1.什么是 JdbcTemplate

Spring 框架对 JDBC 进行封装，使用 JdbcTemplate 方便实现对数据库操作

2.导入需要的jar包

这是实现JdbcTemplate操作需要的jar包

3.编写代码

1.创建数据库

2.编写java代码

配置文件bean1.xml

<?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"
       xmlns:aop="http://www.springframework.org/schema/aop"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context https://www.springframework.org/schema/context/spring-context.xsd http://www.springframework.org/schema/aop https://www.springframework.org/schema/aop/spring-aop.xsd">
    <!--开启组件扫描-->
    <context:component-scan base-package="com.limi"></context:component-scan>

    <!-- 1.在 spring 配置文件配置数据库连接池-->
    <!-- 数据库连接池 -->
    <bean id="dataSource" class="com.alibaba.druid.pool.DruidDataSource" destroy-method="close">
        <property name="url" value="jdbc:mysql://localhost:3306/db_springtest" />
        <property name="username" value="root" />
        <property name="password" value="123456" />
        <property name="driverClassName" value="com.mysql.jdbc.Driver" />
    </bean>

    <!--2.配置 JdbcTemplate 对象，注入 DataSource-->
    <!-- JdbcTemplate 对象 -->
    <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
        <!--注入 dataSource-->
        <property name="dataSource" ref="dataSource"></property>
    </bean>

</beans>

BookService

package com.limi.service;

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

@Service
public class BookService {

    @Autowired
    private JdbcTemplate jdbcTemplate;

	//获取书的数量
    public int getBookCount(){
        String sql ="select count(*) from t_book";
        Integer count = jdbcTemplate.queryForObject(sql, Integer.class);
        return count;
    }
}

测试类MyTest

package com.limi.test;
import com.limi.service.BookService;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.springframework.jdbc.core.JdbcTemplate;

public class MyTest {

    @Test
    public void test1(){
        //1.加载bean的xml文件, 以src为根目录
        ApplicationContext context = new ClassPathXmlApplicationContext("bean1.xml");

        //2.获取配置的对象, 参数1:bean的id值, 参数2: 类名.class
        BookService bookService = context.getBean("bookService", BookService.class);

        //3.使用对象
        System.out.println("书的数量="+bookService.getBookCount());

    }
}

3.测试结果