关于SpringBoot使用Redis空指针的问题（不能成功注入的问题）
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2022-07-06 13:46:00
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.springframewo...
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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