Spring JdbcTemplate基本使用
文章目录
1.JdbcTemplate概述
它是spring框架中提供的一个对象，是对原始繁琐的Jdbc API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
① 导入spring-jdbc和spring-tx坐标
② 创建数据库表和实体
③ 创建JdbcTemplate对象
④ 执行数据库操作
3.快速入门
1.导入坐标
- spring-context
- c3p0
- junit
-spring-test- mysql-connector-java
- spring-jdbc
- spring-tx
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>5.0.5.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-jdbc</artifactId>
<version>5.0.5.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-tx</artifactId>
<version>5.0.5.RELEASE</version>
</dependency>
<dependency>
<groupId>c3p0</groupId>
<artifactId>c3p0</artifactId>
<version>0.9.1.2</version>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.48</version>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.12</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-test</artifactId>
<version>5.0.5.RELEASE</version>
</dependency>
2.创建表account和实体类Account
建表sql:
CREATE TABLE account(
`oid` int NOT NULL AUTO_INCREMENT ,
`username` VARCHAR(10) NOT NULL,
`money` int NOT NULL,
PRIMARY KEY(`oid`)
)ENGINE=InnoDB DEFAULT CHARSET=utf8;
pojo类:
package com.itspring.pojo;
public class Account {
private int oid;
private String username;
private int money;
public int getMoney() {
return money;
}
public void setMoney(int money) {
this.money = money;
}
@Override
public String toString() {
return "Account{" +
"oid=" + oid +
", username='" + username + '\'' +
", money=" + money +
'}';
}
}
3.创建JdbcTemplate对象,执行数据库操作
package test;
import com.mchange.v2.c3p0.ComboPooledDataSource;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
import java.beans.PropertyVetoException;
import java.sql.SQLException;
@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(value = "classpath:applicationContext.xml")
public class TestJdbcTemplate {
//手动创建JdbcTemplate对象
@Test
public void test1() throws SQLException, PropertyVetoException {
//创建c3p0数据库连接池
ComboPooledDataSource dataSource = new ComboPooledDataSource();
//设置连接参数
dataSource.setDriverClass("com.mysql.jdbc.Driver");
dataSource.setJdbcUrl("jdbc:mysql://localhost:3306/test");
dataSource.setUser("root");
dataSource.setPassword("root");
//创建jdbcTemplate对象
JdbcTemplate jdbcTemplate = new JdbcTemplate();
//给jdbcTemplate对象设置数据源
jdbcTemplate.setDataSource(dataSource);
//插入一条数据
int i = jdbcTemplate.update("insert into account values(?,?,?)", 1, "tom", 2000);
System.out.println(i);
}
}
4. Sprin*生JdbcTemplate对象
我们可以将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模版对象中.
1.创建jdbc.prperties
jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/test
jdbc.user=root
jdbc.password=root
2.配置spring-jdbc.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"
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">
<!--引入jdbc.properties-->
<context:property-placeholder location="jdbc.properties"/>
<!--配置c3p0连接池-->
<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="${jdbc.user}"/>
<property name="password" value="${jdbc.password}"/>
</bean>
<!--配置jdbcTemplate-->
<bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
<property name="dataSource" ref="dataSource"/>
</bean>
</beans>
3.在applicationContext.xml中引入spring-jdbc.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">
<import resource="classpath:spring-jdbc.xml"/>
</beans>
4.创建SpringJunit测试类,并将jdbcTemplate注入
package test;
import com.mchange.v2.c3p0.ComboPooledDataSource;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
import java.beans.PropertyVetoException;
import java.sql.SQLException;
@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(value = "classpath:applicationContext.xml")
public class TestJdbcTemplate {
@Autowired
private JdbcTemplate jdbcTemplate;
//Spring创建jdbcTemplate对象
@Test
public void test2() {
//插入一条数据
int i = jdbcTemplate.update("insert into account values(?,?,?)", 3, "lucy", 5000);
System.out.println(i);
}
}
5. JdbcTemplate常用操作
5.1 CURD操作
注意:
1.如果pojo中没有get/set,那么Springjdbc映射时会找不到属性值,从而为null
2.BeanPropertyRowMapper是RowMapper的实现类public class BeanPropertyRowMapper<T> implements RowMapper<T>
//常用操作操作
@Test
public void test3() {
int i = 0;
//更新操作
i = jdbcTemplate.update("update account set money=? where username =?", 1000, "tom");
System.out.println("update:" + i);
//删除操作
i = jdbcTemplate.update("delete from account where oid = ?", 1);
System.out.println("delete:" + i);
//查询全部
List<Account> accounts = jdbcTemplate.query("select * from account",
new BeanPropertyRowMapper<Account>(Account.class));
AtomicInteger j = new AtomicInteger(1);
accounts.forEach((s) -> {
System.out.println("第" + (j.getAndIncrement()) + "条:" + s);
});
//查询单个
Account account = jdbcTemplate.queryForObject("select * from account where username = ?",
new BeanPropertyRowMapper<Account>(Account.class),"cat");
System.out.println("查询单个" + account);
}