1.环境win10camunda7.17.0jdk11 idea 2022.2.3利用springboot项目重新构建camunda-engine用mysql5.7数据库。2.camunda数据库据说可以在启动引擎端spring boot项目的时候自动创建数据库此处是手动导入创建的。3.camunda引擎端https://camunda.com/download/https://camunda.com/download/修改后pom.xml内容如下project xmlnshttp://maven.apache.org/POM/4.0.0 xmlns:xsihttp://www.w3.org/2001/XMLSchema-instance xsi:schemaLocationhttp://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd modelVersion4.0.0/modelVersion parent groupIdorg.springframework.boot/groupId artifactIdspring-boot-starter-parent/artifactId version2.6.4/version /parent groupIdcom.forestlake.workflow/groupId artifactIdcamunda-engine/artifactId version1.0.0-SNAPSHOT/version properties project.build.sourceEncodingUTF-8/project.build.sourceEncoding maven.compiler.source11/maven.compiler.source maven.compiler.target11/maven.compiler.target /properties dependencyManagement dependencies dependency groupIdorg.springframework.boot/groupId artifactIdspring-boot-dependencies/artifactId version2.6.4/version typepom/type scopeimport/scope /dependency dependency groupIdorg.camunda.bpm/groupId artifactIdcamunda-bom/artifactId version7.17.0/version scopeimport/scope typepom/type /dependency /dependencies /dependencyManagement dependencies dependency groupIdorg.camunda.bpm.springboot/groupId artifactIdcamunda-bpm-spring-boot-starter-rest/artifactId /dependency dependency groupIdorg.camunda.bpm.springboot/groupId artifactIdcamunda-bpm-spring-boot-starter/artifactId version7.17.0/version /dependency dependency groupIdorg.camunda.bpm.springboot/groupId artifactIdcamunda-bpm-spring-boot-starter-webapp/artifactId /dependency dependency groupIdorg.camunda.bpm/groupId artifactIdcamunda-engine-plugin-spin/artifactId /dependency dependency groupIdorg.camunda.spin/groupId artifactIdcamunda-spin-dataformat-all/artifactId /dependency dependency groupIdmysql/groupId artifactIdmysql-connector-java/artifactId version8.0.30/version /dependency dependency groupIdorg.springframework.boot/groupId artifactIdspring-boot-starter-jdbc/artifactId /dependency !-- https://mvnrepository.com/artifact/org.codehaus.groovy/groovy-all -- dependency groupIdorg.codehaus.groovy/groupId artifactIdgroovy-all/artifactId version3.0.13/version typepom/type /dependency !--groovy发送Http请求底层是对HTTPClient封装 HttpBuilder-- dependency groupIdorg.codehaus.groovy.modules.http-builder/groupId artifactIdhttp-builder/artifactId version0.7.1/version /dependency dependency groupIdorg.camunda.bpm/groupId artifactIdcamunda-engine-plugin-connect/artifactId version7.17.0/version /dependency dependency groupIdorg.camunda.connect/groupId artifactIdcamunda-connect-connectors-all/artifactId version1.5.5/version /dependency /dependencies build plugins plugin groupIdorg.springframework.boot/groupId artifactIdspring-boot-maven-plugin/artifactId version2.6.4/version /plugin /plugins /build /projectapplication.yaml修改如下spring: datasource: url: jdbc:mysql://127.0.0.1:3306/camunda?useUnicodetruecharacterEncodingUTF-8autoReconnecttrueuseSSLfalsenullCatalogMeansCurrenttrue driver-class-name: com.mysql.cj.jdbc.Driver username: root password: rootcamunda引擎端启动正常4.spring boot 外部任务客户端根据官网文档创建外部任务客户端外部任务客户端 Spring Boot Starter | docs.camunda.orgCamunda流程平台中文站、中文文档http://camunda-cn.shaochenfeng.com/user-guide/ext-client/spring-boot-starter/将camunda版本改为7.17.0;pom.xml如下?xml version1.0 encodingUTF-8? project xmlnshttp://maven.apache.org/POM/4.0.0 xmlns:xsihttp://www.w3.org/2001/XMLSchema-instance xsi:schemaLocationhttp://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd modelVersion4.0.0/modelVersion groupIdcom.tjm/groupId artifactIdcamunda-external-task-java/artifactId version0.0.1-SNAPSHOT/version namecamunda-external-task-java/name