关于SpringBoot使用Redis空指针的问题（不能成功注入的问题）

自己的一个小项目使用redis在一个类里可以注入成功，而在另一个类以却不能注入成功

不多bb直接上代码

package com.common.utils;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.BoundListOperations;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.stereotype.Component;
import org.springframework.util.CollectionUtils;

import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.TimeUnit;

@Component
public class RedisUtil {

 @Autowired
 private RedisTemplate<String, Object> redisTemplate;

 public RedisUtil(RedisTemplate<String, Object> redisTemplate) {
  this.redisTemplate = redisTemplate;
 }

 /**
  * 指定缓存失效时间
  * @param key 键
  * @param time 时间(秒)
  * @return
  */
 public boolean expire(String key,long time){
  try {
   if(time>0){
    redisTemplate.expire(key, time, TimeUnit.SECONDS);
   }
   return true;
  } catch (Exception e) {
   e.printStackTrace();
   return false;
  }
 }

 /**
  * 根据key 获取过期时间
  * @param key 键 不能为null
  * @return 时间(秒) 返回0代表为永久有效
  */
 public long getExpire(String key){
  return redisTemplate.getExpire(key,TimeUnit.SECONDS);
 }

 /**
  * 判断key是否存在
  * @param key 键
  * @return true 存在 false不存在
  */
 public boolean hasKey(String key){
  try {
   return redisTemplate.hasKey(key);
  } catch (Exception e) {
   e.printStackTrace();
   return false;
  }
 }

 /**
  * 删除缓存
  * @param key 可以传一个值 或多个
  */
 @SuppressWarnings("unchecked")
 public void del(String ... key){
  if(key!=null&&key.length>0){
   if(key.length==1){
    redisTemplate.delete(key[0]);
   }else{
    redisTemplate.delete(CollectionUtils.arrayToList(key));
   }
  }
 }

 //============================String=============================
 /**
  * 普通缓存获取
  * @param key 键
  * @return 值
  */
 public Object get(String key){
  return key==null?null:redisTemplate.opsForValue().get(key);
 }

 /**
  * 普通缓存放入
  * @param key 键
  * @param value 值
  * @return true成功 false失败
  */
 public boolean set(String key,Object value) {
  try {
   redisTemplate.opsForValue().set(key, value);
   return true;
  } catch (Exception e) {
   e.printStackTrace();
   return false;
  }
 }

 /**
  * 普通缓存放入并设置时间
  * @param key 键
  * @param value 值
  * @param time 时间(分钟) time要大于0 如果time小于等于0 将设置无限期
  * @return true成功 false 失败
  */
 public boolean set(String key,Object value,long time){
  try {
   if(time>0){
    redisTemplate.opsForValue().set(key, value, time, TimeUnit.MINUTES);
   }else{
    set(key, value);
   }
   return true;
  } catch (Exception e) {
   e.printStackTrace();
   return false;
  }
 }

 /**
  * 递增
  * @param key 键
  * @param delta 要增加几(大于0)
  * @return
  */
 public long incr(String key, long delta){
  if(delta<0){
   throw new RuntimeException("递增因子必须大于0");
  }
  return redisTemplate.opsForValue().increment(key, delta);
 }

 /**
  * 递减
  * @param key 键
  * @param delta 要减少几(小于0)
  * @return
  */
 public long decr(String key, long delta){
  if(delta<0){
   throw new RuntimeException("递减因子必须大于0");
  }
  return redisTemplate.opsForValue().increment(key, -delta);
 }

 //================================Map=================================
 /**
  * HashGet
  * @param key 键 不能为null
  * @param item 项 不能为null
  * @return 值
  */
 public Object hget(String key,String item){
  return redisTemplate.opsForHash().get(key, item);
 }

 /**
  * 获取hashKey对应的所有键值
  * @param key 键
  * @return 对应的多个键值
  */
 public Map<Object,Object> hmget(String key){
  return redisTemplate.opsForHash().entries(key);
 }

 /**
  * HashSet
  * @param key 键
  * @param map 对应多个键值
  * @return true 成功 false 失败
  */
 public boolean hmset(String key, Map<String,Object> map){
  try {
   redisTemplate.opsForHash().putAll(key, map);
   return true;
  } catch (Exception e) {
   e.printStackTrace();
   return false;
  }
 }

