Spring Boot的异常处理和单元测试

最新推荐文章于 2024-12-30 16:03:28 发布

原创最新推荐文章于 2024-12-30 16:03:28 发布 · 569 阅读

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文章标签：

#spring boot #单元测试 #java

一、Spring Boot异常处理

1.1、自定义错误页面

SpringBoot默认的处理异常的机制：SpringBoot 默认的已经提供了一套处理异常的机制。一旦程序中出现了异常 SpringBoot 会向/error 的 url 发送请求。在 springBoot 中提供了一个叫 BasicErrorController 来处理/error 请求，然后跳转到默认显示异常的页面来展示异常信息

如果我们需要将所有的异常同一跳转到自定义的错误页面，需要再src/main/resources/templates 目录下创建 error.html 页面。注意：名称必须叫 error

1.1.1、controller

package com.by.controller;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.servlet.ModelAndView;

@Controller
public class ExceptionController {
    @RequestMapping("show1")
    public String exception1(){
        String str=null;
        str.length();
     return "exception1";
    }

    @RequestMapping("show2")
    public String exception2(){
        int a=6/0;
        return "exception2";
    }
}

1.1.2、错误页面

<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>错误提示页面</title>
</head>
<body>
	出错了，请与管理员联系。。。
	<span th:text="${error}"></span>
</body>
</html>

1.2、整合web全局异常处理器

1.2.1、处理思路

1.2.2、创建全局异常处理器

package com.by.exception;

import org.springframework.stereotype.Component;
import org.springframework.web.servlet.HandlerExceptionResolver;
import org.springframework.web.servlet.ModelAndView;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
//@Component
public class GlobalExceptionResolver implements HandlerExceptionResolver {

    @Override
    public ModelAndView resolveException(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, Exception e) {
        //发短信、发邮件
        //指定跳转的错误页面
        ModelAndView mv = new ModelAndView();
        if (e instanceof NullPointerException){
            mv.setViewName("exception1");
        }else if (e instanceof ArithmeticException){
           mv.setViewName("exception2");
        }
        mv.addObject("msg",e.toString());
        return mv;
    }
}

1.2.3、错误页面

exception1

<!DOCTYPE html>
<html>
<head>
    <meta charset="UTF-8">
    <title>错误提示页面-NullPointerException</title>
</head>
<body>
出错了，请与管理员联系。。。
<span th:text="${msg}"></span>
</body>
</html>

exception2

<!DOCTYPE html>
<html>
<head>
    <meta charset="UTF-8">
    <title>错误提示页面-ArithmeticException</title>
</head>
<body>
出错了，请与管理员联系。。。
<span th:text="${msg}"></span>
</body>
</html>

1.3、整合ajax全局异常处理

1.3.1、创建全局异常处理器

package com.by.exception;
import org.springframework.web.bind.annotation.ControllerAdvice;
import org.springframework.web.bind.annotation.ExceptionHandler;

import org.springframework.web.bind.annotation.ResponseBody;

import java.util.HashMap;
import java.util.Map;
//Controller增强 报错到异常方法
@ControllerAdvice
public class AjaxGlobalExceptionResolver {

   @ResponseBody
    //异常方法
   @ExceptionHandler
   public Map exceptionHandler(Exception e){
        HashMap<String, Object> map = new HashMap<>();
        map.put("status",500);
        map.put("msg",e.toString());
        return map;
    }
}

controller

package com.by.controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import java.util.HashMap;
import java.util.Map;

@RestController
public class AjaxExceptionController {
    @RequestMapping("/exception3")
    public Map exception3(){
        HashMap<String, Object> map = new HashMap<>();
        map.put("status",200);
        map.put("msg","世界你好");
        int a=6/0;
        return map;
    }
}

二、Spring Boot整合Junit

2.1、Junit启动器

		<!--junit启动器 -->
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-test</artifactId>
		</dependency>

2.2、编写业务代码

dao

package com.by.dao;

public interface UserDao {
    void addUser();
}

package com.by.dao;
import org.springframework.stereotype.Repository;

@Repository
public class UserDaoImpl implements UserDao{
    @Override
    public void addUser() {
        System.out.println("insert into user...");
    }
}

service

package com.by.service;

public interface UserService {

    void addUser();
}

package com.by.service;

import com.by.dao.UserDao;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

@Service
public class UserServiceImpl implements UserService {
@Autowired
private UserDao userDao;

    @Override
    public void addUser() {
        userDao.addUser();
    }
}

web

package com.by.web;
import com.by.SpringJunitApplication;
import com.by.service.UserService;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;

//junit启动springboot
@SpringBootTest(classes = {SpringJunitApplication.class})
public class Servlet {
@Autowired
    private UserService userService;

@Test
    public void addUser(){
    userService.addUser();
}
}

application

package com.by;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class SpringJunitApplication {

    public static void main(String[] args) {
        SpringApplication.run(SpringJunitApplication.class);
    }
}