07- JdbcTemplate

10- JdbcTemplate

10.1 JdbcTemplate概述

#JdbcTemplate是spring提供的一个模板类，它是对jdbc的封装。用于支持持久层的操作。它的特点是：简单、方便

10.2 入门案例

10.2.1 SQL数据表结构

-- 创建账户表
create table account(
	id int primary key auto_increment,
	name varchar(40),
	money float
)ENGINE=InnoDB character set utf8 collate utf8_general_ci;

-- 初始化新增三个账户
insert into account(name,money) values('kebe',1000);
insert into account(name,money) values('curry',1500);
insert into account(name,money) values('james',2000);

select * from account;

10.2.2 项目目录

10.2.3 pom.xml

<!--依赖版本-->
<properties>
    <!-- spring版本 -->
    <spring.version>5.0.2.RELEASE</spring.version>
</properties>

<!--spring jdbc依赖-->
<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-jdbc</artifactId>
    <version>${spring.version}</version>
    <!--lombok插件-->
    <dependency>
        <groupId>org.projectlombok</groupId>
        <artifactId>lombok</artifactId>
        <version>1.18.16</version>
    </dependency>
</dependency>

10.2.4 案例代码

package cn.guardwhy.jdbc;

import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.datasource.DriverManagerDataSource;

/**
 * spring JdbcTemplate入门案例
 */
public class JdbcTemplateDemo {
    
    
    public static void main(String[] args) {
    
    
        // 1.创建JdbcTemplate对象
        JdbcTemplate jdbcTemplate = new JdbcTemplate();
        // 2.设置数据源对象
        DriverManagerDataSource dataSource = new DriverManagerDataSource();
        dataSource.setDriverClassName("com.mysql.jdbc.Driver");
        dataSource.setUrl("jdbc:mysql://127.0.0.1:3306/spring");
        dataSource.setUsername("root");
        dataSource.setPassword("root");

        jdbcTemplate.setDataSource(dataSource);
        // 3.添加账户信息
        jdbcTemplate.update("insert into account(name,money) values('Duncan',2500)");
    }
}

10.3 IOC管理JdbcTemplate

10.3.1 bean.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"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
       http://www.springframework.org/schema/beans/spring-beans.xsd">

    <!--配置JdbcTemplate-->
    <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
        <!--注入数据源对象-->
        <property name="dataSource" ref="dataSource"></property>
    </bean>

    <!--配置数据源对象-->
    <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
        <!--注入连接数据库-->
        <property name="driverClassName" value="com.mysql.jdbc.Driver"></property>
        <property name="url" value="jdbc:mysql://127.0.0.1:3306/spring"></property>
        <property name="username" value="root"></property>
        <property name="password" value="root"></property>
    </bean>
</beans>

10.3.2 案例代码

package cn.guardwhy.jdbc;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.springframework.jdbc.core.JdbcTemplate;

/**
 * spring JdbcTemplate入门案例
 */
public class JdbcTemplateDemo {
    
    
    public static void main(String[] args) {
    
    
        // 1.加载spring配置文件,创建spring IOC容器
        ApplicationContext context = new ClassPathXmlApplicationContext("classpath:bean.xml");
        // 2.从spring IOC容器中,获取JdbcTemplate
        JdbcTemplate jdbcTemplate = (JdbcTemplate) context.getBean("jdbcTemplate");
        // 3.添加账户信息
        jdbcTemplate.update("insert into account(name,money) values('Gasol',3500)");
    }
}

10.4 实现完整CRUD操作

10.4.1 项目目录

10.4.2 持久层(Dao)

• 账户实体类

package cn.guardwhy.domain;
/**
 * 账户实体类
 */
@Data
@NoArgsConstructor
@AllArgsConstructor
public class Account {
    
    
    private Integer id;
    private String name;
    private Float money;
}

10.4.3 执行操作

package cn.guardwhy.jdbc;

import cn.guardwhy.domain.Account;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.RowMapper;

import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.List;

/**
 * spring JdbcTemplate实现完整CRUD操作
 */
public class JdbcTemplateCRUD {
    
    
    public static void main(String[] args) {
    
    
        // 1.加载spring配置文件,创建spring IOC容器
        ApplicationContext context = new ClassPathXmlApplicationContext("classpath:bean.xml");
        // 2.从spring IOC容器中,获取JdbcTemplate
        JdbcTemplate jdbcTemplate = (JdbcTemplate) context.getBean("jdbcTemplate");
        // 3.查询多行
        List<Account> list = jdbcTemplate.query("select id,name,money from account", 
        new RowMapper<Account>() {
    
    
            @Override
            public Account mapRow(ResultSet rs, int index) throws SQLException {
    
    
                // 创建账户对象
                Account account = new Account();
                account.setId(rs.getInt("id"));
                account.setName(rs.getString("name"));
                account.setMoney(rs.getFloat("money"));
                return account;
            }
        });
        // 4.打印结果集
        for(Account account:list){
    
    
            System.out.println(account);
        }
        // 5.查询一行一列
        System.out.println("查询一行一列-------");
        Integer accountNum = jdbcTemplate.queryForObject("select count(*) from account", 
        Integer.class);
        System.out.println("当前账户数量:" + accountNum);
    }
}

