1、set方法注入
配置：
<bean name="user" class="cn.itcast.bean.User">
<property name="name" value="tom">property>
<property name="age" value="18">property>
<property name="car" ref="car">property>
bean>
<bean name="car" class="cn.itcast.bean.Car">
<property name="name" value="兰博基尼">property>
<property name="color" value="黄色">property>
bean>
//测试demo public class Demo { @Test public void test(){ //1、创建容器对象 ApplicationContext ac =new ClassPathXmlApplicationContext("cn/itcast/injection/applicationContext.xml"); //2、像容器要User对象 User user = (User)ac.getBean("user"); //3、打印user对象 System.out.println(user.toString()); } }
结果：
2、构造方法注入
配置：
<bean name="user1" class="cn.itcast.bean.User">
<constructor-arg name="name" value="jerry">constructor-arg>
<constructor-arg name="car" ref="car">constructor-arg>
bean>
实体：
package cn.itcast.bean; public class User { private String name; private Integer age; private Car car; public User(String name, Car car) { System.out.println("User(String name, Car car)"); this.name = name; this.car = car; } public User(Integer name, Car car) { System.out.println("User(Integer name, Car car)"); this.name = name+""; this.car = car; } public User(){ System.out.println("user对象空参构造"); } public String getName() { return name; } public void setName(String name) { this.name = name; } public Integer getAge() { return age; } public void setAge(Integer age) { this.age = age; } public Car getCar() { return car; } public void setCar(Car car) { this.car = car; } @Override public String toString() { return "User [name=" + name + ", age=" + age + ", car=" + car.toString() + "]"; } }
demo
public class Demo { @Test public void test(){ //1、创建容器对象 ApplicationContext ac =new ClassPathXmlApplicationContext("cn/itcast/injection/applicationContext.xml"); //2、像容器要User对象 User user = (User)ac.getBean("user1"); //3、打印user对象 System.out.println(user.toString()); } }
结果
由 name+index + type 可以任意指定一个构造参数
<bean name="user1" class="cn.itcast.bean.User">
<constructor-arg name="name" index="0" type="java.lang.Integer" value="jerry">constructor-arg>
<constructor-arg name="car" ref="car">constructor-arg>
bean>
3、p名称空间注入
配置
<bean name="user3" class="cn.itcast.bean.User" p:name="jack" p:age="20" p:car-ref="car">
bean>
demo
public class Demo { @Test public void test(){ //1、创建容器对象 ApplicationContext ac =new ClassPathXmlApplicationContext("cn/itcast/injection/applicationContext.xml"); //2、像容器要User对象 User user = (User)ac.getBean("user3"); //3、打印user对象 System.out.println(user.toString()); } }
结果：
4、spel注入
配置:
xml version="1.0" encoding="UTF-8"?>
<beans xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns="http://www.springframework.org/schema/beans"
xmlns:p="http://www.springframework.org/schema/p"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.2.xsd ">
<bean name="user" class="cn.itcast.bean.User">
<property name="name" value="tom">property>
<property name="age" value="18">property>
<property name="car" ref="car">property>
bean>
<bean name="car" class="cn.itcast.bean.Car">
<property name="name" value="兰博基尼">property>
<property name="color" value="黄色">property>
bean>
<bean name="user1" class="cn.itcast.bean.User">
<constructor-arg name="name" index="0" type="java.lang.Integer" value="18">constructor-arg>
<constructor-arg name="car" ref="car">constructor-arg>
bean>
<bean name="user3" class="cn.itcast.bean.User" p:name="jack" p:age="20" p:car-ref="car">
bean>
<bean name="user4" class="cn.itcast.bean.User">
<property name="name" value="#{user.name}">property>
<property name="age" value="#{12}">property>
<property name="car" ref="car">property>
bean>
beans>
demo
public class Demo { @Test public void test(){ //1、创建容器对象 ApplicationContext ac =new ClassPathXmlApplicationContext("cn/itcast/injection/applicationContext.xml"); //2、像容器要User对象 User user = (User)ac.getBean("user4"); //3、打印user对象 System.out.println(user.toString()); } }
结果
