Spring中c3p0连接池的配置 及JdbcTemplate的使用 通过XML配置文件注入各种需要对象的操作 来完成数据库添加Add（）方法

通过配置文件XML方法的配置

可以使用非常简练的Service类

UserService类代码如下：

package com.swift;

public class UserService {
private UserDao userDao;

public void setUserDao(UserDao userDao) {
this.userDao = userDao;
}
public boolean add() {
return userDao.add();
}
}

UserService要调用UserDao中连接数据库的方法add()，需要一个userDao对象，这个对象通过配置文件XML来注入对象，需要setUserDao()来配合

同样UserDao类也非常简练

package com.swift;

import org.springframework.jdbc.core.JdbcTemplate;

public class UserDao {
private JdbcTemplate jdbcTemplate;

public void setJdbcTemplate(JdbcTemplate jdbcTemplate) {
this.jdbcTemplate = jdbcTemplate;
}

public boolean add() {
//        ComboPooledDataSource dataSource=new ComboPooledDataSource();
//        dataSource.setDriverClass("com.mysql.jdbc.Driver");
//        dataSource.setJdbcUrl("jdbc:mysql://localhost:3306/sw_database");
//        dataSource.setUser("root");
//        dataSource.setPassword("root");

String sql="insert into sw_user(username,password) values(?,?)";
int count=jdbcTemplate.update(sql,"弹痕","战侠歌");
if(count==1) {
return true;
}
return false;
}
}

UserDao中要使用JdbcTemplate的对象，这个对象也通过配置文件XML来注入，需要setJdbcTemplate()来配合

而jdbcTemplate对象又需要通过XML在配置中注入dataSource对象

dataSource对象是通过c3p0连接池类得到，需要导入前一篇随笔提供的jar包支持

XML配置文件代码：

<?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/context http://www.springframework.org/schema/context/spring-context.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd">

<!-- c3p0连接池得到dataSource -->
<bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
<property name="driverClass" value="com.mysql.jdbc.Driver"></property>
<property name="jdbcUrl" value="jdbc:mysql://localhost:3306/sw_database"></property>
<property name="user" value="root"></property>
<property name="password" value="root"></property>
</bean>

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

<bean id="userDao" class="com.swift.UserDao">
<property name="jdbcTemplate" ref="jdbcTemplate"></property>
</bean>

<bean id="userService" class="com.swift.UserService">
<property name="userDao" ref="userDao"></property>
</bean>

</beans>

测试类中只要得到XML配置文件对象就可以搞定所有了

代码如下：

package com.swift;

import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

@WebServlet("/test")
public class ServletTest extends HttpServlet {
private static final long serialVersionUID = 1L;

public ServletTest() {
super();
}

protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
response.setCharacterEncoding("utf-8");
response.setContentType("text/html;charset=utf-8");
response.getWriter().append("Served at: ").append(request.getContextPath());

//使用JdbcTemplat的queryForObject方法
ApplicationContext context=new ClassPathXmlApplicationContext("c3p0.xml");
UserService userService= (UserService) context.getBean("userService");
if(userService.add()) {
response.getWriter().append("添加成功！");
}else {
response.getWriter().append("添加失败！");
}
}

protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
doGet(request, response);
}

}

浏览器中结果：



数据库中结果：