自定义一个异常类，用户抛出异常后根据组装成前台需要的格式进行返回

1.自定义异常类

package com.ztccloud.naire.exception; import lombok.Data; @Data public class QuestionException extends RuntimeException { / * 异常码 */ private String errorCode; / * 异常信息 */ private String msg; public QuestionException(String errorCode, String message) { super(message); this.errorCode = errorCode; this.msg = message; } public QuestionException() { } public QuestionException(Throwable cause) { super(cause); } public QuestionException(String message) { super(message); this.msg = message; } } 

2.异常处理类

讯享网import com.ztccloud.naire.config.ErrorProperties; import com.ztccloud.naire.vo.Result; import lombok.extern.slf4j.Slf4j; import org.apache.commons.lang3.StringUtils; import org.springframework.util.CollectionUtils; import org.springframework.validation.BindException; import org.springframework.validation.FieldError; import org.springframework.web.bind.MethodArgumentNotValidException; import org.springframework.web.bind.annotation.ExceptionHandler; import org.springframework.web.bind.annotation.RestControllerAdvice; import java.util.List; import java.util.Optional; @Slf4j @RestControllerAdvice//配置一个切面，主要用于Exception public class QuestionExceptionHandler { private static final String DEFAULT_CODE = "ques_500"; private static final String PARAM_NOT_VALID = "ques_501"; private static final String DEFAULT_MSG = "系统异常"; @ExceptionHandler(QuestionException.class)//异常处理器 public Result<String> datacenterExceptionHandler(QuestionException e) { log.error("", e); Result<String> of = Result.of(); String code = e.getErrorCode(); if (StringUtils.isEmpty(code)) { code = DEFAULT_CODE; } return of.setMsg(Optional.ofNullable(ErrorProperties.p.getProperty(code)) .orElseGet(() -> ErrorProperties.p.getProperty(DEFAULT_CODE))) .setCode(code); } @ExceptionHandler(Exception.class) public Result<String> exceptionHandler(Exception e) { log.error("system exception:", e); Result<String> of = Result.of(); return of.setMsg(DEFAULT_MSG).setCode(DEFAULT_CODE); } @ExceptionHandler(MethodArgumentNotValidException.class) public Result<String> paramExceptionHandler(BindException e) { List<FieldError> fieldErrors = e.getFieldErrors(); StringBuilder sb = new StringBuilder(); for (int i = 0; i < fieldErrors.size(); i++) { FieldError error = fieldErrors.get(i); sb.append("[").append("参数:").append(error.getField()).append(" -> ").append(error.getDefaultMessage()).append("]"); if (i != fieldErrors.size() - 1) { sb.append("\r\n"); } } Result<String> of = Result.of(); return of.setMsg(sb.toString()).setCode(PARAM_NOT_VALID); } } 

3.用于捕获filter异常的类

讯享网

import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RestController; import javax.servlet.http.HttpServletRequest; @RestController public class ErrorController { public static final String ERROR_PATH = "/error/throw"; public static final String ATTRIBUTE = "filter.error"; @RequestMapping(ERROR_PATH) public void reThrow(HttpServletRequest request) throws Exception { throw ((Exception) request.getAttribute(ATTRIBUTE)); } }

4.接口统一响应类

讯享网import lombok.Data; import lombok.experimental.Accessors; / * 接口统一响应类 */ @Data @Accessors(chain = true) public class Result<T> { / * 默认返回200, 表示成功处理；其他错误码在统一异常类返回 */ private String code = "200"; / * 返回数据 */ private T data; / * 提示信息 */ private String msg; private Result() { } private Result(String msg) { this.msg = msg; } private Result(T data) { this.data = data; } private Result(T data, String msg) { this.data = data; this.msg = msg; } public static <T> Result<T> of() { return new Result<T>(); } public static <T> Result<T> of(T data) { return new Result<>(data); } public static <T> Result<T> of(T data, String msg) { return new Result<>(data, msg); } } 

然后在项目中，抛出异常，如下在filter中抛出异常

@Override public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws ServletException, IOException { HttpServletRequest httpRequest = (HttpServletRequest) servletRequest; HttpServletResponse httpResponse = (HttpServletResponse) servletResponse; String url = httpRequest.getRequestURI().substring(httpRequest.getContextPath().length()); if (patterns.contains(url)|| StringUtils.containsAny(url,new String[]{"swagger","api-docs"})) { //在白名单中的url,放行访问 filterChain.doFilter(httpRequest, httpResponse); return; } RecordUser user=(RecordUser) httpRequest.getSession().getAttribute(UserControl.SESSION_USER); if (user != null) { //若为登录状态 放行访问 UserControl.setUser(user); filterChain.doFilter(httpRequest, httpResponse); } else { //提示用户未进行登录 try { throw new QuestionException("ques_user_1001","User not logged in！"); } catch (Exception e) { servletRequest.setAttribute(ErrorController.ATTRIBUTE, e); servletRequest.getRequestDispatcher(ErrorController.ERROR_PATH).forward(servletRequest, servletResponse); } } }

加载项目的时候，加载错误信息文件

讯享网@Component public class ErrorProperties { public static Properties p = new Properties(); private static final Logger log = LoggerFactory.getLogger(ErrorProperties.class); @PostConstruct public void parseErrorProperties() throws IOException { log.info("load error.properties ..."); InputStream in = this.getClass().getClassLoader().getResourceAsStream("error.properties"); try { p.load(in); } catch (IOException e) { log.error("load error.properties failed...", e); throw e; } } }