在java web開發過程中，難免會有一些系統異常或人為產生一些異常。在RESTful springboot 項目中如何優雅的處理？
分析：在RESTful 風格的springboot 項目中，返回的都是body 對象，所以定義一個結果基類，其中包含status,message,data(請求方法的返回結果),是比較合適的。
如果定義多個異常類進行處理，會比較麻煩。比如StudentNotExistsException、StudentExistsException。 。 。等，並且不能指定錯誤碼，不方便前端根據錯誤碼進行處理。
說明：一般的spring mvc模型處理流程如下
一般controller層-> Service層-> Dao層。
1.controller層，接受請求，進行分頁，DTO對象封裝操作。
2.service層，執行邏輯，控制並發，事務。
3.Dao層，與數據庫交互。
使用一個學生表的處理進行說明：
1、定義常見的錯誤枚舉StudentExceptionEnum
public enum StudentExceptionEnum { STUDENT_NOT_EXIST(1004,"學生不存在，請確認後再查"), STUDENT_EXIST(1005,"學生已存在"); private Integer status; private String comment; StudentExceptionEnum(Integer status, String comment) { this.status = status; this.comment = comment; } public Integer getStatus() { return status; } public void setStatus(Integer status) { this.status = status; } public String getComment() { return comment; } public void setComment(String comment) { this.comment = comment; }}2 定義一個基本的處理結果類RequestResult
@Datapublic class RequestResult { private String message; private Integer status; private Object data; public RequestResult(String message, Integer status, Object data) { this.message = message; this.status = status; this.data = data; } public RequestResult(String message, Integer status) { this.message = message; this.status = status; } public RequestResult(String message, StudentExceptionEnum requestExceptionEnum) { this.message = message; this.status = requestExceptionEnum.getStatus(); } public RequestResult() { status = 200; message = "ok"; } public static RequestResult OK(Object data) { RequestResult result = new RequestResult(); result.setData(data); return result; } public static RequestResult EXCEPTION(String message, Integer status) { return new RequestResult(message, status); } public static RequestResult EXCEPTION(String message, StudentExceptionEnum requestExceptionEnum) { return new RequestResult(message, requestExceptionEnum); }}3 實體類Student
@Datapublic class Student implements Serializable{ private String id; private String nickname; private String name; private int age; private String sex; private String address; @Override public String toString() { return ToStringBuilder.reflectionToString(this); }}4 處理請求，添加學生，nickname 必填項。此處只顯示Service 片段代碼
@Override public RequestResult addStudent(Student student) { if (studentDao.queryIdByNickname(student.getNickname()) == null) { studentDao.addStudent(student); System.out.println("添加成功"); student = studentDao.queryByNickname(student.getNickname()); return RequestResult.OK(student); } else { return RequestResult.EXCEPTION("用戶" + student.getNickname() + "已存在", StudentExceptionEnum.STUDENT_EXIST); } }5 此時，已經完成了基本的處理情況。下面就進行基本的測試了
5.1 添加一個新同學信息
5.2 再次添加讓其出現異常測試
二、到此基本已大功告成，但是，對於基本的運行時異常沒有處理，直接返回給前端會很不友好。所以要定義一個全局的RuntimeException 異常處理類。
此處需要使用的關鍵標註： @ExceptionHandler
用法有兩種1）在處理請求的Controller 中添加@ExceptionHandler，此時該方法只會處理該Controller 拋出的異常。
2）將其用在全局的異常處理類中，全局異常處理類需要使用@RestControllerAdvice 或@ControllerAdvice 標記
我們需要處理全局的RuntimeException，所以我們使用第二種方法。當然，這樣處理是為了客戶友好型，我們還是要處理這種錯誤，怎麼辦？就需要將錯誤的信息記錄下來，方便以後分析處理。此處使用logger 進行記錄。代碼如下
@RestControllerAdvicepublic class BaseExceptionHandler { private static Logger logger = LoggerFactory.getLogger(BaseExceptionHandler.class); @ExceptionHandler(value = RuntimeException.class) public RequestResult exceptionHandler(HttpServletRequest request,Exception e) { logError(request,e); return RequestResult.EXCEPTION("內部處理異常，工程師正在抓緊搶修，請稍後再來...",500); } public static void logError(HttpServletRequest request, Exception e) { logger.error("請求地址：" + request.getRequestURL()); logger.error("請求方法：" + request.getMethod()); logger.error("請求IP：" + getRemoteIp(request)); logger.error("錯誤詳情："); StackTraceElement[] error = e.getStackTrace(); for (StackTraceElement stackTraceElement : error) { logger.error(stackTraceElement.toString()); } } public static String getRemoteIp(HttpServletRequest request) { String ip = request.getHeader("X-Forwarded-For"); if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) { if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) { ip = request.getHeader("Proxy-Client-IP"); } if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) { ip = request.getHeader("WL-Proxy-Client-IP"); } if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) { ip = request.getHeader("HTTP_CLIENT_IP"); } if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) { ip = request.getHeader("HTTP_X_FORWARDED_FOR"); } if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) { ip = request.getRemoteAddr(); } } else if (ip.length() > 15) { String[] ips = ip.split(","); for (int index = 0; index < ips.length; index++) { String strIp = (String) ips[index]; if (!("unknown".equalsIgnoreCase(strIp))) { ip = strIp; break; } } } return ip; }}進行測試看是否生效：
修改添加學生信息代碼如下：
public RequestResult addStudent(Student student) { int a = 1/0; if (studentDao.queryIdByNickname(student.getNickname()) == null) { studentDao.addStudent(student); System.out.println("添加成功"); student = studentDao.queryByNickname(student.getNickname()); return RequestResult.OK(student); } else { return RequestResult.EXCEPTION("用戶'" + student.getNickname() + "'已存在", StudentExceptionEnum.STUDENT_EXIST); } }進行測試
後台打印錯誤信息
