java无法注入_解决Springboot @Autowired 无法注入问题

特别提醒：一定要注意文件结构

WebappApplication 一定要在包的最外层，否则Spring无法对所有的类进行托管，会造成@Autowired 无法注入。

1.　　添加工具类获取在 Spring 中托管的 Bean

(1)工具类

package com.common;

import org.springframework.beans.BeansException;

import org.springframework.beans.factory.NoSuchBeanDefinitionException;

import org.springframework.context.ApplicationContext;

import org.springframework.context.ApplicationContextAware;

/**

* @program: IPC_1P

* @description: 获取在spring中托管的bean

* @author: johnny

* @create: 2018-08-03 16:24

**/

public class SpringContextUtil {

private static ApplicationContext applicationContext; // Spring应用上下文

// 下面的这个方法上加了@Override注解，原因是继承ApplicationContextAware接口是必须实现的方法

public static void setApplicationContext(ApplicationContext applicationContext)

throws BeansException {

SpringContextUtil.applicationContext = applicationContext;

}

public static ApplicationContext getApplicationContext() {

return applicationContext;

}

public static Object getBean(String name) throws BeansException {

return applicationContext.getBean(name);

}

public static Object getBean(String name, Class requiredType)

throws BeansException {

return applicationContext.getBean(name, requiredType);

}

public static boolean containsBean(String name) {

return applicationContext.containsBean(name);

}

public static boolean isSingleton(String name)

throws NoSuchBeanDefinitionException {

return applicationContext.isSingleton(name);

}

public static Class getType(String name)

throws NoSuchBeanDefinitionException {

return applicationContext.getType(name);

}

public static String[] getAliases(String name)

throws NoSuchBeanDefinitionException {

return applicationContext.getAliases(name);

}

}

(2)使用

1)程序启动时，实例化 SpringContextUtil

@SpringBootApplication

public class WebappApplication {

private static ApplicationContext applicationContext;

public static void main(String[] args) {

applicationContext = SpringApplication.run(WebappApplication.class, args);

//

SpringContextUtil springContextUtil = new SpringContextUtil();

springContextUtil.setApplicationContext(applicationContext);

System.out.println("服务器启动测试!");

}

2)在使用 @Service 的方法中，通过@Autowired 注入，使用SpringcontexUtil 获取Bean上下文

@Autowired

SenderService senderService;

public class Package_State {

@Autowired

SenderService senderService;

@Component

private Package_State() {

senderService = (SenderService)SpringContextUtil.getBean("senderService");

}

}

总结

以上所述是小编给大家介绍的解决Springboot @Autowired 无法注入问题，希望对大家有所帮助，如果大家有任何疑问请给我留言，小编会及时回复大家的。在此也非常感谢大家对脚本之家网站的支持！