Spring_JDBC的使用

Spring 是个一站式框架：Spring 自身也提供了控制层的 SpringMVC和持久层的 Spring JdbcTemplate。

配置信息

1.下载 Spring JdbcTemplate 的 jar 包,在pom.xml中导入

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-jdbc</artifactId>
            <version>5.2.2.RELEASE</version>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-aspects</artifactId>
            <version>5.2.2.RELEASE</version>
        </dependency>
        <!-- 阿里数据源 -->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid</artifactId>
            <version>1.1.10</version>
        </dependency>

        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.16</version>
        </dependency>

2.配置resource信息

<?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:tx="http://www.springframework.org/schema/tx"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
        https://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/context
        http://www.springframework.org/schema/context/spring-context.xsd
        http://www.springframework.org/schema/tx
        http://www.springframework.org/schema/tx/spring-tx.xsd">

</beans>

3.导入属性文件

<context:property-placeholder location="classpath:config.properties"/>

driverName=com.mysql.cj.jdbc.Driver
url=jdbc:mysql://127.0.0.1:3306/数据库名?serverTimezone=Asia/Shanghai
uname=账户
upassword=密码

4.管理数据源对象

<bean id="dataSource" class="com.alibaba.druid.pool.DruidDataSource">
              <property name="driverClassName" value="${driverName}"></property>
              <property name="url" value="${url}"></property>
              <property name="username" value="${uname}"></property>
              <property name="password" value="${upassword}"></property>
              <property name="initialSize" value="10"></property>
              <property name="minIdle" value="5"></property>
              <property name="maxActive" value="20"></property>
              <property name="maxWait" value="2000"></property>
</bean>

5.在配置文件中创建 JdbcTemplate

<bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
              <property name="dataSource" ref="dataSource"></property>
</bean>

实体类

public class UserDao {
     @Resource
     JdbcTemplate jdbcTemplate;  
}

在类中获得 JdbcTemplate 对象，就可以直接使用。

JdbcTemplate中常用的方法

execute：无返回值，可执行 ddl，增删改语句

update：执行新增、修改、删除语句；

queryForXXX：执行查询相关语句

举例：

jdbcTemplate.update("insert into admin(account,password) value(?,?)","张三","123");

List<User> list = jdbcTemplate.query("select * from admin where id > ?",
                    new RowMapper<User>() {
                        @Override
                        public User mapRow(ResultSet resultSet, int i) throws SQLException {
                            User user = new User();
                            user.setId(resultSet.getInt("id"));
                            user.setName(resultSet.getString("account"));
                            return user;
                        }
                    }, 1);