Spring Boot异常处理！！！

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.controller:

java 复制代码

/*
 * Copyright (c) 2020, 2024,  All rights reserved.
 *
 */
package com.by.controller;

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

/**
 * <p>Project: springboot - DomeContorller</p>
 * <p>Powered by scl On 2024-01-15 10:02:34</p>
 * <p>描述：<p>
 *
 * @author 孙臣龙 [1846080280@qq.com]
 * @version 1.0
 * @since 17
 */
@Controller
public class DomeController {

    @RequestMapping("show1")
    public String show1() {
        System.out.println(6 / 0);
        return "error";
    }

    @RequestMapping("show2")
    public String show2() {
        String str=null;
        str.length();
        return "error";
    }
}

2.定义错误页面

error.html:

html 复制代码

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<h1>error1</h1>
出错啦！！！！汗流浃背了！！！
<span th:text="${msg}"></span>
</body>
</html>

error.html:

html 复制代码

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<h1>error2</h1>
出错啦！！！！汗流浃背了！！！
<span th:text="${msg}"></span>
</body>
</html>

3.定义全局异常处理类：

GlobalException：（普通的处理请求）

java 复制代码

/*
 * Copyright (c) 2020, 2024,  All rights reserved.
 *
 */
package com.by.exception;

import org.springframework.context.annotation.ComponentScan;
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;

/**
 * <p>Project: springboot - GlobalException</p>
 * <p>Powered by scl On 2024-01-15 10:11:29</p>
 * <p>描述：<p>
 *
 * @author 孙臣龙 [1846080280@qq.com]
 * @version 1.0
 * @since 17
 */
@Component
public class GlobalException implements HandlerExceptionResolver {

    @Override
    public ModelAndView resolveException(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, Exception e) {
        ModelAndView modelAndView = new ModelAndView();
        if (e instanceof NullPointerException){
            modelAndView.setViewName("error1");
        } else if (e instanceof ArithmeticException) {
            modelAndView.setViewName("error2");
        }
        modelAndView.addObject("msg",e.toString());
        return modelAndView;
    }
}

AjaxGlobalException：（ajax的请求方式，返回的使json数据）

java 复制代码

/*
 * Copyright (c) 2020, 2024,  All rights reserved.
 *
 */
package com.by.exception;

import javafx.beans.property.adapter.ReadOnlyJavaBeanBooleanProperty;
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;

/**
 * <p>Project: springboot - AjaxGlobalException</p>
 * <p>Powered by scl On 2024-01-15 10:48:17</p>
 * <p>描述：<p>
 *
 * @author 孙臣龙 [1846080280@qq.com]
 * @version 1.0
 * @since 17
 */
//@ControllerAdvice
public class AjaxGlobalException {

    @ResponseBody
    @ExceptionHandler
    public Map errorHandler(Exception e){

        Map<String , Object> m = new HashMap<>();
        m.put("status",500);
        m.put("msg",e.toString());

        return m;
    }
}