Spring Boot @ControllerAdvice 处理全局异常，返回固定格式Json

• 需求
  

  在构建RestFul的今天，我们一般会限定好返回数据的格式比如：

  {

  "code": 0,
    "data": {},
    "msg": "操作成功"
  

  }

  但有时却往往会产生一些bug。这时候就破坏了返回数据的一致性，导致调用者无法解析。所以我们常常会定义一个全局的异常拦截器。
  
  注意：ControllerAdvice注解 只拦截Controller 不回拦截 Interceptor的异常

• 介绍
  
  在spring 3.2中，新增了@ControllerAdvice 注解，用于拦截全局的Controller的异常，注意：ControllerAdvice注解只拦截Controller不会拦截Interceptor的异常

• 代码

  package com.cmc.schedule.handler;
  
  import com.gionee.base.entity.JsonResult;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  import org.springframework.beans.ConversionNotSupportedException;
  import org.springframework.beans.TypeMismatchException;
  import org.springframework.http.converter.HttpMessageNotReadableException;
  import org.springframework.http.converter.HttpMessageNotWritableException;
  import org.springframework.web.HttpMediaTypeNotAcceptableException;
  import org.springframework.web.HttpRequestMethodNotSupportedException;
  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 java.io.IOException;
  
  /**
   * 异常拦截处理器
   *
   * @author chenmc
   */
  @ControllerAdvice
  @ResponseBody
  public class GlobalExceptionHandler {
  
      private static final String logExceptionFormat = "Capture Exception By GlobalExceptionHandler: Code: %s Detail: %s";
      private static Logger log = LoggerFactory.getLogger(GlobalExceptionHandler.class);
  
      //运行时异常
      @ExceptionHandler(RuntimeException.class)
      public String runtimeExceptionHandler(RuntimeException ex) {
          return resultFormat(1, ex);
      }
  
      //空指针异常
      @ExceptionHandler(NullPointerException.class)
      public String nullPointerExceptionHandler(NullPointerException ex) {
          return resultFormat(2, ex);
      }
  
      //类型转换异常
      @ExceptionHandler(ClassCastException.class)
      public String classCastExceptionHandler(ClassCastException ex) {
          return resultFormat(3, ex);
      }
  
      //IO异常
      @ExceptionHandler(IOException.class)
      public String iOExceptionHandler(IOException ex) {
          return resultFormat(4, ex);
      }
  
      //未知方法异常
      @ExceptionHandler(NoSuchMethodException.class)
      public String noSuchMethodExceptionHandler(NoSuchMethodException ex) {
          return resultFormat(5, ex);
      }
  
      //数组越界异常
      @ExceptionHandler(IndexOutOfBoundsException.class)
      public String indexOutOfBoundsExceptionHandler(IndexOutOfBoundsException ex) {
          return resultFormat(6, ex);
      }
  
      //400错误
      @ExceptionHandler({HttpMessageNotReadableException.class})
      public String requestNotReadable(HttpMessageNotReadableException ex) {
          System.out.println("400..requestNotReadable");
          return resultFormat(7, ex);
      }
  
      //400错误
      @ExceptionHandler({TypeMismatchException.class})
      public String requestTypeMismatch(TypeMismatchException ex) {
          System.out.println("400..TypeMismatchException");
          return resultFormat(8, ex);
      }
  
      //400错误
      @ExceptionHandler({MissingServletRequestParameterException.class})
      public String requestMissingServletRequest(MissingServletRequestParameterException ex) {
          System.out.println("400..MissingServletRequest");
          return resultFormat(9, ex);
      }
  
      //405错误
      @ExceptionHandler({HttpRequestMethodNotSupportedException.class})
      public String request405(HttpRequestMethodNotSupportedException ex) {
          return resultFormat(10, ex);
      }
  
      //406错误
      @ExceptionHandler({HttpMediaTypeNotAcceptableException.class})
      public String request406(HttpMediaTypeNotAcceptableException ex) {
          System.out.println("406...");
          return resultFormat(11, ex);
      }
  
      //500错误
      @ExceptionHandler({ConversionNotSupportedException.class, HttpMessageNotWritableException.class})
      public String server500(RuntimeException ex) {
          System.out.println("500...");
          return resultFormat(12, ex);
      }
  
      //栈溢出
      @ExceptionHandler({StackOverflowError.class})
      public String requestStackOverflow(StackOverflowError ex) {
          return resultFormat(13, ex);
      }
  
      //其他错误
      @ExceptionHandler({Exception.class})
      public String exception(Exception ex) {
          return resultFormat(14, ex);
      }
  
      private <T extends Throwable> String resultFormat(Integer code, T ex) {
          ex.printStackTrace();
          log.error(String.format(logExceptionFormat, code, ex.getMessage()));
          return JsonResult.failed(code, ex.getMessage());
      }
  
  }  

  package com.cmc.base.entity;
  
  import com.alibaba.fastjson.JSON;
  import lombok.Data;
  
  import java.io.Serializable;
  import java.util.HashMap;
  import java.util.Map;
  
  /**
   * @author chenmc
   * @date 2017/10/12 17:18
   */
  @Data
  public class JsonResult implements Serializable{
  
      private int code;   //返回码 非0即失败
      private String msg; //消息提示
      private Map<String, Object> data; //返回的数据
  
      public JsonResult(){};
  
      public JsonResult(int code, String msg, Map<String, Object> data) {
          this.code = code;
          this.msg = msg;
          this.data = data;
      }
  
      public static String success() {
          return success(new HashMap<>(0));
      }
      public static String success(Map<String, Object> data) {
          return JSON.toJSONString(new JsonResult(0, "解析成功", data));
      }
  
      public static String failed() {
          return failed("解析失败");
      }
      public static String failed(String msg) {
          return failed(-1, msg);
      }
      public static String failed(int code, String msg) {
          return JSON.toJSONString(new JsonResult(code, msg, new HashMap<>(0)));
      }
  
  }
  

  Spring Boot这样就可以了，如果是没用Spring Boot的话，需要在SpringMvc的配置文件中增加下面的配置

  <!-- 处理异常 -->
      <context:component-scan base-package="com.gionee.xo" use-default-filters="false">
  	    <!-- base-package 如果多个，用“,”分隔 -->
  	    <context:include-filter type="annotation" expression="org.springframework.stereotype.Controller" />
  	    <!--控制器增强，使一个Contoller成为全局的异常处理类，类中用@ExceptionHandler方法注解的方法可以处理所有Controller发生的异常-->
  	    <context:include-filter type="annotation" expression="org.springframework.web.bind.annotation.ControllerAdvice" />
  	</context:component-scan>