2018-03-26 17:01:19.125 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : 請求地址：http://localhost:8080/demo1/student2018-03-26 17:01:19.125 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : 請求方法：POST2018-03-26 17:01:19.125 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : 請求IP：0:0:0:0:0:0:0:12018-03-26 17:01:19.125 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : 錯誤詳情：2018-03-26 17:01:19.125 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : com.huitong.demo.service.StudentService.addStudent(StudentService.java:71)2018-03-26 17:01:19.125 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : com.huitong.demo.controller.StudentController.addStudent(StudentController.java:38)2018-03-26 17:01:19.125 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)2018-03-26 17:01:19.125 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)2018-03-26 17:01:19.125 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)2018-03-26 17:01:19.125 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : java.lang.reflect.Method.invoke(Method.java:498)2018-03-26 17:01:19.125 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:209)2018-03-26 17:01:19.125 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:136)2018-03-26 17:01:19.125 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:102)2018-03-26 17:01:19.125 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:870)2018-03-26 17:01:19.125 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:776)2018-03-26 17:01:19.125 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87)2018-03-26 17:01:19.129 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:991)2018-03-26 17:01:19.129 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:925)2018-03-26 17:01:19.129 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:978)2018-03-26 17:01:19.129 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:881)2018-03-26 17:01:19.129 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : javax.servlet.http.HttpServlet.service(HttpServlet.java:661)2018-03-26 17:01:19.129 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:855)2018-03-26 17:01:19.130 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : javax.servlet.http.HttpServlet.service(HttpServlet.java:742)2018-03-26 17:01:19.130 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231)2018-03-26 17:01:19.130 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)2018-03-26 17:01:19.130 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)2018-03-26 17:01:19.130 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)2018-03-26 17:01:19.130 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)2018-03-26 17:01:19.130 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : com.alibaba.druid.support.http.WebStatFilter.doFilter(WebStatFilter.java:123)2018-03-26 17:01:19.130 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)2018-03-26 17:01:19.130 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)2018-03-26 17:01:19.130 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:99)2018-03-26 17:01:19.130 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)2018-03-26 17:01:19.130 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)2018-03-26 17:01:19.130 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)2018-03-26 17:01:19.130 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : org.springframework.web.filter.HttpPutFormContentFilter.doFilterInternal(HttpPutFormContentFilter.java:109)2018-03-26 17:01:19.130 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)2018-03-26 17:01:19.130 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)2018-03-26 17:01:19.131 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)2018-03-26 17:01:19.131 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:81)2018-03-26 17:01:19.131 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)2018-03-26 17:01:19.131 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)2018-03-26 17:01:19.131 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)2018-03-26 17:01:19.131 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:200)2018-03-26 17:01:19.131 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)2018-03-26 17:01:19.131 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)2018-03-26 17:01:19.131 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)2018-03-26 17:01:19.131 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:199)2018-03-26 17:01:19.131 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96)2018-03-26 17:01:19.131 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:496)2018-03-26 17:01:19.131 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140)2018-03-26 17:01:19.131 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:81)2018-03-26 17:01:19.131 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87)2018-03-26 17:01:19.131 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:342)2018-03-26 17:01:19.131 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:803)2018-03-26 17:01:19.131 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)2018-03-26 17:01:19.131 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:790)2018-03-26 17:01:19.131 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1459)2018-03-26 17:01:19.131 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)2018-03-26 17:01:19.131 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)2018-03-26 17:01:19.131 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)2018-03-26 17:01:19.131 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)2018-03-26 17:01:19.131 ERROR 9136 --- [nio-8080-exec-2] chdcontroller.BaseExceptionHandler : java.lang.Thread.run(Thread.java:745)2018-03-26 17:01:19.133 WARN 9136 --- [nio-8080-exec-2] .mmaExceptionHandlerExceptionResolver : Resolved exception caused by Handler execution: java.lang.ArithmeticException: / by zero
總結
以上所述是小編給大家介紹的springboot 錯誤處理小結，希望對大家有所幫助，如果大家有任何疑問請給我留言，小編會及時回復大家的。在此也非常感謝大家對武林網網站的支持！