10.4.4 执行结果

10.4.5 自定义RowMapper

package cn.guardwhy.resources;

import cn.guardwhy.domain.Account;
import org.springframework.jdbc.core.RowMapper;

import java.sql.ResultSet;
import java.sql.SQLException;


public class AccountRowMapper implements RowMapper<Account> {
    
    
    /**
     * 结果集映射的方法：
     *      结果集中的每一行记录，都会调用一次该方法
     */
    public Account mapRow(ResultSet rs, int index) throws SQLException{
    
    
        // 创建账户对象
        Account account = new Account();
        account.setId(rs.getInt("id"));
        account.setName(rs.getString("name"));
        account.setMoney(rs.getFloat("money"));
        return account;
    }
}

10.4.6 执行操作

package cn.guardwhy.jdbc;

import cn.guardwhy.domain.Account;
import cn.guardwhy.resources.AccountRowMapper;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.springframework.jdbc.core.JdbcTemplate;
import java.util.List;

/**
 * spring JdbcTemplate实现完整CRUD操作
 */
public class JdbcTemplateCRUD {
    
    
    public static void main(String[] args) {
    
    
        // 1.加载spring配置文件,创建spring IOC容器
        ApplicationContext context = new ClassPathXmlApplicationContext("classpath:bean.xml");
        // 2.从spring IOC容器中,获取JdbcTemplate
        JdbcTemplate jdbcTemplate = (JdbcTemplate) context.getBean("jdbcTemplate");
        // 3.使用自定义的RowMapper
        List<Account> list = jdbcTemplate.query("select * from account",
         new AccountRowMapper());

        // 4.打印结果集
        for(Account account:list){
    
    
            System.out.println(account);
        }
        // 5.查询一行一列
        System.out.println("查询一行一列-------");
        Integer accountNum = jdbcTemplate.queryForObject("select count(*) from account",
        Integer.class);
        System.out.println("当前账户数量:" + accountNum);
    }
}

10.5 JdbcTemplate整合数据源

10.5.1 常见数据源

#在使用JdbcTemplate的时候，需要设置一个数据源对象，才能完成数据库操作
#常见的数据源：
	内置数据源：
		org.springframework.jdbc.datasource.DriverManagerDataSource
		
	c3p0数据源：
		com.mchange.v2.c3p0.ComboPooledDataSource
		
	dbcp数据源：
		org.apache.commons.dbcp.BasicDataSource
	
	druid数据源：
		com.alibaba.druid.pool.DruidDataSource

10.5.2 整合内置数据源

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
       http://www.springframework.org/schema/beans/spring-beans.xsd">

    <!--配置JdbcTemplate-->
    <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
        <!--注入数据源对象-->
        <property name="dataSource" ref="dataSource"></property>
    </bean>

    <!--配置数据源对象-->
    <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
        <!--注入连接数据库的四个基本要素-->
        <property name="driverClassName" value="com.mysql.jdbc.Driver"></property>
        <property name="url" value="jdbc:mysql://127.0.0.1:3306/1_spring"></property>
        <property name="username" value="root"></property>
        <property name="password" value="admin"></property>
    </bean>

</beans>

10.5.3 整合c3p0数据源

10.5.3.1 项目结构

10.5.3.2 配置pom.xml

<!--c3p0版本-->
<c3p0.version>0.9.5</c3p0.version>

<!--c3p0依赖-->
<dependency>
    <groupId>com.mchange</groupId>
    <artifactId>c3p0</artifactId>
    <version>${c3p0.version}</version>
</dependency>

10.5.3.3 配置bean.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"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans.xsd">

    <!--配置JdbcTemplate-->
    <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
        <!--注入数据源对象-->
        <property name="dataSource" ref="dataSource"></property>
    </bean>

    <!--配置数据源(c3p0)对象-->
    <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
        <!--注入连接数据库-->
        <property name="driverClass" value="com.mysql.jdbc.Driver"></property>
        <property name="jdbcUrl" value="jdbc:mysql://127.0.0.1:3306/spring"></property>
        <property name="user" value="root"></property>
        <property name="password" value="root"></property>
    </bean>
</beans>

10.5.3.4 执行结果

10.5.4 整合druid数据源

10.5.4.1 项目结构

10.5.4.2 配置pom.xml

<!--druid版本-->
<druid.version>1.0.29</druid.version>

<!--druid依赖-->
<dependency>
      <groupId>com.alibaba</groupId>
      <artifactId>druid</artifactId>
      <version>${druid.version}</version>
</dependency>

10.5.4.3 配置bean.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"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans.xsd">

    <!--配置JdbcTemplate-->
    <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
        <!--注入数据源对象-->
        <property name="dataSource" ref="dataSource"></property>
    </bean>

    <!--配置数据源对象(druid)-->
    <bean id="dataSource" class="com.alibaba.druid.pool.DruidDataSource">
        <!--注入连接数据库-->
        <property name="driverClassName" value="com.mysql.jdbc.Driver"></property>
        <property name="url" value="jdbc:mysql://127.0.0.1:3306/spring"></property>
        <property name="username" value="root"></property>
        <property name="password" value="root"></property>
    </bean>
</beans>

10.5.4.4 执行结果