获取 spring context 然后为所欲为？
执行 tt 命令来记录 RequestMappingHandlerAdapter#invokeHandlerMethod 的请求
tt -t org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter invokeHandlerMethod
请求以后将看到
[arthas@38341]$ tt -t org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter invokeHandlerMethod Press Q or Ctrl+C to abort. Affect(class count: 1 , method count: 1) cost in 60 ms, listenerId: 2 INDEX TIMESTAMP COST(ms) IS-RET IS-EXP OBJECT CLASS METHOD -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- 1000 2021-08-03 15:34:31 473.709743 true false 0x545d772e RequestMappingHandlerAdapter invokeHandlerMethod
可以用 tt 命令的 -i 参数来指定 index，并且用 -w 参数来执行 ognl 表达式来获取 spring context ：
[arthas@38341]$ tt -i 1000 -w 'target.getApplicationContext()' @AnnotationConfigServletWebServerApplicationContext[ reader=@AnnotatedBeanDefinitionReader[org.springframework.context.annotation.AnnotatedBeanDefinitionReader@28aa9b60], scanner=@ClassPathBeanDefinitionScanner[org.springframework.context.annotation.ClassPathBeanDefinitionScanner@1c138ae], annotatedClasses=@LinkedHashSet[isEmpty=true;size=0], basePackages=null, logger=@SLF4JLocationAwareLog[org.apache.commons.logging.impl.SLF4JLocationAwareLog@450746b3], DISPATCHER_SERVLET_NAME=@String[dispatcherServlet], webServer=@TomcatWebServer[org.springframework.boot.web.embedded.tomcat.TomcatWebServer@c5697fe], servletConfig=null, serverNamespace=null, servletContext=@ApplicationContextFacade[org.apache.catalina.core.ApplicationContextFacade@705b6c8f], themeSource=@ResourceBundleThemeSource[org.springframework.ui.context.support.ResourceBundleThemeSource@78d73e62], beanFactory=@DefaultListableBeanFactory[org.springframework.beans.factory.support.DefaultListableBeanFactory@4277127c: defining beans [org.springframework.context.annotatio n.internalConfigurationAnnotationProcessor,org.springframework.context.annotation.internalAutowiredAnnotationProcessor,org.springframework.context.annotation.internalCommonAnno tationProcessor,org.springframework.context.event.internalEventListenerProcessor,org.springframework.context.event.internalEventListenerFactory,mealBootstrapApplication,bootstr apApplicationListener.BootstrapMarkerConfiguration,org.springframework.boot.autoconfigure.internalCachingMetadataReaderFactory,glRocketMQConfig,globalConfig,mybatisPlusConfig,o kHttpConfiguration,mealQueryBaseDataController,mealAppBannerController,appOrderController,mealBannerController,mealReturnCouponsTipsController,appletsOrderController,h5OrderCon troller,thirdNoticeController,aliPayNoticeController,payController,wxPayNoticeController,mealGoodsExclusivePricePcController,mealManagerController,mealOrderManagerController,ba seServiceClient,fileServiceClient,userCenterClient,mealGlobalConfigServiceImpl,mealGoodsCostServiceImpl,mealGoodsCostTableServiceImpl,mealGoodsExclusivePriceServiceImpl,mealBan nerServiceImpl,mealManagerPcServiceImpl,mealOrderManagerPcServiceImpl,mealQueryBaseDataServiceImpl,mealReturnCouponsTipsServiceImpl,internalOrderMq,glCompensationFuncTM,glRocke tMQLocalTM,orderPayResultServiceImpl,orderServiceImpl,orderJobServiceImpl,aliPayConfig,wxAppPayProperties,wxPayConfiguration,aliAppletCyPayServiceImpl,aliPayServiceImpl,mealPay FlowServiceImpl,payProfitSharingFlowServiceImpl,payResultServiceImpl,weChatPayServiceImpl,payFlowHandler,payJobServiceImpl,refundServiceImpl,couponsUtil,idUtils,thirdConfig,goo dsSyncServiceImpl,okHttpUtil,reqUtil,syncGoodsTaskHandler,costTableHandler,mealOrderHandler,payHandler,statisticTaskHandler,globalExceptionHandler,springWebMvcConfiguration,asy ncUtils,feignHystrixConcurrencyStrategy,springSecurityConfiguration,authenticationCustomizeEntryPoint,authAccessDeniedHandler,RBACService,memberExtraInfoClientFallback,memberIn foClientFallback,memberRiskClientFallback,memberWalletClientFallback,memberWalletFlowClientFallback,riskEventClientFallback,userCenterMemberInfoClientFallback,userCenterOperato rClientFallback,constants,utils,captchaClientFallback,channelIsolationClientFallback,channelPriorityClientFallback,complexMessageClientFallback,JPushClientFallback,messageFeish