记录篇——SpringBoot开发个人博客（一）

2023-12-30 18:46:40

1、创建新项目

2、引入Spring Boot模块

web
Thymeleaf
MySQL

3、配置文件

jpa和mybatis的区别啊，搜了一下，好像大型项目使用mybatis，小型用jpa更好吧

问题：driver-class-name: com.mysql.jdbc.Driver 爆红
解决办法：setting->libraries->+号->导入本地的mysql包即可

application.yml 配置

spring:
  thymeleaf:
    mode: HTML
#    选择使用开发还是生产环境
  profiles:
    active: dev
  messages:
    basename: i18n/messages

comment.avatar: /images/avatar.png

application-dev.yml 生产环境

spring:
  datasource:
    driver-class-name: com.mysql.jdbc.Driver
    url: jdbc:mysql://localhost:3306/blog?useUnicode=true&characterEncoding=utf-8
    username: root
    password: root
  jpa:
    hibernate:
#      自动更新
      ddl-auto: update
#      日志中显示SQL语句
    show-sql: true

#配置日志级别
logging:
  level:
    root: info
    com.lrm: debug
  file:
    name: log/blog-dev.log

application-pro.yml 开发环境

#生产环境
spring:
  datasource:
    driver-class-name: com.mysql.jdbc.Driver
    url: jdbc:mysql://localhost:3306/blog?useUnicode=true&characterEncoding=utf-8
    username: root
    password: root
  jpa:
    hibernate:
      ddl-auto: none
    show-sql: true

logging:
  level:
    root: warn
    com.lrm: info
  file:
    name: log/blog-pro.log


#默认启动为8080
server:
  port: 8080

启动BlogApplication.class，输入127.0.0.1:8080进行查看

4、异常处理

（1）定义一个web控制器

@Controller
public class IndexController {
    @GetMapping("/")
    public String index(){
        return "index";
    }
}

（2）自定义控制异常拦截器 Handler

package com.demo.blog.handler;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.web.bind.annotation.ControllerAdvice;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.servlet.ModelAndView;

import javax.servlet.http.HttpServletRequest;

/**
 *
 * @author demo
 * @date 2021/12/20 13:27
 * @param null
 * @return null
 */
@ControllerAdvice
public class ControllerExceptionHandler {
//    获取日志记录异常
    private final Logger logger = (Logger) LoggerFactory.getLogger(this.getClass());
//    返回一个错误页面
    @ExceptionHandler(Exception.class)//表示只要是Exception级别的就可以拦截
    public ModelAndView exceptionHander(HttpServletRequest request, Exception e) {
//   做一个拦截记录
        logger.error("Request URL : {}, Exception", request.getRequestURL(), e);
        ModelAndView mv = new ModelAndView();
        mv.addObject("url", request.getRequestURI());
        mv.addObject("exception",e);
        //再返回到error页面上
        mv.setViewName("error/error");
        return mv;
    }
}

（3）打开（如图）

5、日志处理

（1）切面编程（aop）

如果@Aspect报错，手动在pom里面添加依赖

  <!-- aop切面 -->
  <dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-aop</artifactId>
  </dependency>

创建一个LogAspect

package com.demo.blog.aspect;
import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.annotation.*;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Component;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;
import javax.servlet.http.HttpServletRequest;
import java.util.Arrays;
/**
 * 
 * @author demo
 * @date 2021/12/20 17:26
 * @param null 
 * @return null
 */
//切面编程（aop）
@Aspect
@Component
public class LogAspect {
    private final Logger logger = LoggerFactory.getLogger(this.getClass());
//    通过@Pointcut注解声明其为一个切面，execution规定切面拦截哪些类
    @Pointcut("execution(* com.demo.blog.web.*.*(..))")
    public void log(){

    }
    @Before("log()")//此方法在切面之前执行
    public void doBefore(JoinPoint joinPoint){
        ServletRequestAttributes attributes = (ServletRequestAttributes) RequestContextHolder.getRequestAttributes();
        HttpServletRequest request = attributes.getRequest();
        String url = request.getRequestURI().toString();
        String ip = request.getRemoteAddr();
        String classMethod = joinPoint.getSignature().getDeclaringTypeName() + "."+ joinPoint.getSignature().getName();
        Object[] args = joinPoint.getArgs();
        RequestLog requestLog = new RequestLog(url,ip,classMethod,args);
         logger.info("Request : {}", requestLog);
    }
    @After("log()")
    public void doAfter(){
//        logger.info("------------doAfter------");
    }
    @AfterReturning(returning = "result",pointcut="log()")
    public void doAfterReturn(Object result){
        logger.info("Result : {}" + result);
    }
    public class RequestLog{
        private String url;//请求URL
        private String ip;//访问者ip
        private String classMethod;//调用方法classMethod
        private Object[] args;//参数args

        public RequestLog(String url, String ip, String classMethod, Object[] args) {
            this.url = url;
            this.ip = ip;
            this.classMethod = classMethod;
            this.args = args;
        }
        @Override
        public String toString() {
            return "{" +
                    "url='" + url + '\'' +
                    ", ip='" + ip + '\'' +
                    ", classMethod='" + classMethod + '\'' +
                    ", args=" + Arrays.toString(args) +
                    '}';
        }
    }
}

（2）IndexController改为：

@GetMapping里传值

（3）启动

6、页面处理（略写）

（1）在引入静态页面之后，使用thymeleaf布局

公共部分放入 _fragments.html 文件

（2）引用

总结：建议先下载源码，再拿出来敲，拿出来看。

jpa和mybatis的区别是什么？
生产和开发环境的配置？
异常处理？
什么是切面编程？

码农公寓