descriptioncamunda外部任务/description properties java.version11/java.version project.build.sourceEncodingUTF-8/project.build.sourceEncoding project.reporting.outputEncodingUTF-8/project.reporting.outputEncoding maven.compiler.source8/maven.compiler.source maven.compiler.target8/maven.compiler.target /properties dependencyManagement dependencies dependency groupIdorg.springframework.boot/groupId artifactIdspring-boot-dependencies/artifactId version2.6.4/version typepom/type scopeimport/scope /dependency /dependencies /dependencyManagement dependencies dependency groupIdorg.camunda.bpm.springboot/groupId artifactIdcamunda-bpm-spring-boot-starter-external-task-client/artifactId version7.17.0/version /dependency dependency groupIdorg.springframework.boot/groupId artifactIdspring-boot-starter-web/artifactId /dependency dependency groupIdorg.springframework.boot/groupId artifactIdspring-boot-starter/artifactId /dependency /dependencies build plugins plugin groupIdorg.springframework.boot/groupId artifactIdspring-boot-maven-plugin/artifactId version2.6.4/version /plugin /plugins /build /projectapplication.properties如下server.port8083 spring.application.nameexternal-task camunda.bpm.client.base-urlhttp://localhost:8080/engine-rest camunda.bpm.client.async-response-timeout20000 camunda.bpm.client.max-tasks50 camunda.bpm.client.lock-duration10000 camunda.bpm.client.worker-idjava-client外部任务订阅类如下package com.tjm.externaltask; import org.camunda.bpm.client.spring.annotation.ExternalTaskSubscription; import org.camunda.bpm.client.task.ExternalTaskHandler; import org.springframework.context.annotation.Bean; import org.springframework.context.annotation.Configuration; /** * description: 外部任务订阅主题 * author: tjm * date: 2022/11/8 10:03 * param: * return: **/ Configuration public class ShoppingService { /** * description: 物流发货 * author: tjm * date: 2022/11/8 10:08 * param: [] * return: org.camunda.bpm.client.task.ExternalTaskHandler **/ Bean ExternalTaskSubscription(topicName deliver_goods, processDefinitionKeyIn {Process_shopping}, lockDuration 50000) public ExternalTaskHandler deliverGoods() { return (externalTask, externalTaskService) - { System.out.println(商家已经发货); externalTaskService.complete(externalTask); }; } /** * description: 收货 * author: tjm * date: 2022/11/8 10:08 * param: [] * return: org.camunda.bpm.client.task.ExternalTaskHandler **/ Bean ExternalTaskSubscription(topicName receive_goods) public ExternalTaskHandler receiveGoods() { return (externalTask, externalTaskService) - { System.out.println(顾客收到物品); externalTaskService.complete(externalTask); }; } }启动类入口5.camunda modler设计流程bpmn文件6.外部任务客户端spring boot项目启动失败D:\Program Files\Java\jdk-11.0.6\bin\java.exe -javaagent:D:\Program Files\JetBrains\IntelliJ IDEA Community Edition 2022.2.3\lib\idea_rt.jar57595:D:\Program Files\JetBrains\IntelliJ IDEA Community Edition 2022.2.3\bin -Dfile.encodingUTF-8 -classpath D:\TJM-SpringCloud-WorkSpace\camunda实战课程源码--【2022-11-1】\camunda-external-task-java-error\target\classes;D:\localRepository\org\camunda\bpm\springboot\camunda-bpm-spring-boot-starter-external-task-client\7.17.0\camunda-bpm-spring-boot-starter-external-task-client-7.17.0.jar;D:\localRepository\org\camunda\bpm\camunda-external-task-client-spring\7.17.0\camunda-external-task-client-spring-7.17.0.jar;D:\localRepository\org\camunda\bpm\camunda-external-task-client\7.17.0\camunda-external-task-client-7.17.0.jar;D:\localRepository\org\camunda\commons\camunda-commons-logging\1.10.0\camunda-commons-logging-1.10.0.jar;D:\localRepository\org\camunda\commons\camunda-commons-typed-values\7.17.0\camunda-commons-typed-values-7.17.0.jar;D:\localRepository\org\camunda\commons\