SpringBoot中通过ApplicationContext获取RedisTemplate对象提示为空指针异常

爱被打了一巴掌 2022-12-08 12:55 255阅读 0赞

1、定义一个工具类

package com.example.redis.utils;
    
    import com.example.redis.DemoApplication;
    import org.springframework.beans.BeansException;
    import org.springframework.boot.SpringApplication;
    import org.springframework.boot.autoconfigure.SpringBootApplication;
    import org.springframework.context.ApplicationContext;
    import org.springframework.context.ApplicationContextAware;
    import org.springframework.context.ConfigurableApplicationContext;
    import org.springframework.stereotype.Component;
    
    @Component
    public class ApplicationContextUtils implements ApplicationContextAware{
        //放置在获取bean的时候提示空指针，将其定义为静态变量
        private static ApplicationContext context;
    
       //类初始化完成之后调用setApplicationContext()方法进行操作
        @Override
        public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
            ApplicationContextUtils.context = applicationContext;
        }
    
       public static ApplicationContext geteContext(){
            return context;
        }
    
       public static Object getBean(String beanName){
            //在这一步的时候一定要注意，此时可调用这个方法的时候
            //context可能为空，会提示空指针异常，需要将其定义成静态的，这样类加载的时候
            //context就已经存在了
            return context.getBean(beanName);
        }
    }

2、调用getBean方法，同时注意此时getBean方法中的参数首字母要小写，否则报错

RedisTemplate<Object,Object> redisTemplate =
                        (RedisTemplate<Object,Object>) ApplicationContextUtils.getBean("redisTemplate");
            //对key进行序列化
            redisTemplate.setKeySerializer(new StringRedisSerializer());
            redisTemplate.setHashKeySerializer(new StringRedisSerializer());
            redisTemplate.opsForHash().put(id.toString(),key.toString(),value);