SSM框架之Spring JdbcTemplate基本使用

目录

1.JdbcTemplate概述

2.JdbcTemplate开发步骤

3.Spring产生JdbcTemplate对象

4.提取jdbc.properties

5.JdbcTemplate简单操作

---

1.JdbcTemplate概述

Spring框架提供的一个对象，是对原始繁琐的JdbcAPI对象的简单封装。spring框架为我们提供了很多的操作模板类。例如：操作关系型数据的JdbcTemplate和HibernateTemplate，操作nosql数据库的RedisTemplate，操作消息队列的JmsTemplate等等。

2.JdbcTemplate开发步骤

• 导入spring-jdbc和spring-tx坐标

<dependency>
  <groupId>org.springframework</groupId>
  <artifactId>spring-jdbc</artifactId>
  <version>5.3.19</version>
</dependency>
<dependency>
  <groupId>org.springframework</groupId>
  <artifactId>spring-tx</artifactId>
  <version>5.3.19</version>
</dependency>

• 创建数据库表和实体

Create tables account（name varchar(20),money double）;

package com.caoyan.domain;

public class Account {
    private String name;
    private double money;

    public String getName() {
        return this.name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public double getMoney() {
        return this.money;
    }

    public void setMoney(double money) {
        this.money = money;
    }

    @Override
    public String toString() {
        return "{" +
                " name='" + getName() + "'" +
                ", money='" + getMoney() + "'" +
                "}";
    }

}

• 创建JdbcTemplate对象
• 执行数据库操作

package com.caoyan.test;

import java.beans.PropertyVetoException;

import com.mchange.v2.c3p0.ComboPooledDataSource;

import org.junit.Test;
import org.springframework.jdbc.core.JdbcTemplate;

public class JdbcTemplateTest {
    @Test
    // 测试JdbcTemplate开发步骤
    public void test1() throws PropertyVetoException {
        // 创建数据源对象
        ComboPooledDataSource dataSource = new ComboPooledDataSource();
        dataSource.setDriverClass("com.mysql.jdbc.Driver");
        dataSource.setJdbcUrl("jdbc:mysql://localhost:3306/test");
        dataSource.setUser("root");
        dataSource.setPassword("123456");
        JdbcTemplate jdbcTemplate = new JdbcTemplate();
        // 设置数据源对象，知道数据库在哪
        jdbcTemplate.setDataSource(dataSource);
        // 执行操作
        int row = jdbcTemplate.update("insert into account values(?,?)", "tom", 5000);
        System.out.println(row);
    }
}

3.Spring产生JdbcTemplate对象

将JdbcTemplate的创建权交给Spring，将数据源DataSource的创建权也交给Spring，在Spring容器内部将数据源DataSource注入到JdbcTemplate模板对象中。

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:context="http://www.springframework.org/schema/context"
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
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context.xsd">
    <!-- 数据源DataSource -->
    <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
        <property name="driverClass" value="com.mysql.jdbc.Driver"/>
        <property name="jdbcUrl" value="jdbc:mysql://localhost:3306/test"/>
        <property name="user" value="root"/>
        <property name="password" value="123456"/>
    </bean>
    <!-- JdbcTemplate -->
    <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
        <property name="dataSource" ref="dataSource"/>
    </bean>
</beans>

@Test
// 测试Spring产生jdbcTemplate对象
public void test2() {
    ApplicationContext app = new ClassPathXmlApplicationContext("applicationContext.xml");
    JdbcTemplate jdbcTemplate = app.getBean(JdbcTemplate.class);
    int row = jdbcTemplate.update("insert into account values(?,?)", "zhangsan", 15000);
    System.out.println(row);
}

4.提取jdbc.properties

jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/test
jdbc.username=root
jdbc.password=123456

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:context="http://www.springframework.org/schema/context"
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
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context.xsd">
    <!-- 加载jdbc.properties -->
    <context:property-placeholder location="classpath:jdbc.properties"/>
    <!-- 数据源DataSource -->
    <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
        <property name="driverClass" value="${jdbc.driver}"/>
        <property name="jdbcUrl" value="${jdbc.url}"/>
        <property name="user" value="${jdbc.username}"/>
        <property name="password" value="${jdbc.password}"/>
    </bean>
    <!-- JdbcTemplate -->
    <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
        <property name="dataSource" ref="dataSource"/>
    </bean>
</beans>

5.JdbcTemplate简单操作

    @Test
    // 查询所有
    public void testQueryAll() {
        List<Account> accountList = jdbcTemplate.query("select*from account",
                new BeanPropertyRowMapper<Account>(Account.class));
        System.out.println(accountList);
    }

    @Test
    // 查询单个
    public void testQueryOne() {
        Account account = jdbcTemplate.queryForObject("select * from account where name=?",
                new BeanPropertyRowMapper<Account>(Account.class), "tom");
        System.out.println(account);
    }

    @Test
    // 计数
    public void testCount() {
        Long count = jdbcTemplate.queryForObject("select count(*) from account", Long.class);
        System.out.println(count);
    }