camunda-commons-utils\1.10.0\camunda-commons-utils-1.10.0.jar;D:\localRepository\org\apache\httpcomponents\httpclient\4.5.13\httpclient-4.5.13.jar;D:\localRepository\org\apache\httpcomponents\httpcore\4.4.15\httpcore-4.4.15.jar;D:\localRepository\commons-codec\commons-codec\1.15\commons-codec-1.15.jar;D:\localRepository\org\springframework\boot\spring-boot-autoconfigure\2.6.4\spring-boot-autoconfigure-2.6.4.jar;D:\localRepository\org\springframework\boot\spring-boot-starter-web\2.6.4\spring-boot-starter-web-2.6.4.jar;D:\localRepository\org\springframework\boot\spring-boot-starter-json\2.6.4\spring-boot-starter-json-2.6.4.jar;D:\localRepository\com\fasterxml\jackson\core\jackson-databind\2.13.1\jackson-databind-2.13.1.jar;D:\localRepository\com\fasterxml\jackson\core\jackson-annotations\2.13.1\jackson-annotations-2.13.1.jar;D:\localRepository\com\fasterxml\jackson\core\jackson-core\2.13.1\jackson-core-2.13.1.jar;D:\localRepository\com\fasterxml\jackson\datatype\jackson-datatype-jdk8\2.13.1\jackson-datatype-jdk8-2.13.1.jar;D:\localRepository\com\fasterxml\jackson\datatype\jackson-datatype-jsr310\2.13.1\jackson-datatype-jsr310-2.13.1.jar;D:\localRepository\com\fasterxml\jackson\module\jackson-module-parameter-names\2.13.1\jackson-module-parameter-names-2.13.1.jar;D:\localRepository\org\springframework\boot\spring-boot-starter-tomcat\2.6.4\spring-boot-starter-tomcat-2.6.4.jar;D:\localRepository\org\apache\tomcat\embed\tomcat-embed-core\9.0.58\tomcat-embed-core-9.0.58.jar;D:\localRepository\org\apache\tomcat\embed\tomcat-embed-el\9.0.58\tomcat-embed-el-9.0.58.jar;D:\localRepository\org\apache\tomcat\embed\tomcat-embed-websocket\9.0.58\tomcat-embed-websocket-9.0.58.jar;D:\localRepository\org\springframework\spring-web\5.3.16\spring-web-5.3.16.jar;D:\localRepository\org\springframework\spring-beans\5.3.16\spring-beans-5.3.16.jar;D:\localRepository\org\springframework\spring-webmvc\5.3.16\spring-webmvc-5.3.16.jar;D:\localRepository\org\springframework\spring-aop\5.3.16\spring-aop-5.3.16.jar;D:\localRepository\org\springframework\spring-context\5.3.16\spring-context-5.3.16.jar;D:\localRepository\org\springframework\spring-expression\5.3.16\spring-expression-5.3.16.jar;D:\localRepository\org\springframework\boot\spring-boot-starter\2.6.4\spring-boot-starter-2.6.4.jar;D:\localRepository\org\springframework\boot\spring-boot\2.6.4\spring-boot-2.6.4.jar;D:\localRepository\org\springframework\boot\spring-boot-starter-logging\2.6.4\spring-boot-starter-logging-2.6.4.jar;D:\localRepository\ch\qos\logback\logback-classic\1.2.10\logback-classic-1.2.10.jar;D:\localRepository\ch\qos\logback\logback-core\1.2.10\logback-core-1.2.10.jar;D:\localRepository\org\slf4j\slf4j-api\1.7.36\slf4j-api-1.7.36.jar;D:\localRepository\org\apache\logging\log4j\log4j-to-slf4j\2.17.1\log4j-to-slf4j-2.17.1.jar;D:\localRepository\org\apache\logging\log4j\log4j-api\2.17.1\log4j-api-2.17.1.jar;D:\localRepository\org\slf4j\jul-to-slf4j\1.7.36\jul-to-slf4j-1.7.36.jar;D:\localRepository\jakarta\annotation\jakarta.annotation-api\1.3.5\jakarta.annotation-api-1.3.5.jar;D:\localRepository\org\springframework\spring-core\5.3.16\spring-core-5.3.16.jar;D:\localRepository\org\springframework\spring-jcl\5.3.16\spring-jcl-5.3.16.jar;D:\localRepository\org\yaml\snakeyaml\1.29\snakeyaml-1.29.jar com.tjm.ExternalTaskApplication ____ _ ____ _ _ __ / ___| __ _ _ __ ___ _ _ _ __ __| | __ _ | _ \ | | __ _ | |_ / _| ___ _ __ _ __ ___ | | / _ | | _ _ \ | | | | | _ \ / _ | / _ | | |_) | | | / _ | | __| | |_ / _ \ | __| | _ _ \ | |___ | (_| | | | | | | | | |_| | | | | | | (_| | | (_| | | __/ | | | (_| | | |_ | _| | (_) | | | | | | | | | \____| \__,_| |_| |_| |_| \__,_| |_| |_| \__,_| \__,_| |_| |_| \__,_| \__| |_| \___/ |_| |_| |_| |_| _____ _ _ _____ _ ____ _ _ _ | ____| __ __ | |_ ___ _ __ _ __ __ _ | | |_ _| __ _ ___ | | __ / ___| | | (_) ___ _ __ | |_ | _| \ \/ / | __| / _ \ | __| | _ \ / _ | | | | | / _ | / __| | |/ / | | | | | | / _ \ | _ \ | __| | |___ | |_ | __/ | | | | | | | (_| | | | | | | (_| | \__ \ | | |___ | | | | | __/ | | | | | |_ |_____| /_/\_\ \__| \___| |_| |_| |_| \__,_| |_| |_| \__,_| |___/ |_|\_\ \____| |_| |_| \___| |_| |_| \__| Spring-Boot: (v2.6.4) Camunda Platform: (v7.17.0) 2022-11-08 10:29:23.271 INFO 1800 --- [ main] com.tjm.ExternalTaskApplication : Starting ExternalTaskApplication using Java 11.0.6 on tjm-12426 with PID 1800 (D:\TJM-SpringCloud-WorkSpace\camunda实战课程源码--【2022-11-1】\camunda-external-task-java-error\target\classes started by DELL in D:\TJM-SpringCloud-WorkSpace\camunda实战课程源码--【2022-11-1】\camunda-external-task-java-error) 2022-11-08 10:29:23.275 INFO 1800 --- [ main] com.tjm.ExternalTaskApplication : No active profile set, falling back to 1 default profile: default 2022-11-08 10:29:24.428 INFO 1800 --- [ main] o.s.b.w.embedded.tomcat.TomcatWebServer : Tomcat initialized with port(s): 8083 (http) 2022-11-08 10:29:24.439 INFO 1800 --- [ main] o.apache.catalina.core.StandardService : Starting service [Tomcat] 2022-11-08 10:29:24.439 INFO 1800 --- [ main] org.apache.catalina.core.StandardEngine : Starting Servlet engine: [Apache Tomcat/9.0.58] 2022-11-08 10:29:24.528 INFO 1800 --- [ main] o.a.c.c.C.[Tomcat].[localhost].[/] : Initializing Spring embedded WebApplicationContext 2022-11-08 10:29:24.528 INFO 1800 --- [ main] w.s.c.ServletWebServerApplicationContext : Root WebApplicationContext: initialization completed in 1192 ms 2022-11-08 10:29:24.992 INFO 1800 --- [ main] org.camunda.bpm.client : TASK/CLIENT-01026 Discovered data format provider: org.camunda.bpm.client.variable.impl.format.json.JacksonJsonDataFormatProvider[name application/json] 2022-11-08 10:29:24.994 INFO 1800 --- [ main] org.camunda.bpm.client : TASK/CLIENT-01025 Discovered data format: org.camunda.bpm.client.variable.impl.format.json.JacksonJsonDataFormat[name application/json] 2022-11-08 10:29:24.995 INFO 1800 --- [ main] org.camunda.bpm.client : TASK/CLIENT-01026 Discovered data format provider: org.camunda.bpm.client.variable.impl.format.serializable.SerializableDataFormatProvider[name application/x-java-serialized-object] 2022-11-08 10:29:24.995 INFO 1800 --- [ main] org.camunda.bpm.client : TASK/CLIENT-01025 Discovered data format: org.camunda.bpm.client.variable.impl.format.serializable.SerializableDataFormat[name application/x-java-serialized-object] 2022-11-08 10:29:24.995 INFO 1800 --- [ main] org.camunda.bpm.client : TASK/CLIENT-01026 Discovered data format provider: org.camunda.bpm.client.variable.impl.format.xml.DomXmlDataFormatProvider[name application/xml] 2022-11-08 10:29:24.996 WARN 1800 --- [ main] ConfigServletWebServerApplicationContext : Exception encountered during context initialization - cancelling refresh attempt: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name deliverGoodsSubscription: Unsatisfied dependency expressed through field client; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name externalTaskClient: FactoryBean threw exception on object creation; nested exception is java.lang.NoClassDefFoundError: javax/xml/bind/JAXBException 2022-11-08 10:29:24.999 INFO 1800 --- [ main] o.apache.catalina.core.StandardService : Stopping service [Tomcat] 2022-11-08 10:29:25.010 INFO 1800 --- [ main] ConditionEvaluationReportLoggingListener : Error starting ApplicationContext. To display the conditions report re-run your application with debug enabled. 