SpringBoot异常处理

一、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

controller

package com.by.controller;import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;@Controller
public class ExceptionController {@RequestMapping("/Exception1")public String Exception1(){String str = null;str.length();return "index";}@RequestMapping("Exception2")public String Exception2(){int a = 10/0;return "index";}
}

html页面中使用到了thymeleaf，需要引入依赖

<dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-thymeleaf</artifactId></dependency>

自定义错误页面

<!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>

二、整合web访问全局异常处理器

1.处理思路

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 GlobalException implements HandlerExceptionResolver {@Overridepublic ModelAndView resolveException(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) {ModelAndView modelAndView = new ModelAndView();if(ex instanceof ArithmeticException){modelAndView.setViewName("error1");}else if(ex instanceof NullPointerException){modelAndView.setViewName("error2");}modelAndView.addObject("error",ex.toString());return modelAndView;}
}

3.错误页面

error1.html

<!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="${error}"></span>
</body>
</html>

error2.html

<!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="${error}"></span>
</body>
</html>

测试：

创建controller类

package com.by.controller;import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;@Controller
public class ExceptionController {@RequestMapping("/Exception1")public String Exception1(){String str = null;str.length();return "index";}@RequestMapping("Exception2")public String Exception2(){int a = 10/0;return "index";}
}

测试结果

三、整合ajax全局异常处理

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;@ControllerAdvice
public class AjaxException {/*** 处理全局异常* @param exception   异常* @return Map<String, Object>*/@ResponseBody@ExceptionHandler(value = Exception.class)public Map<String, Object> errorHandler(Exception exception) {Map<String, Object> map = new HashMap<>();map.put("status", 500);map.put("msg", exception.getMessage());return map;}
}

测试：

异常注销，无异常时，正常返回