1:jdbcTemplate需要依赖数据库连接池,获取数据库连接,然后根据连接好的连接,封装方法,进行增删查改的操作。
例子:使用dbcp数据路连接池,封装jdbc,直接封装。
package com.itheima.b_api;
import org.apache.commons.dbcp.BasicDataSource;
import org.springframework.jdbc.core.JdbcTemplate;
public class TestApi {
public static void main(String[] args) {
//1 创建数据源(连接池) dbcp
BasicDataSource dataSource = new BasicDataSource();
// * 基本4项
dataSource.setDriverClassName("com.mysql.jdbc.Driver");
dataSource.setUrl("jdbc:mysql://localhost:3306/ee19_spring_day02");
dataSource.setUsername("root");
dataSource.setPassword("1234");
//2 创建模板
JdbcTemplate jdbcTemplate = new JdbcTemplate();
jdbcTemplate.setDataSource(dataSource);
//3 通过api操作
jdbcTemplate.update("insert into t_user(username,password) values(?,?);", "tom","998");
}
}
2:将数据库的链接以及ioc和DI都交给spring来操作。
封装userDao依赖jdbcTemplete,jdbcTemplete的实例化交给spring容器来做。
package com.itheima.c_dbcp;
import org.springframework.jdbc.core.JdbcTemplate;
import com.itheima.a_domain.User;
public class UserDao {
//jdbc模板将由spring注入
private JdbcTemplate jdbcTemplate;
public void setJdbcTemplate(JdbcTemplate jdbcTemplate) {
this.jdbcTemplate = jdbcTemplate;
}
public void update(User user){
String sql = "update t_user set username=?,password=? where id =?";
Object[] args = {user.getUsername(),user.getPassword(),user.getId()};
jdbcTemplate.update(sql, args);
}
}
3:配置数据库链接池的配置文件
<?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:aop="http://www.springframework.org/schema/aop"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/aop
http://www.springframework.org/schema/aop/spring-aop.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context.xsd">
<!-- 创建数据源 -->
<bean id="dataSourceId" class="org.apache.commons.dbcp.BasicDataSource">
<property name="driverClassName" value="com.mysql.jdbc.Driver"></property>
<property name="url" value="jdbc:mysql://localhost:3306/ee19_spring_day02"></property>
<property name="username" value="root"></property>
<property name="password" value="1234"></property>
</bean>
<!-- 创建模板 ,需要注入数据源-->
<bean id="jdbcTemplateId" class="org.springframework.jdbc.core.JdbcTemplate">
<property name="dataSource" ref="dataSourceId"></property>
</bean>
<!-- 配置dao -->
<bean id="userDaoId" class="com.itheima.c_dbcp.UserDao">
<property name="jdbcTemplate" ref="jdbcTemplateId"></property>
</bean>
</beans>
4:测试dbcp数据库连接池
package com.itheima.c_dbcp;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import com.itheima.a_domain.User;
public class TestDBCP {
@Test
public void demo01(){
User user = new User();
user.setId(1);
user.setUsername("接客");
user.setPassword("998");
String xmlPath = "com/itheima/c_dbcp/beans.xml";
ApplicationContext applicationContext = new ClassPathXmlApplicationContext(xmlPath);
//获得目标类
UserDao userDao = (UserDao) applicationContext.getBean("userDaoId");
userDao.update(user);
}
}
2:使用c3p0数据库连接池
说明:配置文件做修改其他基本不用动
package com.itheima.d_c3p0;
import java.util.List;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.RowMapper;
import org.springframework.jdbc.core.simple.ParameterizedBeanPropertyRowMapper;
import com.itheima.a_domain.User;
public class UserDao {
//jdbc模板将由spring注入
private JdbcTemplate jdbcTemplate;
public void setJdbcTemplate(JdbcTemplate jdbcTemplate) {
this.jdbcTemplate = jdbcTemplate;
}
public void update(User user){
String sql = "update t_user set username=?,password=? where id =?";
Object[] args = {user.getUsername(),user.getPassword(),user.getId()};
jdbcTemplate.update(sql, args);
}
/**
* 查询所有
* @return
*/
public List<User> findAll() {
return jdbcTemplate.query("select * from t_user", ParameterizedBeanPropertyRowMapper.newInstance(User.class));
}
}
2:添加配置文件
<?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:aop="http://www.springframework.org/schema/aop"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/aop
http://www.springframework.org/schema/aop/spring-aop.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context.xsd">
<!-- 创建数据源 c3p0-->
<bean id="dataSourceId" class="com.mchange.v2.c3p0.ComboPooledDataSource">
<property name="driverClass" value="com.mysql.jdbc.Driver"></property>
<property name="jdbcUrl" value="jdbc:mysql://localhost:3306/ee19_spring_day02"></property>
<property name="user" value="root"></property>
<property name="password" value="1234"></property>
</bean>
<!-- 创建模板 ,需要注入数据源-->
<bean id="jdbcTemplateId" class="org.springframework.jdbc.core.JdbcTemplate">
<property name="dataSource" ref="dataSourceId"></property>
</bean>
<!-- 配置dao -->
<bean id="userDaoId" class="com.itheima.d_c3p0.UserDao">
<property name="jdbcTemplate" ref="jdbcTemplateId"></property>
</bean>
</beans>
3:测试数据库连接池
package com.itheima.d_c3p0;
import java.util.List;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import com.itheima.a_domain.User;
public class TestC3P0 {
@Test
public void demo01(){
String xmlPath = "com/itheima/d_c3p0/beans.xml";
ApplicationContext applicationContext = new ClassPathXmlApplicationContext(xmlPath);
//获得目标类
UserDao userDao = (UserDao) applicationContext.getBean("userDaoId");
List<User> allUser = userDao.findAll();