2022-11-08 10:29:25.027 ERROR 1800 --- [ main] o.s.boot.SpringApplication : Application run failed org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name deliverGoodsSubscription: Unsatisfied dependency expressed through field client; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name externalTaskClient: FactoryBean threw exception on object creation; nested exception is java.lang.NoClassDefFoundError: javax/xml/bind/JAXBException at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.resolveFieldValue(AutowiredAnnotationBeanPostProcessor.java:659) ~[spring-beans-5.3.16.jar:5.3.16] at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:639) ~[spring-beans-5.3.16.jar:5.3.16] at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:119) ~[spring-beans-5.3.16.jar:5.3.16] at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessProperties(AutowiredAnnotationBeanPostProcessor.java:399) ~[spring-beans-5.3.16.jar:5.3.16] at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1431) ~[spring-beans-5.3.16.jar:5.3.16] at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:619) ~[spring-beans-5.3.16.jar:5.3.16] at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:542) ~[spring-beans-5.3.16.jar:5.3.16] at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:335) ~[spring-beans-5.3.16.jar:5.3.16] at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:234) ~[spring-beans-5.3.16.jar:5.3.16] at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:333) ~[spring-beans-5.3.16.jar:5.3.16] at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:208) ~[spring-beans-5.3.16.jar:5.3.16] at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:953) ~[spring-beans-5.3.16.jar:5.3.16] at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:918) ~[spring-context-5.3.16.jar:5.3.16] at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:583) ~[spring-context-5.3.16.jar:5.3.16] at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:145) ~[spring-boot-2.6.4.jar:2.6.4] at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:740) ~[spring-boot-2.6.4.jar:2.6.4] at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:415) ~[spring-boot-2.6.4.jar:2.6.4] at org.springframework.boot.SpringApplication.run(SpringApplication.java:303) ~[spring-boot-2.6.4.jar:2.6.4] at org.springframework.boot.SpringApplication.run(SpringApplication.java:1312) ~[spring-boot-2.6.4.jar:2.6.4] at org.springframework.boot.SpringApplication.run(SpringApplication.java:1301) ~[spring-boot-2.6.4.jar:2.6.4] at com.tjm.ExternalTaskApplication.main(ExternalTaskApplication.java:17) ~[classes/:na] Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name externalTaskClient: FactoryBean threw exception on object creation; nested exception is java.lang.NoClassDefFoundError: javax/xml/bind/JAXBException at org.springframework.beans.factory.support.FactoryBeanRegistrySupport.doGetObjectFromFactoryBean(FactoryBeanRegistrySupport.java:176) ~[spring-beans-5.3.16.jar:5.3.16] at org.springframework.beans.factory.support.FactoryBeanRegistrySupport.getObjectFromFactoryBean(FactoryBeanRegistrySupport.java:101) ~[spring-beans-5.3.16.jar:5.3.16] at org.springframework.beans.factory.support.AbstractBeanFactory.getObjectForBeanInstance(AbstractBeanFactory.java:1884) ~[spring-beans-5.3.16.jar:5.3.16] at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.getObjectForBeanInstance(AbstractAutowireCapableBeanFactory.java:1284) ~[spring-beans-5.3.16.jar:5.3.16] at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:345) ~[spring-beans-5.3.16.jar:5.3.16] at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:208) ~[spring-beans-5.3.16.jar:5.3.16] at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:276) ~[spring-beans-5.3.16.jar:5.3.16] at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1389) ~[spring-beans-5.3.16.jar:5.3.16] at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1309) ~[spring-beans-5.3.16.jar:5.3.16] at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.resolveFieldValue(AutowiredAnnotationBeanPostProcessor.java:656) ~[spring-beans-5.3.16.jar:5.3.16] ... 