uBotClientFallback,messageFeiShuBotClientV2Fallback,stationLetterClientFallback,idGenerateClientFallback,couponClientFallBack,couponManagerClientFallBack,couponMemberClientFall Back,normalFileClientFallback,transactionAutoConfiguration,webAutoConfiguration,authAutoConfiguration,cacheAutoConfiguration,transactionMQProducer,defaultMQPushConsumer,enumCus tomizer,paginationInterceptor,okHttpClient,x509TrustManager,sslSocketFactory,pool,aliAppPayProperties,aliAppletPayProperties,appAlipayClient,appletAlipayClient,wxAppletPayServi ce,wxAppPayService,org.springframework.boot.context.properties.ConfigurationPropertiesBindingPostProcessor,org.springframework.boot.context.internalConfigurationPropertiesBinde rFactory,org.springframework.boot.context.internalConfigurationPropertiesBinder,org.springframework.boot.context.properties.BoundConfigurationProperties,org.springframework.boo t.context.properties.ConfigurationPropertiesBeanDefinitionValidator,org.springframework.boot.context.properties.ConfigurationBeanFactoryMetadata,wx.applet.pay-com.demo.meal.se rvice.pay.config.WxAppletPayProperties,errorPageRegistrar,corsFilterRegistrationBean,org.springframework.security.config.annotation.configuration.ObjectPostProcessorConfigurati on,objectPostProcessor,org.springframework.security.config.annotation.authentication.configuration.AuthenticationConfiguration,authenticationManagerBuilder,enableGlobalAuthenti cationAutowiredConfigurer,initializeUserDetailsBeanManagerConfigurer,initializeAuthenticationProviderBeanManagerConfigurer,org.springframework.security.config.annotation.web.co nfiguration.WebSecurityConfiguration,delegatingApplicationListener,webSecurityExpressionHandler,springSecurityFilterChain,privilegeEvaluator,conversionServicePostProcessor,auto wiredWebSecurityConfigurersIgnoreParents,org.springframework.security.config.annotation.web.configuration.WebMvcSecurityConfiguration,requestDataValueProcessor,org.springframew ork.scheduling.annotation.SchedulingConfiguration,org.springframework.context.annotation.internalScheduledAnnotationProcessor,org.springframework.boot.autoconfigure.AutoConfigu rationPackages,com.demo.MealBootstrapApplication#MapperScannerRegistrar#0,default.com.demo.MealBootstrapApplication.FeignClientSpecification,memberExtraInfoClient.FeignClient Specification,com.demo.user.common.client.MemberExtraInfoClient,MemberInfoClient.FeignClientSpecification,com.demo.user.common.client.MemberInfoClient,MemberRiskClient.FeignC lientSpecification,com.demo.user.common.client.MemberRiskClient,MemberWalletClient.FeignClientSpecification,com.demo.user.common.client.MemberWalletClient,memberWalletFlowCli ent.FeignClientSpecification,com.demo.user.common.client.MemberWalletFlowClient,riskEventClient.FeignClientSpecification,com.demo.user.common.client.RiskEventClient,userCenterMemberInfoClient.FeignClientSpecification,com.demo.user.common.client.UserCenterMemberInfoClient,userCenterOperatorClient.FeignClientSpecification,com.demo.user.common.client.UserCenterOperatorClient,captchaClient.FeignClientSpecification,com.demo.message.rest.CaptchaClient,channelIsolationClient.FeignClientSpecification,com.demo.message.rest.ChannelIsolationClient,channelPriorityClient.FeignClientSpecification,com.demo.message.rest.ChannelPriorityClient,complexMessageClient.FeignClientSpecification,com.demo.message.rest.ComplexMessageClient,jPushClient.FeignClientSpecification,com.demo.message.rest.JPushClient,messageFeishuBotClient.FeignClientSpecification,com.demo.message.rest.MessageFeishuBotClient,messageFeiShuBotClientV2.FeignClientSpecification,com.demo.message.rest.MessageFeiShuBotClientV2,stationLetterClient.FeignClientSpecification,com.demo.message.rest.StationLetterClient,idGenerateClient.FeignClientSpecification,com.demo.id.client.IdGenerateClient,couponClient.FeignClientSpecification,com.demo.marketing.client.coupon.CouponClient,couponManagerClient.FeignClientSpecification,com.demo.marketing.client.coupon.CouponManagerClient,couponMemberClient.FeignClientSpecification,com.demo.marketing.client.coupon.CouponMemberClient,normalFileClient.FeignClientSpecification,c], resourceLoader=null, customClassLoader=@Boolean[false], refreshed=@AtomicBoolean[true], MESSAGE_SOURCE_BEAN_NAME=@String[messageSource], LIFECYCLE_PROCESSOR_BEAN_NAME=@String[lifecycleProcessor], APPLICATION_EVENT_MULTICASTER_BEAN_NAME=@String[applicationEventMulticaster], logger=@SLF4JLocationAwareLog[org.apache.commons.logging.impl.SLF4JLocationAwareLog@71add15], id=@String[application-1], displayName=@String[org.springframework.boot.web.servlet.context.AnnotationConfigServletWebServerApplicationContext@58740366], parent=@AnnotationConfigApplicationContext[org.springframework.context.annotation.AnnotationConfigApplicationContext@62d363ab, started