1. 什么是JdbcTemplate

   1. Spring对JDBC进行了封装——JDBC模板，通过它实现对数据库的增删改操作。

2. 准备工作

   1. 引入jar包：（1）mysql依赖：在哪下载Mysql数据库的JDBC驱动jar包__清风明月的博客-CSDN博客_mysql驱动jar包在哪（2）德鲁伊druid连接池：Central Repository: com/alibaba/druid（3）spring jdbc（4）spring tx（事务）(5)spring orm(整合Mybatis操作数据库需要)
   2. 在Spring配置文件中配置数据库的连接池。

          <!--数据库连接池-->
          <bean id="dataSource" class="com.alibaba.druid.pool.DruidDataSource"
                destroy-method="close">
              <property name="driverClassName" value="com.mysql.jdbc.Driver"/>
              <property name="url" value="jdbc:mysql:///myemployees"/>
              <property name="username" value="root"/>
              <property name="password" value="950728"/>
          </bean>

                 3.配置JdbcTemplate对象，注入Datasource 

    <!--配置JdbcTemplate-->
    <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
        <!--JdbcTemplate对象中注入DataSource，源码中是使用setDataSource()方法-->
        <property name="dataSource" ref="dataSource"></property>
    </bean>

                4.创建一个Service类和Dao类，在Service里面注入Dao，在Dao中注入Jdbc Template对象

在xml配置中开启组件扫描

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
                           http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd">
    <!--开启组件扫描-->
    <context:component-scan base-package="com.company"></context:component-scan>

在Service里面注入dao

package com.company.service;

import com.company.dao.BookDao;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

@Service
public class BookService {
    //在Service里面注入dao
    @Autowired
    private BookDao bookDao;
}

 在dao里面注入jdbc template

package com.company.dao;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.stereotype.Repository;

@Repository
public class BookDaoImpl implements BookDao {
    //dao里面注入JdbcTemplate
    @Autowired
    private JdbcTemplate jdbctemplate;
}

3.JdbcTemplate操作数据库

1.  对应数据库表先创建出实体类User类

   package com.company.entity;
   
   public class User {
       private String userId;
       private String userName;
       private String userEmail;
       //get set方法
   
       public String getUserId() {
           return userId;
       }
       public String getUserName() {
           return userName;
       }
       public String getUserEmail() {
           return userEmail;
       }
   
       public void setUserId(String userId) {
           this.userId = userId;
       }
       public void setUserName(String userName) {
           this.userName = userName;
       }
       public void setUserEmail(String userEmail) {
           this.userEmail = userEmail;
       }
   }