 /**
  * HashSet 并设置时间
  * @param key 键
  * @param map 对应多个键值
  * @param time 时间(秒)
  * @return true成功 false失败
  */
 public boolean hmset(String key, Map<String,Object> map, long time){
  try {
   redisTemplate.opsForHash().putAll(key, map);
   if(time>0){
    expire(key, time);
   }
   return true;
  } catch (Exception e) {
   e.printStackTrace();
   return false;
  }
 }

 /**
  * 向一张hash表中放入数据,如果不存在将创建
  * @param key 键
  * @param item 项
  * @param value 值
  * @return true 成功 false失败
  */
 public boolean hset(String key,String item,Object value) {
  try {
   redisTemplate.opsForHash().put(key, item, value);
   return true;
  } catch (Exception e) {
   e.printStackTrace();
   return false;
  }
 }

 /**
  * 向一张hash表中放入数据,如果不存在将创建
  * @param key 键
  * @param item 项
  * @param value 值
  * @param time 时间(秒) 注意:如果已存在的hash表有时间,这里将会替换原有的时间
  * @return true 成功 false失败
  */
 public boolean hset(String key,String item,Object value,long time) {
  try {
   redisTemplate.opsForHash().put(key, item, value);
   if(time>0){
    expire(key, time);
   }
   return true;
  } catch (Exception e) {
   e.printStackTrace();
   return false;
  }
 }

 /**
  * 删除hash表中的值
  * @param key 键 不能为null
  * @param item 项 可以使多个 不能为null
  */
 public void hdel(String key, Object... item){
  redisTemplate.opsForHash().delete(key,item);
 }

 /**
  * 判断hash表中是否有该项的值
  * @param key 键 不能为null
  * @param item 项 不能为null
  * @return true 存在 false不存在
  */
 public boolean hHasKey(String key, String item){
  return redisTemplate.opsForHash().hasKey(key, item);
 }

 /**
  * hash递增 如果不存在,就会创建一个 并把新增后的值返回
  * @param key 键
  * @param item 项
  * @param by 要增加几(大于0)
  * @return
  */
 public double hincr(String key, String item,double by){
  return redisTemplate.opsForHash().increment(key, item, by);
 }

 /**
  * hash递减
  * @param key 键
  * @param item 项
  * @param by 要减少记(小于0)
  * @return
  */
 public double hdecr(String key, String item,double by){
  return redisTemplate.opsForHash().increment(key, item,-by);
 }

 //============================set=============================
 /**
  * 根据key获取Set中的所有值
  * @param key 键
  * @return
  */
 public Set<Object> sGet(String key){
  try {
   return redisTemplate.opsForSet().members(key);
  } catch (Exception e) {
   e.printStackTrace();
   return null;
  }
 }

 /**
  * 根据value从一个set中查询,是否存在
  * @param key 键
  * @param value 值
  * @return true 存在 false不存在
  */
 public boolean sHasKey(String key,Object value){
  try {
   return redisTemplate.opsForSet().isMember(key, value);
  } catch (Exception e) {
   e.printStackTrace();
   return false;
  }
 }

 /**
  * 将数据放入set缓存
  * @param key 键
  * @param values 值 可以是多个
  * @return 成功个数
  */
 public long sSet(String key, Object...values) {
  try {
   return redisTemplate.opsForSet().add(key, values);
  } catch (Exception e) {
   e.printStackTrace();
   return 0;
  }
 }

 /**
  * 将set数据放入缓存
  * @param key 键
  * @param time 时间(秒)
  * @param values 值 可以是多个
  * @return 成功个数
  */
 public long sSetAndTime(String key,long time,Object...values) {
  try {
   Long count = redisTemplate.opsForSet().add(key, values);
   if(time>0) {
    expire(key, time);
   }
   return count;
  } catch (Exception e) {
   e.printStackTrace();
   return 0;
  }
 }

 /**
  * 获取set缓存的长度
  * @param key 键
  * @return
  */
 public long sGetSetSize(String key){
  try {
   return redisTemplate.opsForSet().size(key);
  } catch (Exception e) {
   e.printStackTrace();
   return 0;
  }
 }

 /**
  * 移除值为value的
  * @param key 键
  * @param values 值 可以是多个
  * @return 移除的个数
  */
 public long setRemove(String key, Object ...values) {
  try {
   Long count = redisTemplate.opsForSet().remove(key, values);
   return count;
  } catch (Exception e) {
   e.printStackTrace();
   return 0;
  }
 }
 //===============================list=================================

