInt("isdel"));

result.add(g);
}
return result;
}

public Goddess get(Integer id) throws SQLException{
Goddess g=null;
Connection conn=DBUtil.getConnection();
String sql=""+
" select * from imooc_goddess "+
" where id=? ";
PreparedStatement ptmt=conn.prepareStatement(sql);

ptmt.setInt(1, id);

ResultSet rs=ptmt.executeQuery();
while(rs.next()){
g=new Goddess();
g.setId(rs.getInt("id"));
g.setUser_name(rs.getString("user_name"));
g.setAge(rs.getInt("age"));
g.setSex(rs.getInt("sex"));
g.setBirthday(rs.getDate("birthday"));
g.setEmail(rs.getString("email"));
g.setMobile(rs.getString("mobile"));
g.setCreate_user(rs.getString("create_user"));
g.setCreate_date(rs.getDate("create_date"));
g.setUpdate_user(rs.getString("update_user"));
g.setUpdate_date(rs.getDate("update_date"));
g.setIsdel(rs.getInt("isdel"));
}
return g;
}
}

GoddessAction.java

package com.imooc.action;

import java.sql.SQLException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import com.imooc.dao.GoddessDao;
import com.imooc.model.Goddess;

/**
* 控制层
*
* */

public class GoddessAction {

public void add(Goddess goddess) throws Exception{
GoddessDao dao=new GoddessDao();
dao.addGoddess(goddess);
}

public void edit(Goddess goddess) throws SQLException{
GoddessDao dao=new GoddessDao();
dao.updateGoddess(goddess);
}

public void del(Integer id) throws SQLException{
GoddessDao dao=new GoddessDao();
dao.delGoddess(id);
}

public Goddess get(Integer id) throws SQLException{
GoddessDao dao=new GoddessDao();
return dao.get(id);
}

public List<Goddess> query() throws Exception{
GoddessDao dao=new GoddessDao();
return dao.query();
}

public List<Goddess> query(List<Map<String, Object>> params) throws Exception{
GoddessDao dao=new GoddessDao();
return dao.query(params);
}

public static void main(String[] args) throws Exception {
GoddessDao g=new GoddessDao();
List<Map<String, Object>> params=new ArrayList<Map<String,Object>>();

Map<String, Object> param=new HashMap<String, Object>();
param.put("name", "user_name");
param.put("rela", "like");
param.put("value", "'%小%'");
params.add(param);

List<Goddess> result=g.query(params);
for (Goddess goddess : result) {
System.out.println(goddess);
}

//      Goddess g1=new Goddess();
//      g1.setUser_name("小夏");
//      g1.setAge(23);
//      g1.setSex(1);
//      g1.setBirthday(new Date());
//      g1.setMobile("18756780000");
//      g1.setEmail("xiaoxia@imooc.com");
//      g1.setUpdate_user("ADMIN");
//      g1.setIsdel(1);
//      g1.setId(4);

//      g.delGoddess(3);
//      g.updateGoddess(g1);
//      g.addGoddess(g1);

//      List<Goddess> gs=g.query();
//      for(Goddess goddess:gs){
//          System.out.println(goddess);
//      }
//
//      Goddess sGoddess=g.get(1);
//      System.out.println(sGoddess);
}
}

View.java

package com.imooc.view;

import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.List;
import java.util.Scanner;

import com.imooc.action.GoddessAction;
import com.imooc.model.Goddess;

public class View {

private static final String CONTEXT="欢迎来到女神禁区：\n"
+ "下面是女神禁区的功能列表：\n"
+ "[MAIN/M]：主菜单\n"
+ "[QUERY/Q]：查看全部女神的信息\n"
+ "[GET/G]：查看某位女神的详细信息\n"
+ "[ADD/A]：添加女神信息\n"
+ "[UPDATE/U]：更新女神信息\n"
+ "[DELETE/D]：删除女神信息\n"
+ "[SEARCH/S]：查询女神信息（根据姓名、手机号来查询）\n"
+ "[EXIT/E]：退出女神禁区\n"
+ "[BREAK/B]：退出当前功能，返回主菜单";

private static final String OPERATION_MAIN="MAIN";
private static final String OPERATION_QUERY="QUERY";
private static final String OPERATION_GET="GET";
private static final String OPERATION_ADD="ADD";
private static final String OPERATION_UPDATE="UPDATE";
private static final String OPERATION_DELETE="DELETE";
private static final String OPERATION_SEARCH="SEARCH";
private static final String OPERATION_EXIT="EXIT";
private static final String OPERATION_BREAK="BREAK";

public static void main(String[] args) {
System.out.println(CONTEXT);
Scanner scan = new Scanner(System.in);

Goddess goddess=new Goddess();
GoddessAction action=new GoddessAction();
String previous=null;
Integer step=1;
while (scan.hasNext()) {
String in = scan.next().toString();
if (OPERATION_EXIT.equals(in.toUpperCase())
|| OPERATION_EXIT.substring(0, 1).equals(in.toUpperCase())) {
System.out.println("您已成功退出");
break;
} else if (OPERATION_QUERY.equals(in.toUpperCase())
|| OPERATION_QUERY.substring(0, 1).equals(in.toUpperCase())) {
try {
List<Goddess> list=action.query();
for (Goddess godd:list) {
System.out.println(godd.getId()+","+godd.getUser_name());
}
} catch (Exception e) {
e.printStackTrace();
}
} else if (OPERATION_ADD.equals(in.toUpperCase())
|| OPERATION_ADD.substring(0, 1).equals(in.toUpperCase())
|| OPERATION_ADD.equals(previous)) {
previous=OPERATION_ADD;

if(step==1){
System.out.println("请输入女神的[姓名]");
} else if (step==2){
goddess.setUser_name(in);
System.out.println("请输入女神的[年龄]");
} else if (step==3){
goddess.setAge(Integer.valueOf(in));
System.out.println("请输入女神的[生日]，格式如：yyyy-MM-dd");
} else if (step==4){
SimpleDateFormat sf=new SimpleDateFormat("yyyy-MM-dd");
Date birthday=null;
try {
birthday=sf.parse(in);
goddess.setBirthday(birthday);
System.out.println("请输入女神的[邮箱]");
} catch (ParseException e) {
// TODO Auto-generated catch block
e.printStackTrace();
System.out.println("您输入的格式有误，请重新输入");
step=3;
}
} else if (step==5){
goddess.setEmail(in);
System.out.println("请输入女神的[手机号]");
} else if (step==6){
goddess.setMobile(in);
try {
action.add(goddess);
System.out.println("新增女神成功");
} catch (Exception e) {
e.printStackTrace();
System.out.println("新增女神失败");
}
} if(OPERATION_ADD.equals(previous)){
step++;
}
} else {
System.out.println("您输入的值为：" + in);
}
}
}
}