依赖注入-构造方法注入

通过构造方法注入，就相当于给构造方法的参数传值。

一、编写CustomerDao接口

package com.yiidian.dao;
/*** * @author http://www.yiidian.com**/
public interface CustomerDao {public void save();
}

二、编写CustomerDaoImp实现类

package com.yiidian.dao.impl;import com.yiidian.dao.CustomerDao;
/*** @author http://www.yiidian.com**/
public class CustomerDaoImpl implements CustomerDao {@Overridepublic void save() {System.out.println("CustomerDaoImpl被成功注入！");}}

三、编写CustomerService接口

package com.yiidian.service;
/*** * @author http://www.yiidian.com**/
public interface CustomerService {public void save();
}

四、编写CustomerServiceImpl实现类

package com.yiidian.service.impl;import com.yiidian.dao.CustomerDao;
import com.yiidian.service.CustomerService;
/*** * @author http://www.yiidian.com**/
public class CustomerServiceImpl implements CustomerService {private CustomerDao customerDao;//关键在这里，提供CustomerDao作为参数的构造方法，待会在配置文件进行注入public CustomerServiceImpl(CustomerDao customerDao) {super();this.customerDao = customerDao;}@Overridepublic void save() {customerDao.save();}}

五、配置applicationContext.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"xmlns:p="http://www.springframework.org/schema/p"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"><bean id="customerDao" class="com.yiidian.dao.impl.CustomerDaoImpl"></bean><bean id="customerService" class="com.yiidian.service.impl.CustomerServiceImpl"><!-- index:代表构造方法参数的索引，0代表第一个参数，以此类推ref: 代表引用另一个bean对象--><constructor-arg index="0" ref="customerDao"></constructor-arg></bean></beans>

六、测试

package com.yiidian.test;import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;import com.yiidian.service.CustomerService;/*** @author http://www.yiidian.com* */
public class Demo1 {@Testpublic void test1() {ApplicationContext context = new ClassPathXmlApplicationContext("applicationContext.xml");CustomerService customerService = (CustomerService)context.getBean("customerService");customerService.save();}}

七、运行结果

spring注入方式有哪些，

源码下载：http://pan.baidu.com/s/1bpxv8Ur