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springboot博客实战笔记02

news 2025/8/15 8:55:10

一、评论功能：

注意要先登录之后才能进行评论，所有把评论加入到登录拦截器当中

@Overridepublic void addInterceptors(InterceptorRegistry registry) {//拦截test接口，后续实际遇到需要拦截的接口时，在配置为真正的拦截接口registry.addInterceptor(loginInterceptor).addPathPatterns("/test").addPathPatterns("/comments/create/change");}

在登录拦截器LoginInterceptor里面存入了用户信息：

  //登录成功 放行//我希望再controller中 直接获取用户的信息  怎么获取UserThreadLocal.put(sysUser);

后续在评论的实现类里面可以用gei方法获取到用户信息充当评论人

 //这里直接在线程里面找到登录时候保存的用户信息SysUser sysUser = UserThreadLocal.get();

1.根据文章id查询评论

    @Overridepublic Result commentsByArticleId(Long id) {/*** 1.根据文章id 查询评论列表 从comments表中查询-* 2.根据作者的id 查询作者的信息* 3.判断  如果 level = 1 要去查询它有没有子评论* 4.如果 有 根据评论id  进行查询（parent_id）*/LambdaQueryWrapper<Comment> queryWrapper = new LambdaQueryWrapper<>();queryWrapper.eq(Comment::getArticleId,id);queryWrapper.eq(Comment::getLevel,1);List<Comment> comments = commentMapper.selectList(queryWrapper);List<CommentVo> commentVoList = copyList(comments);return Result.success(commentVoList);}

private List<CommentVo> findCommentsByParentId(Long id) {LambdaQueryWrapper<Comment> queryWrapper = new LambdaQueryWrapper<>();queryWrapper.eq(Comment::getParentId,id);queryWrapper.eq(Comment::getLevel,2);List<Comment> comments = commentMapper.selectList(queryWrapper);return copyList(comments);}

将pojo —> vo的方法，这里有个小巧思，分为level大于1和等于1的情况，当level等于1时，说明可能是楼主，会有子评论

private List<CommentVo> copyList(List<Comment> comments) {List<CommentVo> commentVoList = new ArrayList<>();for (Comment comment : comments) {commentVoList.add(copy(comment));}return  commentVoList;}private CommentVo copy(Comment comment) {CommentVo commentVo = new CommentVo();BeanUtils.copyProperties(comment,commentVo);commentVo.setId(String.valueOf(comment.getId()));//作者信息Long authorId = comment.getAuthorId();UserVo userVo = this.sysUserService.findUserVoById(authorId);commentVo.setAuthor(userVo);//子评论Integer level = comment.getLevel();if( 1 == level){Long id = Long.valueOf(comment.getId());List<CommentVo> commentVoList = findCommentsByParentId(id);commentVo.setChildrens(commentVoList);}//to User 给谁评论if(level >1){Long toUid = comment.getToUid();UserVo toUserVo = this.sysUserService.findUserVoById(toUid);commentVo.setToUser(toUserVo);}return commentVo;}

精度损失问题

当数据库用的是分布式id的时候，前端会出现精度损失问题，导致找不到正确的id 此时需要在实体类中,添加相关注解，把id转为string，（分布式id 比较长，传到前端会有精度损失，必须转为string类型，进行运输，就不会有问题了

    //防止前端精度损失 把id转为string@JsonSerialize(using = ToStringSerializer.class)private Long id;

二、发布文章

也需要登录过后才能发布文章，

 registry.addInterceptor(loginInterceptor).addPathPatterns("/test").addPathPatterns("/comments/create/change").addPathPatterns("/articles/publish");

 @Overridepublic Result publish(ArticleParam articleParam) {/*** 1.发布文章  目的 构建Article对象* 2.作者id 当前的登录用户* 3.标签 要将标签加入到 关联表中* 4.body 内容存储**/SysUser sysUser = UserThreadLocal.get();//登录的用户id就是作者id 而登录的用户 可以去线程中找Article article = new Article();article.setAuthorId(Long.valueOf(sysUser.getId()));article.setWeight(Article.Article_Common);article.setViewCounts(0);article.setTitle(articleParam.getTitle());article.setSummary(articleParam.getSummary());article.setCommentCounts(0);article.setCreateDate(System.currentTimeMillis());article.setCategoryId(Long.valueOf(articleParam.getCategory().getId()));//插入之后会生成一个文章idthis.articleMapper.insert(article);//tagList<TagVo> tags = articleParam.getTags();if(tags!=null){for (TagVo tag : tags) {Long articleId = Long.valueOf(article.getId());ArticleTag articleTag = new ArticleTag();articleTag.setTagId(Long.valueOf(tag.getId()));articleTag.setArticleId(articleId);articleTagMapper.insert(articleTag);}}//bodyArticleBody articleBody = new ArticleBody();articleBody.setArticleId(Long.valueOf(article.getId()));articleBody.setContent(articleParam.getBody().getContent());articleBody.setContentHtml(articleParam.getBody().getContentHtml());articleBodyMapper.insert(articleBody);article.setBodyId(Long.valueOf(articleBody.getId()));articleMapper.updateById(article);//方法1 articleVo
//        ArticleVo articleVo = new ArticleVo();
//        articleVo.setId(article.getId());
//        return Result.success(articleVo);//方法2Map<String,String> map = new HashMap<>();map.put("id",article.getId().toString());//返回字符串避免精度损失问题return Result.success(map);}