 /**
  * 获取list缓存的内容
  * @param key 键
  * @param start 开始
  * @param end 结束 0 到 -1代表所有值
  * @return
  */
 public List<Object> lGet(String key, long start, long end){
  try {
   return redisTemplate.opsForList().range(key, start, end);
  } catch (Exception e) {
   e.printStackTrace();
   return null;
  }
 }

 /**
  * 获取list缓存的长度
  * @param key 键
  * @return
  */
 public long lGetListSize(String key){
  try {
   return redisTemplate.opsForList().size(key);
  } catch (Exception e) {
   e.printStackTrace();
   return 0;
  }
 }

 /**
  * 通过索引 获取list中的值
  * @param key 键
  * @param index 索引 index>=0时， 0 表头，1 第二个元素，依次类推；index<0时，-1，表尾，-2倒数第二个元素，依次类推
  * @return
  */
 public Object lGetIndex(String key,long index){
  try {
   return redisTemplate.opsForList().index(key, index);
  } catch (Exception e) {
   e.printStackTrace();
   return null;
  }
 }

 /**
  * 将list放入缓存
  * @param key 键
  * @param value 值
  * @return
  */
 public boolean lSet(String key, Object value) {
  try {
   redisTemplate.opsForList().rightPush(key, value);
   return true;
  } catch (Exception e) {
   e.printStackTrace();
   return false;
  }
 }

 /**
  * 将list放入缓存
  * @param key 键
  * @param value 值
  * @param time 时间(秒)
  * @return
  */
 public boolean lSet(String key, Object value, long time) {
  try {
   redisTemplate.opsForList().rightPush(key, value);
   if (time > 0) {
    expire(key, time);
   }
   return true;
  } catch (Exception e) {
   e.printStackTrace();
   return false;
  }
 }

 /**
  * 将list放入缓存
  * @param key 键
  * @param value 值
  * @return
  */
 public boolean lSet(String key, List<Object> value) {
  try {
   redisTemplate.opsForList().rightPushAll(key, value);
   return true;
  } catch (Exception e) {
   e.printStackTrace();
   return false;
  }
 }

 /**
  * 将list放入缓存
  * @param key 键
  * @param value 值
  * @param time 时间(秒)
  * @return
  */
 public boolean lSet(String key, List<Object> value, long time) {
  try {
   redisTemplate.opsForList().rightPushAll(key, value);
   if (time > 0) {
    expire(key, time);
   }
   return true;
  } catch (Exception e) {
   e.printStackTrace();
   return false;
  }
 }

 /**
  * 根据索引修改list中的某条数据
  * @param key 键
  * @param index 索引
  * @param value 值
  * @return
  */
 public boolean lUpdateIndex(String key, long index,Object value) {
  try {
   redisTemplate.opsForList().set(key, index, value);
   return true;
  } catch (Exception e) {
   e.printStackTrace();
   return false;
  }
 }

 /**
  * 移除N个值为value
  * @param key 键
  * @param count 移除多少个
  * @param value 值
  * @return 移除的个数
  */
 public long lRemove(String key,long count,Object value) {
  try {
   Long remove = redisTemplate.opsForList().remove(key, count, value);
   return remove;
  } catch (Exception e) {
   e.printStackTrace();
   return 0;
  }
 }

 /**
  * 模糊查询获取key值
  * @param pattern
  * @return
  */
 public Set keys(String pattern){
  return redisTemplate.keys(pattern);
 }

 /**
  * 使用Redis的消息队列
  * @param channel
  * @param message 消息内容
  */
 public void convertAndSend(String channel, Object message){
  redisTemplate.convertAndSend(channel,message);
 }

 /**
  * 根据起始结束序号遍历Redis中的list
  * @param listKey
  * @param start 起始序号
  * @param end 结束序号
  * @return
  */
 public List<Object> rangeList(String listKey, long start, long end) {
  //绑定操作
  BoundListOperations<String, Object> boundValueOperations = redisTemplate.boundListOps(listKey);
  //查询数据
  return boundValueOperations.range(start, end);
 }
 /**
  * 弹出右边的值 --- 并且移除这个值
  * @param listKey
  */
 public Object rifhtPop(String listKey){
  //绑定操作
  BoundListOperations<String, Object> boundValueOperations = redisTemplate.boundListOps(listKey);
  return boundValueOperations.rightPop();
 }
}

上面是Redis的配置文件和自定义方法类，下面是调用Redis自定义方法类

package com.common.config;

import org.springframework.cache.annotation.CachingConfigurerSupport;
import org.springframework.cache.annotation.EnableCaching;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.redis.connection.RedisConnectionFactory;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.data.redis.serializer.Jackson2JsonRedisSerializer;
import org.springframework.data.redis.serializer.StringRedisSerializer;

