SpringBoot添加全局异常处理器

SpringBoot

1.Application.yml中开启mvc异常处理

spring:
  mvc:
    throw-exception-if-no-handler-found: true

2.启动类添加注解@EnableWebMvc

@SpringBootApplication
@MapperScan("cn.pheker.springbootdemo.mapper")
@ServletComponentScan
@EnableTransactionManagement
@EnableWebMvc
public class WebApplication {
    public static void main(String[] args) {
        SpringApplication.run(WebApplication.class, args);
    }
}

3.全局处理类

package cn.pheker.springbootdemo.config;
import cn.pheker.springbootdemo.utils.Result;
import cn.pheker.springbootdemo.utils.UtilException;
import cn.pheker.springbootdemo.utils.UtilResult;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.validation.FieldError;
import org.springframework.web.HttpRequestMethodNotSupportedException;
import org.springframework.web.bind.MethodArgumentNotValidException;
import org.springframework.web.bind.MissingServletRequestParameterException;
import org.springframework.web.bind.annotation.ControllerAdvice;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.method.annotation.MethodArgumentTypeMismatchException;
import org.springframework.web.servlet.NoHandlerFoundException;
import javax.servlet.http.HttpServletRequest;
import java.util.ArrayList;
import java.util.List;
/**
 * <pre>
 * author    cn.pheker
 * date      2018/3/7  14:25
 * email     1176479642@qq.com
 * desc      全局异常处理器
 *
 * </pre>
 */
@ControllerAdvice
public class GlobalExceptionHandler {
    private Logger logger = LoggerFactory.getLogger(this.getClass());
    @ExceptionHandler(Exception.class)
    @ResponseBody
    public Result<?> jsonErrorHandler(HttpServletRequest request, Exception e) {
        Result result;
        //无此页面或地址
        if(e instanceof NoHandlerFoundException) {//404
            return UtilResult.fail(UtilResult.TYPE.NOT_FOUND, request.getRequestURI());
        }else if(e instanceof HttpRequestMethodNotSupportedException){
            return UtilResult.fail(UtilResult.TYPE.METHOD_NOT_SUPPORTED, request.getRequestURI());
        //缺少参数
        }else if(e instanceof MissingServletRequestParameterException) {
            result = UtilResult.fail(UtilResult.TYPE.PARAMETER_MISS, e.getMessage());
        //参数类型不对或无法转换
        }else if(e instanceof MethodArgumentTypeMismatchException){
            MethodArgumentTypeMismatchException matme = (MethodArgumentTypeMismatchException) e;
            result = UtilResult.fail(UtilResult.TYPE.PARAMETER_NOT_MATCH,matme.getMessage());
        }else if(e instanceof MethodArgumentNotValidException){//参数校验
            List<Result<String>> errorResults = new ArrayList<Result<String>>();
            for (FieldError fieldError : ((MethodArgumentNotValidException) e).getBindingResult().getFieldErrors()) {
                errorResults.add(UtilResult.fail(Integer.parseInt(fieldError.getCode()),fieldError.getDefaultMessage(),
                        fieldError.getField()+fieldError.getRejectedValue()));
            }
            return UtilResult.fail(500,e.getMessage(),errorResults);
        }else{
            result = UtilException.getResult(request, e.getMessage());
            logger.debug(result.toString());
        }
        e.printStackTrace();
        logger.error(e.getMessage());
        return result;
    }
}

以上是采用注解的方法实现的,@ControllerAdvice表示处理Controller，
@ExceptionHandler指明要处理的异常和使用当前方法处理该异常
@ResponseBody表明返回json，不写表明反回页面或ModelAndView

4.也可以采用其它的方式来实现