javaweb 统一异常处理

╰+攻爆jí腚メ 2022-01-15 18:27 253阅读 0赞

项目规范统一是项目长久迭代的根本，规范统一可以让新入职或者新接手的人员能够迅速掌握项目结构，项目的整体设计，快速入手项目，提高开发效率的同时减少我们程序员兄弟的痛苦，今天就说一下异常统一处理，简单来说就是项目做统一处理。下面看一下代码，项目为springboot项目

一、自定义HandlerExceptionResolver 异常拦截，所有throw 出的异常都会经过这里被拦截，然后做统一的返回处理，这里返回的是json格式字符串

package com.activemq.activemq_product.expection;
    
    @Configuration
    public class AgentExceptionResolver implements HandlerExceptionResolver {
    
        @Override
        public ModelAndView resolveException(HttpServletRequest httpServletRequest, HttpServletResponse response, Object o, Exception exception) {
            System.out.println("进来了，，，，，");
            Map<String, Object> map = new HashMap<String, Object>();
            try {
                response.setContentType("application/json;charset=UTF-8");
                PrintWriter writer = response.getWriter();
                map.put("success", false);
                if (exception instanceof CustomException) {
                    map.put("message", exception.getCause().getMessage());
                    map.put("code", exception.getMessage());
                }
                writer.write(JSONObject.toJSONString(map));
                writer.flush();
                writer.close();
                return new ModelAndView("error");
            } catch (IOException e) {
                map.put("message","系统错误");
                //异常中的异常返回到错误页面
                return new ModelAndView("error", map);
            }
        }
    }

二、自定义异常类，作为异常是返回异常类

package com.activemq.activemq_product.expection;
    
    /**
     *统一返回自定义的异常
     */
    public class CustomException extends RuntimeException{
    
    	private static final long serialVersionUID = 1L;
    	
    	public CustomException() {
    		super();
    	}
    
    	public CustomException(String message) {
    		super(message);
    	}
    
    	public CustomException(Throwable cause) {
    		super(cause);
    	}
    
    	public CustomException(String message, Throwable cause) {
    		super(message, cause);
    	}
    
    	public CustomException(String message, Throwable cause,
    						   boolean enableSuppression,
    						   boolean writableStackTrace) {
        	super(message, cause, enableSuppression, writableStackTrace);
        }
        
    }

三、模拟异常测试

@RestController
    public class ProducerController {
    
        Logger logger = LoggerFactory.getLogger(this.getClass());
    
        @RequestMapping("/sendMsg")
        public Map sendMsg(String msg) {
            logger.info("msg==>:"+msg);
            try {
                //模拟异常
                int a = 1/0;
            }catch (Exception e){
                //第一个参数为字符串 ，可以自定义错误码返回，也可以定义其他的，第二个是exception对象，方便查询错误信息。
                throw new CustomException("10000",e);
            }
            Map<String,Object> resultMap = new HashMap<>();
            resultMap.put("msg",msg);
            return resultMap;
        }
    }

此时结果截图： 统一返回格式，错误码，错误信息，是否成功等，根据需要自己进行修改

![20190613155037532.png][]

[20190613155037532.png]: /images/20220115/b0c8127da173403494e6eba7ba9ffd43.png