Java 如何使用@Autowired注解自動注入bean

annotationWire.xml （一定記得配置context:annotation-config/）

<?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:p='http://www.springframework.org/schema/p' xsi:schemaLocation='http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context https://www.springframework.org/schema/context/spring-context.xsd'> <context:annotation-config/> <bean p:order='202020124546' /> <bean /></beans>

User類

package com.annotationWire.pojo;import lombok.Data;import org.springframework.beans.factory.annotation.Autowired;@Datapublic class User { private String name; @Autowired private Order order;}

Order類

package com.annotationWire.pojo;import lombok.Data;@Datapublic class Order { private String order;}

測試類

package com.annotationWire;import com.annotationWire.pojo.User;import org.junit.Test;import org.springframework.context.ApplicationContext;import org.springframework.context.support.ClassPathXmlApplicationContext;public class TestAnnotation { @Test public void test(){ApplicationContext applicationContext = new ClassPathXmlApplicationContext('annotationWire.xml');User student = applicationContext.getBean(User.class);System.out.println(student); }}java配置spring，無法@Autowired自動注入bean的問題

要在配置類上加上@ComponentScan

同時在RootConfigure和ServletConfig兩個類上scan的對象是不同的

ServletConfig是用來注冊DispatcherServlet的，它只是用來掃描controller層的

RootConfigure用來注冊ContextLoaderListener，他掃描的范圍是除了controller以外的bean，例如dao，service，bean實體。

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