for (User user : allUser) {
System.out.println(user);
}
}
}
3:使用jdbcDaoSupport实现jdbcTemplete
说明:jdbcDaoSupport源码自动实现了jdbcTemplete的封装,我们要做的就是往userDao中设置数据库连接池就好了。
package com.itheima.e_jdbcdaosupport;
import java.util.List;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.RowMapper;
import org.springframework.jdbc.core.simple.ParameterizedBeanPropertyRowMapper;
import org.springframework.jdbc.core.support.JdbcDaoSupport;
import com.itheima.a_domain.User;
public class UserDao extends JdbcDaoSupport{
public void update(User user){
String sql = "update t_user set username=?,password=? where id =?";
Object[] args = {user.getUsername(),user.getPassword(),user.getId()};
this.getJdbcTemplate().update(sql, args);
}
/**
* 查询所有
* @return
*/
public List<User> findAll() {
return this.getJdbcTemplate().query("select * from t_user", ParameterizedBeanPropertyRowMapper.newInstance(User.class));
}
}
2:配置文件,我们直接配置数据库连接池就行了
<?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:aop="http://www.springframework.org/schema/aop"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/aop
http://www.springframework.org/schema/aop/spring-aop.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context.xsd">
<!-- 创建数据源 c3p0-->
<bean id="dataSourceId" class="com.mchange.v2.c3p0.ComboPooledDataSource">
<property name="driverClass" value="com.mysql.jdbc.Driver"></property>
<property name="jdbcUrl" value="jdbc:mysql://localhost:3306/ee19_spring_day02"></property>
<property name="user" value="root"></property>
<property name="password" value="1234"></property>
</bean>
<!-- 配置dao
* dao 继承 JdbcDaoSupport,之后只需要注入数据源,底层将自动创建模板
-->
<bean id="userDaoId" class="com.itheima.e_jdbcdaosupport.UserDao">
<property name="dataSource" ref="dataSourceId"></property>
</bean>
</beans>
3:使用jdbcTemplete的做测试。
package com.itheima.e_jdbcdaosupport;
import java.util.List;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import com.itheima.a_domain.User;
public class TestC3P0 {
@Test
public void demo01(){
String xmlPath = "com/itheima/e_jdbcdaosupport/beans.xml";
ApplicationContext applicationContext = new ClassPathXmlApplicationContext(xmlPath);
//获得目标类
UserDao userDao = (UserDao) applicationContext.getBean("userDaoId");
List<User> allUser = userDao.findAll();
for (User user : allUser) {
System.out.println(user);
}
}
}
4:测试使用spring-el表达式,集成properties
1:配置userDao
package com.itheima.f_properties;
import java.util.List;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.RowMapper;
import org.springframework.jdbc.core.simple.ParameterizedBeanPropertyRowMapper;
import org.springframework.jdbc.core.support.JdbcDaoSupport;
import com.itheima.a_domain.User;
public class UserDao extends JdbcDaoSupport{
public void update(User user){
String sql = "update t_user set username=?,password=? where id =?";
Object[] args = {user.getUsername(),user.getPassword(),user.getId()};
this.getJdbcTemplate().update(sql, args);
}
/**
* 查询所有
* @return
*/
public List<User> findAll() {
return this.getJdbcTemplate().query("select * from t_user", ParameterizedBeanPropertyRowMapper.newInstance(User.class));
}
public User getById(int id) {
return this.getJdbcTemplate().queryForObject("select * from t_user where id = ?", ParameterizedBeanPropertyRowMapper.newInstance(User.class), id);
}
}
2:配置文件
<context:property-placeholder location="classpath:com/itheima/f_properties/jdbcInfo.properties"/> 加载配置文件,放入spring容器中
<?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:aop="http://www.springframework.org/schema/aop"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/aop
http://www.springframework.org/schema/aop/spring-aop.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context.xsd">
<!-- 加载配置文件
"classpath:"前缀表示 src下
在配置文件之后通过 ${key} 获得内容
-->
<context:property-placeholder location="classpath:com/itheima/f_properties/jdbcInfo.properties"/>
<!-- 创建数据源 c3p0-->
<bean id="dataSourceId" class="com.mchange.v2.c3p0.ComboPooledDataSource">
<property name="driverClass" value="${jdbc.driverClass}"></property>
<property name="jdbcUrl" value="${jdbc.jdbcUrl}"></property>
<property name="user" value="${jdbc.user}"></property>
<property name="password" value="${jdbc.password}"></property>
</bean>
<!-- 配置dao
* dao 继承 JdbcDaoSupport,之后只需要注入数据源,底层将自动创建模板
-->
<bean id="userDaoId" class="com.itheima.f_properties.UserDao">
<property name="dataSource" ref="dataSourceId"></property>
</bean>
</beans>
3:测试使用
package com.itheima.f_properties;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import com.itheima.a_domain.User;
public class TestProps {
@Test
public void demo01(){
String xmlPath = "com/itheima/f_properties/beans.xml";
ApplicationContext applicationContext = new ClassPathXmlApplicationContext(xmlPath);
//获得目标类
UserDao userDao = (UserDao) applicationContext.getBean("userDaoId");
User user = userDao.getById(1);
System.out.println(user);
}
}
4:properties的文件
jdbc.driverClass=com.mysql.jdbc.Driver
jdbc.jdbcUrl=jdbc:mysql://localhost:3306/ee19_spring_day02
jdbc.user=root
jdbc.password=1234
以上jdbcTemplete的介绍就说完了,以及数据库连接池的使用。