三、AOP日志

对于 IoC 的一种补充，面向切面编程，简化程序的一种方式
IoC 简化代码量，AOP 实现解耦合的
让代码变得松散，灵活，更方便扩展和维护
日志输出和业务计算混合在一起，耦合在一起，不方便维护
解耦合，把日志输出和业务计算的代码进行分离
最终程序运行的时候，结果还要合到一起

1.在需要记录日志的controller上添加注解

    @PostMapping//加上此注解 代表要对此接口记录日志@LogAnnotation(module="文章",operator="获取文章列表")public Result listArticle(@RequestBody PageParams pageParams){return articleService.listArticle(pageParams);}

2.创建aop包，并且创建annotation类

在这里插入图片描述

package com.mszlu.blog.common.aop;import java.lang.annotation.*;//Type 代表可以放在类上面 Method代表可以放在方法上面
//ElementType.Type ElementType.METHOD
@Target({ElementType.METHOD})
@Retention(RetentionPolicy.RUNTIME)
@Documented
public @interface LogAnnotation {String module() default "";String operator() default "";
}

3.开花AOP创建LogAspect类

package com.mszlu.blog.common.aop;import com.alibaba.fastjson.JSON;
import com.mszlu.blog.common.aop.LogAnnotation;
import com.mszlu.blog.utils.HttpContextUtils;
import com.mszlu.blog.utils.IpUtils;
import lombok.extern.slf4j.Slf4j;
import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Pointcut;
import org.aspectj.lang.reflect.MethodSignature;
import org.springframework.stereotype.Component;import javax.servlet.http.HttpServletRequest;
import java.lang.reflect.Method;@Component//让spring识别到
@Aspect//切面 定义了通知和切点的关系
@Slf4j
public class LogAspect {@Pointcut("@annotation(com.mszlu.blog.common.aop.LogAnnotation)")public void pt(){}@Around("pt()")public Object log(ProceedingJoinPoint joinPoint) throws Throwable {long beginTime = System.currentTimeMillis();//执行方法Object result = joinPoint.proceed();//执行时长(毫秒)long time = System.currentTimeMillis() - beginTime;//保存日志recordLog(joinPoint, time);return result;}private void recordLog(ProceedingJoinPoint joinPoint, long time) {MethodSignature signature = (MethodSignature) joinPoint.getSignature();Method method = signature.getMethod();LogAnnotation logAnnotation = method.getAnnotation(LogAnnotation.class);log.info("=====================log start================================");log.info("module:{}",logAnnotation.module());log.info("operator:{}",logAnnotation.operator());//请求的方法名String className = joinPoint.getTarget().getClass().getName();String methodName = signature.getName();log.info("request method:{}",className + "." + methodName + "()");//        //请求的参数Object[] args = joinPoint.getArgs();String params = JSON.toJSONString(args[0]);log.info("params:{}",params);//获取request 设置IP地址HttpServletRequest request = HttpContextUtils.getHttpServletRequest();log.info("ip:{}", IpUtils.getIpAddr(request));log.info("excute time : {} ms",time);log.info("=====================log end================================");}}

四、上传图片


@RestController
@RequestMapping("upload")
public class UploadController {@Autowiredprivate QiniuUtils qiniuUtils;@PostMapping()public Result upload(@RequestParam("image")MultipartFile file){//原始文件名称 比如aa.pngString originalFilename = file.getOriginalFilename();String fileName = UUID.randomUUID()+toString()+"."+ StringUtils.substringAfterLast(originalFilename,".");//上传文件 上传在哪儿?//七牛云  云服务器 按量付费 幅度快 把图片发到离用户最近的服务器上//降低 我们自身应用服务器的宽带消耗boolean upload = qiniuUtils.upload(file,fileName);if(upload){return Result.success(QiniuUtils.url+fileName);}return Result.fail(20001,"上传失败");}

