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Spring系列【3】应用构造器注入法实现Bean的注入

package cn.com.xf;public class User {    private String name;    private int age;    private String remark;            //省略setter/getter方法    @Override    public String toString() {        return "User [name=" + name + ", age=" + age + ", remark=" + remark                + "]";    }}
package cn.com.xf;public class UserUtil {    private User user;    public User getUser() {        return user;    }                //注意这个构造方法    public UserUtil(User u){        this.user=u;    }        public boolean isUser() {        if (user != null) {            return true;        } else {            return false;        }    }}

以下是Spring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-2.0.xsd">    <bean id="user" class="cn.com.xf.User">        <property name="name" value="jikoy"></property>        <property name="age" value="28"></property>        <property name="remark" value="this is remark"></property>    </bean>    <bean id="userUtil" class="cn.com.xf.UserUtil">        <constructor-arg ref="user"></constructor-arg>    </bean></beans>

以上,我跟前一篇不一样,没有使用P标签,但效果是一样的,注意 <constructor-arg ref="user"></constructor-arg>

package cn.com.xf;import org.springframework.context.ConfigurableApplicationContext;import org.springframework.context.support.ClassPathXmlApplicationContext;public class Test {    public static void main(String[] args) {        ConfigurableApplicationContext ctx=new ClassPathXmlApplicationContext("applicationContext.xml");        User user=(User) ctx.getBean("user");        ctx.close();        System.out.println(user);    }}

测试类仍是使用了ApplicationContext的子接口方法,并提供了关闭方法。

Spring系列【3】应用构造器注入法实现Bean的注入