Springboot--Exception

    Springboot--Exception 自定义异常类

一   controller

package com.example.demo.Controller;
import org.springframework.stereotype.Controller;
import org.springframework.validation.BindingResult;
import org.springframework.web.bind.annotation.ModelAttribute;
import org.springframework.web.bind.annotation.RequestMapping;



    @Controller
    public class DemoController {

        @RequestMapping("/showdemo")
        public String show(){
            String str = null;
            str.length();
            return "index";
        }

        @RequestMapping("/showdemo2")
        public String show2(){
            int a = 10/0;
            return "index";
        }


    }
二  全局异常处理类

 方式一

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

/**
 * 全局异常处理类
 *
 *
 */
@ControllerAdvice
public class GlobalException {
    /**
     * java.lang.ArithmeticException
     * 该方法需要返回一个ModelAndView：目的是可以让我们封装异常信息以及视图的指定
     * 参数Exception e:会将产生异常对象注入到方法中
     */
    @ExceptionHandler(value={java.lang.ArithmeticException.class})
    public ModelAndView arithmeticExceptionHandler(Exception e){
        ModelAndView mv = new ModelAndView();
        mv.addObject("error", e.toString());
        mv.setViewName("error1");
        return mv;
    }
    
    /**
     * java.lang.NullPointerException
     * 该方法需要返回一个ModelAndView：目的是可以让我们封装异常信息以及视图的指定
     * 参数Exception e:会将产生异常对象注入到方法中
     */
    @ExceptionHandler(value={java.lang.NullPointerException.class})
    public ModelAndView nullPointerExceptionHandler(Exception e){
        ModelAndView mv = new ModelAndView();
        mv.addObject("error", e.toString());
        mv.setViewName("error2");
        return mv;
    }
    
}

1

方式二

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.bind.annotation.ControllerAdvice;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.handler.SimpleMappingExceptionResolver;

/**
 * 通过SimpleMappingExceptionResolver做全局异常处理
 *
 *
 */
@Configuration
public class GlobalException {
    
    /**
     * 该方法必须要有返回值。返回值类型必须是：SimpleMappingExceptionResolver
     */
    @Bean
    public SimpleMappingExceptionResolver getSimpleMappingExceptionResolver(){
        SimpleMappingExceptionResolver resolver = new SimpleMappingExceptionResolver();
        
        Properties mappings = new Properties();
        
        /**
         * 参数一：异常的类型，注意必须是异常类型的全名
         * 参数二：视图名称
         */
        mappings.put("java.lang.ArithmeticException", "error1");
        mappings.put("java.lang.NullPointerException","error2");
        
        //设置异常与视图映射信息的
        resolver.setExceptionMappings(mappings);
        
        return resolver;
    }
    
}

 

方式三

import java.util.Properties;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.bind.annotation.ControllerAdvice;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.servlet.HandlerExceptionResolver;
import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.handler.SimpleMappingExceptionResolver;

/**
 * 通过实现HandlerExceptionResolver接口做全局异常处理
 *
 *
 */
@Configuration
public class GlobalException implements HandlerExceptionResolver {

    @Override
    public ModelAndView resolveException(HttpServletRequest request, HttpServletResponse response, Object handler,
            Exception ex) {
        ModelAndView mv = new ModelAndView();
        //判断不同异常类型，做不同视图跳转
        if(ex instanceof ArithmeticException){
            mv.setViewName("error1");
        }
        
        if(ex instanceof NullPointerException){
            mv.setViewName("error2");
        }
        mv.addObject("error", ex.toString());
        
        return mv;
    }
}

三错误页面

3.1 error.html

    
    


出错了，请与管理员联系。。。
 

3.2 error1.html

    出错了，请与管理员联系。。。
    

3.3error2.html

    出错了，请与管理员联系。。。