java - 将 Request 范围对象注入(inject) @Aspect

Question

我有一个 Spring AOP Aspect 类，每次调用服务时都会记录日志，我计划在日志中打印更多信息，这次每个请求都会有唯一的标识符，该标识符存储在请求范围内对象直到服务返回。我尝试将请求对象注入(inject)到@Aspect中，但似乎效果不佳。

如果只有一个建议，它会在我调用该服务时起作用，如果我添加更多建议，则会出现错误。(问题结束)

@Aspect
public class LoggingAspect {

    private Logger log = Logger.getLogger(getClass());

    @Autowired
    public RequestScopeObject params;

    @Pointcut("within(net.company.dao..*)")
    private void clDaoLayer() {

    }

    private String uniqueIdentifier(){
       String uid = "";

       if(this.params!=null && this.params.getId()!= null){
          uid = "ID:"+this.params.getId()+" ";
       }else{
          uid = "";
       }
       return uid;
   }

    @Around("clDaoLayer()")
    public Object clDaoLayerAdvice(ProceedingJoinPoint joinPoint)
            throws Throwable {
        String TAG = uniqueIdentifier();
        // gets the system property dynamically for debugging purpose.
        this.printObject = Boolean.parseBoolean(System.getProperty("printobject"));
        Date start = new Date();
        String methodInExcecuting = getSignature(joinPoint);
        log.debug(TAG+"calling method.." + methodInExcecuting
                + " with arguments : " + Arrays.toString(joinPoint.getArgs()));
        Object result = null;
        String slug = "";
        try {
            result = joinPoint.proceed();
        } catch (Exception e) {
            log.error(TAG+" Exception .." + methodInExcecuting, e);
            throw e;
        }
        try {
            if (printObject == true) {
                if (result == null) {
                    slug = " null ";
                } else if (result instanceof List) {
                    slug = ((List) result).toString() + "\n"
                            + ((List) result).size() + "";
                } else if (result.getClass().toString().indexOf("[L") >= 0) {// if
                                                                                // array
                                                                                // get
                                                                                // length
                    slug = ArrayUtils.toString(result) + ". "
                            + ArrayUtils.getLength(result);
                } else if (result != null) {
                    slug = result.toString() + ". 1 value ";
                }
                slug += "\nvalues/rows returned.";
            } else {
                slug = "";
            }
        } catch (Exception e) {
            log.debug(TAG+"Error getting slug..");
        }
        Date end = new Date();
        log.debug(TAG+" Time taken: "
                + (end.getTime() - start.getTime()) + " milliseconds."+"returning from " + methodInExcecuting + ". " + slug);
        return result;
    }

}

日志中的错误

java.lang.reflect.UndeclaredThrowableException
    at org.jboss.ws.core.server.ServiceEndpointInvoker.invoke(ServiceEndpointInvoker.java:228)
    at org.jboss.wsf.stack.jbws.RequestHandlerImpl.processRequest(RequestHandlerImpl.java:474)
    at org.jboss.wsf.stack.jbws.RequestHandlerImpl.handleRequest(RequestHandlerImpl.java:295)
    at org.jboss.wsf.stack.jbws.RequestHandlerImpl.doPost(RequestHandlerImpl.java:205)
    at org.jboss.wsf.stack.jbws.RequestHandlerImpl.handleHttpRequest(RequestHandlerImpl.java:131)
    at org.jboss.wsf.common.servlet.AbstractEndpointServlet.service(AbstractEndpointServlet.java:85)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.jboss.web.tomcat.filters.ReplyHeaderFilter.doFilter(ReplyHeaderFilter.java:96)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:235)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
    at org.jboss.web.tomcat.security.SecurityAssociationValve.invoke(SecurityAssociationValve.java:190)
    at org.jboss.web.tomcat.security.JaccContextValve.invoke(JaccContextValve.java:92)
    at org.jboss.web.tomcat.security.SecurityContextEstablishmentValve.process(SecurityContextEstablishmentValve.java:126)
    at org.jboss.web.tomcat.security.SecurityContextEstablishmentValve.invoke(SecurityContextEstablishmentValve.java:70)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
    at org.jboss.web.tomcat.service.jca.CachedConnectionValve.invoke(CachedConnectionValve.java:158)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:330)
    at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:829)
    at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:598)
    at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447)
    at java.lang.Thread.run(Thread.java:662)
Caused by: java.lang.StackOverflowError
    at java.util.Date.<init>(Date.java:146)
    at net.LoggingAspect.restClientHelperAdvice(LoggingAspect.java:134)
    at sun.reflect.GeneratedMethodAccessor317.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
    at java.lang.reflect.Method.invoke(Method.java:597)
    at org.springframework.aop.aspectj.AbstractAspectJAdvice.invokeAdviceMethodWithGivenArgs(AbstractAspectJAdvice.java:621)
    at org.springframework.aop.aspectj.AbstractAspectJAdvice.invokeAdviceMethod(AbstractAspectJAdvice.java:610)
    at org.springframework.aop.aspectj.AspectJAroundAdvice.invoke(AspectJAroundAdvice.java:65)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
    at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:90)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
    at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:202)
    at $Proxy593.getId(Unknown Source)

Answer 1

我使用 ThreadLocal 的帮助来维护我想要打印的信息。我使用静态变量来保存线程局部变量

public class WorkThreadLocal {

    public static ThreadLocal<String> id = new ThreadLocal<String>(){
        @Override
        protected String initialValue()
        {
            return "";
        }
    };

}

更新后的 LogginAspect.java 如下

@Aspect
public class LoggingAspect {

    private Logger log = Logger.getLogger(getClass());

    @Autowired
    public RequestScopeObject params;

    @Pointcut("within(net.company.dao..*)")
    private void clDaoLayer() {

    }

    private String uniqueIdentifier(){
       String uid = "";
       if (WorkThreadLocal.mwi != null) {
         uid = WorkThreadLocal.id.get() + " ";
       }
       return uid;
    }

    @Around("clDaoLayer()")
    public Object clDaoLayerAdvice(ProceedingJoinPoint joinPoint)
            throws Throwable {
        String TAG = uniqueIdentifier();
        // gets the system property dynamically for debugging purpose.
        this.printObject = Boolean.parseBoolean(System.getProperty("printobject"));
        Date start = new Date();
        String methodInExcecuting = getSignature(joinPoint);
        log.debug(TAG+"calling method.." + methodInExcecuting
                + " with arguments : " + Arrays.toString(joinPoint.getArgs()));
        Object result = null;
        String slug = "";
        try {
            result = joinPoint.proceed();
        } catch (Exception e) {
            log.error(TAG+" Exception .." + methodInExcecuting, e);
            throw e;
        }
        try {
            if (printObject == true) {
                if (result == null) {
                    slug = " null ";
                } else if (result instanceof List) {
                    slug = ((List) result).toString() + "\n"
                            + ((List) result).size() + "";
                } else if (result.getClass().toString().indexOf("[L") >= 0) {// if
                                                                                // array
                                                                                // get
                                                                                // length
                    slug = ArrayUtils.toString(result) + ". "
                            + ArrayUtils.getLength(result);
                } else if (result != null) {
                    slug = result.toString() + ". 1 value ";
                }
                slug += "\nvalues/rows returned.";
            } else {
                slug = "";
            }
        } catch (Exception e) {
            log.debug(TAG+"Error getting slug..");
        }
        Date end = new Date();
        log.debug(TAG+" Time taken: "
                + (end.getTime() - start.getTime()) + " milliseconds."+"returning from " + methodInExcecuting + ". " + slug);
        return result;
    }

}