Spring系列之 jdbcTemplate
啥是jdncTemplate?
t他是spring框架中提供的一个对象,是对原始的jdbcAPI对象的简单封装,spring框架为我们提供了很多操作,模板类,比如操作关系型数据库的jdbcTemplate,操作nosql数据库的Redis Template,操作消息队列的jmsTemplate等等
JdbcTemplate开发步骤
1.导入sprign-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
1.导入sprign-jdbc和spring-tx坐标
<dependencies>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-test</artifactId>
<version>5.0.2.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-jdbc</artifactId>
<version>5.0.3.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-tx</artifactId>
<version>5.0.3.RELEASE</version>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.32</version>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.12</version>
</dependency>
<dependency>
<groupId>c3p0</groupId>
<artifactId>c3p0</artifactId>
<version>0.9.1.2</version>
</dependency>
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>druid</artifactId>
<version>1.0.9</version>
</dependency>
</dependencies>
2.创建数据库表和实体
使用sqlyog创建一个表
语句
CREATE TABLE test1(
id INT,
NAME VARCHAR(10)
);
创建实体
package com.pjh;
public class user {
private Integer id;
private String name;
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
@Override
public String toString() {
return "user{" +
"id=" + id +
", name='" + name + '\'' +
'}';
}
}
JbdcTemplate快速入门*,不使用spring框架的时候
@Test
public void test1() throws PropertyVetoException {
ComboPooledDataSource comboPooledDataSource = new ComboPooledDataSource();
comboPooledDataSource.setDriverClass("com.mysql.jdbc.Driver");
comboPooledDataSource.setJdbcUrl("jdbc:mysql://localhost:3309/one");
comboPooledDataSource.setUser("root");
comboPooledDataSource.setPassword("1234");
//创建jdbcTemplate对象
JdbcTemplate jdbcTemplate = new JdbcTemplate();
jdbcTemplate.setDataSource(comboPooledDataSource);
//执行语句
jdbcTemplate.update("insert into test1 values(?,?)",10,"one");
}
结果
抽取配置文件
配置文件代码:
jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3309/one
jdbc.name=root
jdbc.password=1234
测试函数操作
@Test
public void test3() throws PropertyVetoException {
//读取配置文件
ResourceBundle jdbc = ResourceBundle.getBundle("jdbc");
//获取连接池
ComboPooledDataSource comboPooledDataSource = new ComboPooledDataSource();
//设置参数
comboPooledDataSource.setDriverClass(jdbc.getString("jdbc.driver"));
comboPooledDataSource.setJdbcUrl(jdbc.getString("jdbc.url"));
comboPooledDataSource.setUser(jdbc.getString("jdbc.name"));
comboPooledDataSource.setPassword(jdbc.getString("jdbc.password"));
//创建jdbcTemplate对象
JdbcTemplate jdbcTemplate = new JdbcTemplate();
jdbcTemplate.setDataSource(comboPooledDataSource);
jdbcTemplate.update("insert into test1 values(?,?)",13,"three");
}
使用spring创建JdbcTemplate对象
将数据源DataSource与JdbcTemplate的创建权交给Spring并在Spring容器内进行依赖注入
配置代码:
<bean id="datasource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
<property name="driverClass" value="com.mysql.jdbc.Driver"/>
<property name="jdbcUrl" value="jdbc:mysql://localhost:3309/one"/>
<property name="user" value="root"/>
<property name="password" value="1234"/>
</bean>
<bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
<property name="dataSource" ref="datasource"/>
</bean>
测试函数
@Test
public void test2(){
ClassPathXmlApplicationContext classPathXmlApplicationContext =
new ClassPathXmlApplicationContext("applicationContext.xml");
JdbcTemplate jdbcTemplate =(JdbcTemplate) classPathXmlApplicationContext.getBean("jdbcTemplate");
jdbcTemplate.update("insert into test1 values(?,?)",11,"two");
}
结果
成功插入
这个也可以使用读取配置文件的方式
我们首先要导入context的约束路径与命名空间
命名空间: xmlns:context="http://www.springframework.org/schema/context"
约束路径:http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd
配置文件修改
<?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">
<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="${jdbc.name}"/>
<property name="password" value="${jdbc.password}"/>
</bean>
<bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
<property name="dataSource" ref="datasource"/>
</bean>
<context:property-placeholder location="classpath:jdbc.properties"/>
</beans>
测试代码
@Test
public void test4(){
ClassPathXmlApplicationContext classPathXmlApplicationContext =
new ClassPathXmlApplicationContext("applicationContext.xml");
JdbcTemplate jdbcTemplate =(JdbcTemplate) classPathXmlApplicationContext.getBean("jdbcTemplate");
jdbcTemplate.update("insert into test1 values(?,?)",100,"pjh");
}
结果
成功插入
通过注解的方式来得到JdbcTemplate
使用框架
@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration("classpath:applicationContext.xml")
public class test {
@Autowired
private JdbcTemplate jdbcTemplate;
@Test
public void test7(){
jdbcTemplate.update("insert into test1 values(?,?)",110,"GGB");
}
不使用框架
public void test1() throws PropertyVetoException {
ComboPooledDataSource comboPooledDataSource = new ComboPooledDataSource();
comboPooledDataSource.setDriverClass("com.mysql.jdbc.Driver");
comboPooledDataSource.setJdbcUrl("jdbc:mysql://localhost:3309/one");
comboPooledDataSource.setUser("root");
comboPooledDataSource.setPassword("1234");
//创建jdbcTemplate对象
JdbcTemplate jdbcTemplate = new JdbcTemplate();
jdbcTemplate.setDataSource(comboPooledDataSource);
//执行语句
jdbcTemplate.update("insert into test1 values(?,?)",10,"one");
}
由二者对比即可看出框架的巨大好处,上面那么长的代码现在只要几行即可解决
JDBCTemplate的常用操作
查询语句
查询数据库中的所有内容
@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration("classpath:applicationContext.xml")
public class test {
@Autowired
private JdbcTemplate jdbcTemplate;
@Test
public void test8(){
String sql="select * from test1 where name=?";
List<user> query = jdbcTemplate.query(sql, new BeanPropertyRowMapper<user>(user.class));
for (user user : query) {
System.out.println(user);
}
}
结果
查询数据库中的某条内容
@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration("classpath:applicationContext.xml")
public class test {
@Autowired
private JdbcTemplate jdbcTemplate;
@Test
@Test
public void test9(){
String sql="select * from test1 where id=?";
List<user> query = jdbcTemplate.query(sql, new BeanPropertyRowMapper<user>(user.class), 10);
for (user user : query) {
System.out.println(user);
}
}
}
查询数据库记录的数量
@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration("classpath:applicationContext.xml")
public class test {
@Autowired
private JdbcTemplate jdbcTemplate;
@Test
public void test90(){
String sql="select count(*) from test1";
Long aLong = jdbcTemplate.queryForObject(sql, Long.class);
System.out.println("记录条数:"+aLong);
}
}
删除指定记录
@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration("classpath:applicationContext.xml")
public class test {
@Autowired
private JdbcTemplate jdbcTemplate;
@Test
public void test11(){
String sql="delete from test1 where id=11";
jdbcTemplate.update(sql);
}
}