spring-Bean属性的依赖注入-01构造器注入

方式一：构造器注入【利用构造方法注入】

public class User { private String name; private int age; private double money; //满参构造方法 public User(String name, int age, Double money) { this.name = name; this.age = age; this.price = money; } //重写toString方法 @Override public String toString() { return "User{" + "name='" + name + '\'' + ", age=" + age + ", money=" + money + '}'; } }

applicationContext.xml【全局配置文件】

<?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd"> <bean id="user" class="com.bean.User" > <!-- 要赋的值： name=张三 age=12 money=20 index:根据索引选择属性 type:根据属性数据类型选择属性 name:根据属性名选择属性 ref:注入复杂属性值【例如注入一个对象】 value：要给属性赋的值 --> <constructor-arg index="0" value="张三"/> <constructor-arg name="age" value="18"/> <constructor-arg type="java.lang.Double" value="23.5"/> </bean> </beans>

测试方法

@Test public void test() { ApplicationContext ca = new ClassPathXmlApplicationContext("applicationContext.xml"); //通过id从工厂获取Bean User user = (User) ca.getBean("user"); System.out.println("user = " + user); }

注入成功！