on Tue Aug 03 15:13:22 CST 2021], environment=@StandardServletEnvironment[StandardServletEnvironment {activeProfiles=[local, common-local, common], defaultProfiles=[default], propertySources=[MapPropertySource {name='server.ports'}, ConfigurationPropertySourcesPropertySource {name='configurationProperties'}, EncryptablePropertySourceWrapper {name='servletConfigInitParams'}, EncryptablePropertySourceWrapper {name='servletContextInitParams'}, EncryptableMapPropertySourceWrapper {name='systemProperties'}, EncryptableSystemEnvironmentPropertySourceWrapper{name='systemEnvironment'}, EncryptablePropertySourceWrapper {name='random'}, EncryptableMapPropertySourceWrapper {name='springCloudClientHostInfo'}, EncryptableMapPropertySourceWrapper {name='applicationConfig: [classpath:/application-common.yml]'}, EncryptableMapPropertySourceWrapper {name='applicationConfig: [classpath:/application-common-local.yml]'}, EncryptableMapPropertySourceWrapper {name='applicationConfig: [classpath:/application-local.yml]'}, EncryptableMapPropertySourceWrapper {name='applicationConfig: [classpath:/application.yml]'}, EncryptableMapPropertySourceWrapper {name='springCloudDefaultProperties'}, EncryptablePropertySourceWrapper {name='cachedrandom'}, {name='Management Server'}]}], beanFactoryPostProcessors=@ArrayList[isEmpty=false;size=5], startupDate=@Long[1627974802713], active=@AtomicBoolean[true], closed=@AtomicBoolean[false], startupShutdownMonitor=@Object[java.lang.Object@553a67da], shutdownHook=@[Thread[SpringContextShutdownHook,5,main]], resourcePatternResolver=@ServletContextResourcePatternResolver[org.springframework.web.context.support.ServletContextResourcePatternResolver@499ea1d], lifecycleProcessor=@DefaultLifecycleProcessor[org.springframework.context.support.DefaultLifecycleProcessor@61ac01da], messageSource=@DelegatingMessageSource[Empty MessageSource], applicationEventMulticaster=@SimpleApplicationEventMulticaster[org.springframework.context.event.SimpleApplicationEventMulticaster@ee42df5], applicationListeners=@LinkedHashSet[isEmpty=false;size=38], earlyApplicationListeners=@LinkedHashSet[isEmpty=false;size=19], earlyApplicationEvents=null, classLoader=@AppClassLoader[jdk.internal.loader.ClassLoaders$AppClassLoader@9e89d68], protocolResolvers=@LinkedHashSet[isEmpty=true;size=0], resourceCaches=@ConcurrentHashMap[isEmpty=true;size=0], ] Affect(row-cnt:1) cost in 4 ms.
利用 tt 命令通过 1000 这个 index 我们已经可以得到 spring context 了，得到后就可以利用 spring context 进行各种操作了。比如我们 get 一个 controller 的 bean 并执行一下方法
tt -i 1000 -w 'target.getApplicationContext().getBean("mealManagerController").listMealByCategoryId(1379999659854008320L)'
查看SQL语句
watch Connection
watch java.sql.Connection prepareStatement '{params,throwExp}' -n 5 -x 3
watch BoundSql (mybatis)
watch org.apache.ibatis.mapping.BoundSql getSql '{params,returnObj,throwExp}' -n 5 -x 3
热修复三板斧（生产慎用！）
反编译输出 .java 源码
jad --source-only com.demo.meal.pc.MealManagerController > /tmp/MealManagerController.java
修改代码
利用 vim 直接修改上面反编译出的文件内容
编译
搜索到对应类的classloader
[arthas@38341]$ sc -d *MealManagerController |grep classLoader classLoaderHash 9e89d68
mc(Memory Compiler) 命令来编译
mc -c 9e89d68 /tmp/MealManagerController.java -d /tmp
热加载
重新热加载(无需重启服务), 并且非侵入, 只是临时修改
[arthas@38341]$ redefine /tmp/com/demo/meal/pc/MealManagerController.class redefine success, size: 1, classes: com.demo.meal.pc.MealManagerController
限制
- redefine的class不能修改、添加、删除类的field和method，包括方法参数、方法名称及返回值
- redefine命令和jad/watch/trace/monitor/tt等命令会冲突。执行完redefine之后，如果再执行上面提到的命令，则会把redefine的字节码重置。