@Configuration
@EnableCaching
public class RedisConfig extends CachingConfigurerSupport{
 /**
  * 配置自定义redisTemplate
  * @return
  */
 @Bean
 RedisTemplate<String, Object> redisTemplate(RedisConnectionFactory redisConnectionFactory) {

  RedisTemplate<String, Object> redisTemplate = new RedisTemplate<>();
  redisTemplate.setConnectionFactory(redisConnectionFactory);
  Jackson2JsonRedisSerializer jackson2JsonRedisSerializer = new Jackson2JsonRedisSerializer(Object.class);
  // 设置值（value）的序列化采用Jackson2JsonRedisSerializer。
  redisTemplate.setValueSerializer(jackson2JsonRedisSerializer);
  // 设置键（key）的序列化采用StringRedisSerializer。
  redisTemplate.setKeySerializer(new StringRedisSerializer());
  redisTemplate.setHashKeySerializer(new StringRedisSerializer());

  redisTemplate.afterPropertiesSet();
  return redisTemplate;
 }
}

上面这个是发送邮件的类，把邮箱存在Redis里方便效验（不用查数据库了），性能更好一点
在这里使用@Autowired和@Configuration可以成功注入Redis和调用其set方法

且redisUtil是有数据的是有数据的
但是我又新写了个业务类名为AddLoginTooken，添加用户登录tooken效验用的

package com.common.utils;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.mail.MailSendException;
import org.springframework.mail.SimpleMailMessage;
import org.springframework.mail.javamail.JavaMailSender;

import java.util.Random;

@Configuration
public class SetMail {

 @Autowired
 RedisTemplate redisTemplate;

 @Autowired
 RedisUtil redisUtil;

 @Autowired
 private JavaMailSender javaMailSender;

 Logger logger = LoggerFactory.getLogger(this.getClass());

 public String sendMail(String mail){
  String checkCode = String.valueOf(new Random().nextInt(899999) + 100000);
  SimpleMailMessage message = new SimpleMailMessage();
  try {
   redisUtil.set(mail, checkCode, 1);
   message.setFrom("742919609@qq.com");
   message.setTo(mail);
   message.setSubject("欢迎成为宠物救助平台的用户");
   message.setText("您的注册验证码为：" + checkCode);

   javaMailSender.send(message);
   logger.info("邮件发送成功");
  } catch (MailSendException e) {
   logger.error("目标邮箱不存在");
  } catch (Exception e) {
   e.printStackTrace();
   logger.error("文本邮件发送异常");
  }
  return checkCode;

 }
}

和那个setMail类一模一样的代码，一模一样的注释，而且都有spring的小图标，说明应该是都注入进去了呀

但是调用这个却有空指针的问题：

package com.common.utils;

import com.pojo.User;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.redis.core.RedisTemplate;
import java.util.Date;
import java.util.UUID;

@Configuration
public class AddLoginTooken {

 @Autowired
 RedisTemplate redisTemplate;

 @Autowired
 RedisUtil redisUtil;

 public User addLoginTicket(User user){

  Date date = new Date();
  date.setTime(date.getTime()+1000*3600*30);
  user.setUser_tooken(UUID.randomUUID().toString().replaceAll("-",""));

  String user_tooken = user.getUser_tooken();
  redisUtil.set("user_tooken", user_tooken);

  return user;

 }

}

debug发现redisUtil为空

我解决他的第一个想法是在Application里加一个扫描

java.lang.NullPointerException
	at com.common.utils.AddLoginTooken.addLoginTicket(AddLoginTooken.java:26)
	at com.service.impl.LoginServiceImpl.login(LoginServiceImpl.java:39)
	at com.controller.LoginController.login(LoginController.java:33)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:190)
	at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:138)
	at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:105)
	at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:879)
	at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:793)
	at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87)
	at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1040)
	at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:943)
	at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006)
	at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:909)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:660)
	at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:741)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
	at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
	at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:100)
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
	at org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:93)
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
	at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201)
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:202)
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96)
	at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:541)
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:139)
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92)
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74)
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343)
	at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:373)
	at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65)
	at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:868)
	at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1590)
	at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
	at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
	at java.lang.Thread.run(Thread.java:748)

但是还是不行，重启IDEA和清缓存都不行

求解

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