详解Springboot自定义异常处理

@Bean
  public EmbeddedServletContainerCustomizer containerCustomizer(){
    return new EmbeddedServletContainerCustomizer(){
      @Override
      public void customize(ConfigurableEmbeddedServletContainer container) {
        container.addErrorPages(new ErrorPage(HttpStatus.NOT_FOUND, "/error/404"));
        container.addErrorPages(new ErrorPage(HttpStatus.INTERNAL_SERVER_ERROR, "/error/500"));
        container.addErrorPages(new ErrorPage(java.lang.Throwable.class,"/error/500"));
      }
    };
  }

/**
 * 重写BasicErrorController,主要负责系统的异常页面的处理以及错误信息的显示
 * @see org.springframework.boot.autoconfigure.web.BasicErrorController
 * @see org.springframework.boot.autoconfigure.web.ErrorMvcAutoConfiguration
 *
 * @author Jonathan
 * @version 2016/5/31 11:22
 * @since JDK 7.0+
 */
@Controller
@RequestMapping(value = "error")
@EnableConfigurationProperties({ServerProperties.class})
public class ExceptionController implements ErrorController {

  private ErrorAttributes errorAttributes;

  @Autowired
  private ServerProperties serverProperties;


  /**
   * 初始化ExceptionController
   * @param errorAttributes
   */
  @Autowired
  public ExceptionController(ErrorAttributes errorAttributes) {
    Assert.notNull(errorAttributes, "ErrorAttributes must not be null");
    this.errorAttributes = errorAttributes;
  }


  /**
   * 定义404的ModelAndView
   * @param request
   * @param response
   * @return
   */
  @RequestMapping(produces = "text/html",value = "404")
  public ModelAndView errorHtml404(HttpServletRequest request,
                 HttpServletResponse response) {
    response.setStatus(getStatus(request).value());
    Map<String, Object> model = getErrorAttributes(request,
        isIncludeStackTrace(request, MediaType.TEXT_HTML));
    return new ModelAndView("error/404", model);
  }

  /**
   * 定义404的JSON数据
   * @param request
   * @return
   */
  @RequestMapping(value = "404")
  @ResponseBody
  public ResponseEntity<Map<String, Object>> error404(HttpServletRequest request) {
    Map<String, Object> body = getErrorAttributes(request,
        isIncludeStackTrace(request, MediaType.TEXT_HTML));
    HttpStatus status = getStatus(request);
    return new ResponseEntity<Map<String, Object>>(body, status);
  }

  /**
   * 定义500的ModelAndView
   * @param request
   * @param response
   * @return
   */
  @RequestMapping(produces = "text/html",value = "500")
  public ModelAndView errorHtml500(HttpServletRequest request,
                 HttpServletResponse response) {
    response.setStatus(getStatus(request).value());
    Map<String, Object> model = getErrorAttributes(request,
        isIncludeStackTrace(request, MediaType.TEXT_HTML));
    return new ModelAndView("error/500", model);
  }


  /**
   * 定义500的错误JSON信息
   * @param request
   * @return
   */
  @RequestMapping(value = "500")
  @ResponseBody
  public ResponseEntity<Map<String, Object>> error500(HttpServletRequest request) {
    Map<String, Object> body = getErrorAttributes(request,
        isIncludeStackTrace(request, MediaType.TEXT_HTML));
    HttpStatus status = getStatus(request);
    return new ResponseEntity<Map<String, Object>>(body, status);
  }


  /**
   * Determine if the stacktrace attribute should be included.
   * @param request the source request
   * @param produces the media type produced (or {@code MediaType.ALL})
   * @return if the stacktrace attribute should be included
   */
  protected boolean isIncludeStackTrace(HttpServletRequest request,
                     MediaType produces) {
    ErrorProperties.IncludeStacktrace include = this.serverProperties.getError().getIncludeStacktrace();
    if (include == ErrorProperties.IncludeStacktrace.ALWAYS) {
      return true;
    }
    if (include == ErrorProperties.IncludeStacktrace.ON_TRACE_PARAM) {
      return getTraceParameter(request);
    }
    return false;
  }


  /**
   * 获取错误的信息
   * @param request
   * @param includeStackTrace
   * @return
   */
  private Map<String, Object> getErrorAttributes(HttpServletRequest request,
                          boolean includeStackTrace) {
    RequestAttributes requestAttributes = new ServletRequestAttributes(request);
    return this.errorAttributes.getErrorAttributes(requestAttributes,
        includeStackTrace);
  }

  /**
   * 是否包含trace
   * @param request
   * @return
   */
  private boolean getTraceParameter(HttpServletRequest request) {
    String parameter = request.getParameter("trace");
    if (parameter == null) {
      return false;
    }
    return !"false".equals(parameter.toLowerCase());
  }

  /**
   * 获取错误编码
   * @param request
   * @return
   */
  private HttpStatus getStatus(HttpServletRequest request) {
    Integer statusCode = (Integer) request
        .getAttribute("javax.servlet.error.status_code");
    if (statusCode == null) {
      return HttpStatus.INTERNAL_SERVER_ERROR;
    }
    try {
      return HttpStatus.valueOf(statusCode);
    }
    catch (Exception ex) {
      return HttpStatus.INTERNAL_SERVER_ERROR;
    }
  }

  /**
   * 实现错误路径,暂时无用
   * @see ExceptionMvcAutoConfiguration#containerCustomizer()
   * @return
   */
  @Override
  public String getErrorPath() {
    return "";
  }

}