我们用的平台是七牛云首先先要导入依赖：

 <dependency><groupId>com.qiniu</groupId><artifactId>qiniu-java-sdk</artifactId><version>[7.7.0, 7.7.99]</version></dependency>

QiniuUtils


@Component
public class QiniuUtils {public static  final String url = "http://t0oltruo7.hn-bkt.clouddn.com/";@Value("${qiniu.accessKey}")private  String accessKey;@Value("${qiniu.accessSecretKey}")private  String accessSecretKey;public  boolean upload(MultipartFile file,String fileName){//构造一个带指定 Region 对象的配置类Configuration cfg = new Configuration(Region.huanan());//...其他参数参考类注释UploadManager uploadManager = new UploadManager(cfg);//...生成上传凭证，然后准备上传String bucket = "danb24";//默认不指定key的情况下，以文件内容的hash值作为文件名try {byte[] uploadBytes = file.getBytes();Auth auth = Auth.create(accessKey, accessSecretKey);String upToken = auth.uploadToken(bucket);Response response = uploadManager.put(uploadBytes, fileName, upToken);//解析上传成功的结果DefaultPutRet putRet = JSON.parseObject(response.bodyString(), DefaultPutRet.class);return true;} catch (Exception ex) {ex.printStackTrace();}return false;}
}

注意点

url就是你在七牛云创建的域名 “http://t0oltruo7.hn-bkt.clouddn.com/”;
accessKey和SecretKey在七牛云中获得并且配置在在properties或者直接赋值（不推荐）
qiniu.accessKey=NnneEoseKEAqkNNFuaMYWIBU7gn0xdVUbGuBjmGU
qiniu.accessSecretKey=G5NBjBLd3OdttFet71AGxjbpahwduNpom_amLe1G
bucket 修改为自己的文件名
也可以在配置文件中限制上传文件的值
#上传文件总的最大值
spring.servlet.multipart.max-request-size=20MB
#单个文件的最大值
spring.servlet.multipart.max-file-size=2MB

统一缓存处理（优化）

1.cache包下Cache

package com.mszlu.blog.common.cache;import java.lang.annotation.*;//
@Target({ElementType.METHOD})
@Retention(RetentionPolicy.RUNTIME)
@Documented
public @interface Cache {long expire() default 1 * 60 * 1000;//缓存标识KeyString name() default "";}

2.cache包下CacheAspect

package com.mszlu.blog.common.cache;import com.alibaba.fastjson.JSON;
import com.mszlu.blog.vo.Result;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.codec.digest.DigestUtils;
import org.apache.commons.lang3.StringUtils;
import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.Signature;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Pointcut;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.stereotype.Component;import java.lang.reflect.Method;
import java.time.Duration;
//aop定义了一个切面  切面定义了切点和通知的关系
@Aspect
@Component
@Slf4j
public class CacheAspect {@Autowiredprivate RedisTemplate<String, String> redisTemplate;//切点@Pointcut("@annotation(com.mszlu.blog.common.cache.Cache)")public void pt(){}//环绕@Around("pt()")public Object around(ProceedingJoinPoint pjp){try {Signature signature = pjp.getSignature();//类名String className = pjp.getTarget().getClass().getSimpleName();//调用的方法名String methodName = signature.getName();Class[] parameterTypes = new Class[pjp.getArgs().length];Object[] args = pjp.getArgs();//参数String params = "";for(int i=0; i<args.length; i++) {if(args[i] != null) {params += JSON.toJSONString(args[i]);parameterTypes[i] = args[i].getClass();}else {parameterTypes[i] = null;}}if (StringUtils.isNotEmpty(params)) {//加密 以防出现key过长以及字符转义获取不到的情况params = DigestUtils.md5Hex(params);}Method method = pjp.getSignature().getDeclaringType().getMethod(methodName, parameterTypes);//获取Cache注解Cache annotation = method.getAnnotation(Cache.class);//缓存过期时间long expire = annotation.expire();//缓存名称String name = annotation.name();//先从redis获取String redisKey = name + "::" + className+"::"+methodName+"::"+params;String redisValue = redisTemplate.opsForValue().get(redisKey);if (StringUtils.isNotEmpty(redisValue)){log.info("走了缓存~~~,{},{}",className,methodName);return JSON.parseObject(redisValue, Result.class);}Object proceed = pjp.proceed();redisTemplate.opsForValue().set(redisKey,JSON.toJSONString(proceed), Duration.ofMillis(expire));log.info("存入缓存~~~ {},{}",className,methodName);return proceed;} catch (Throwable throwable) {throwable.printStackTrace();}return Result.fail(-999,"系统错误");}}