20 common frames omitted Caused by: java.lang.NoClassDefFoundError: javax/xml/bind/JAXBException at org.camunda.bpm.client.variable.impl.format.xml.DomXmlDataFormatProvider.createInstance(DomXmlDataFormatProvider.java:31) ~[camunda-external-task-client-7.17.0.jar:7.17.0] at org.camunda.bpm.client.impl.ExternalTaskClientBuilderImpl.lookupProvider(ExternalTaskClientBuilderImpl.java:306) ~[camunda-external-task-client-7.17.0.jar:7.17.0] at org.camunda.bpm.client.impl.ExternalTaskClientBuilderImpl.lookupCustomDataFormats(ExternalTaskClientBuilderImpl.java:297) ~[camunda-external-task-client-7.17.0.jar:7.17.0] at org.camunda.bpm.client.impl.ExternalTaskClientBuilderImpl.lookupDataFormats(ExternalTaskClientBuilderImpl.java:285) ~[camunda-external-task-client-7.17.0.jar:7.17.0] at org.camunda.bpm.client.impl.ExternalTaskClientBuilderImpl.initVariableMappers(ExternalTaskClientBuilderImpl.java:247) ~[camunda-external-task-client-7.17.0.jar:7.17.0] at org.camunda.bpm.client.impl.ExternalTaskClientBuilderImpl.build(ExternalTaskClientBuilderImpl.java:185) ~[camunda-external-task-client-7.17.0.jar:7.17.0] at org.camunda.bpm.client.spring.impl.client.ClientFactory.getObject(ClientFactory.java:92) ~[camunda-external-task-client-spring-7.17.0.jar:7.17.0] at org.camunda.bpm.client.spring.impl.client.ClientFactory.getObject(ClientFactory.java:36) ~[camunda-external-task-client-spring-7.17.0.jar:7.17.0] at org.springframework.beans.factory.support.FactoryBeanRegistrySupport.doGetObjectFromFactoryBean(FactoryBeanRegistrySupport.java:169) ~[spring-beans-5.3.16.jar:5.3.16] ... 29 common frames omitted Caused by: java.lang.ClassNotFoundException: javax.xml.bind.JAXBException at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:581) ~[na:na] at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178) ~[na:na] at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521) ~[na:na] ... 38 common frames omitted Process finished with exit code 17.问题分析及解决方法核心错误信息如下处理问题思路如下1.根据控制台错误提示信息应该是名称为deliverGoodsSubscription的bean创建失败于是全项目搜索deliverGoodsSubscription并没有发现有该bean名称的声明或者定义2.又在camunda-engine引擎端全文检索deliverGoodsSubscription也未发现有该bean名称3.又清理了camunda数据库重新导入脚本4.又换jdk85.又换spring boot 版本6.又更换项目路径不放到中文路径下面。一一尝试后问题依然没解决仍然提示deliverGoodsSubscription的bean创建失败问题肯定出在客户端了根据命名最接近的源头就是com.tjm.externaltask.ShoppingService#deliverGoods。于是继续查阅官方文档发现问题的根源如下说明是订阅任务的方法出了问题关注点回到了下面地方8.终极解决方法问题的根本原因是高版本的JDK中不包含javax.xml.bind相关包。解决方法加入低版本的依赖包。dependency groupIdjavax.xml.bind/groupId artifactIdjaxb-api/artifactId /dependency dependency groupIdcom.sun.xml.bind/groupId artifactIdjaxb-impl/artifactId version4.0.1/version /dependency dependency groupIdcom.sun.xml.bind/groupId artifactIdjaxb-core/artifactId version4.0.1/version /dependency客户端完整的pom.xml内容如下?xml version1.0 encodingUTF-8? project xmlnshttp://maven.apache.org/POM/4.0.0 xmlns:xsihttp://www.w3.org/2001/XMLSchema-instance xsi:schemaLocationhttp://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd modelVersion4.0.0/modelVersion groupIdcom.tjm/groupId artifactIdcamunda-external-task-java/artifactId version0.0.1-SNAPSHOT/version namecamunda-external-task-java/name descriptioncamunda外部任务/description properties java.version11/java.version project.build.sourceEncodingUTF-8/project.build.sourceEncoding project.reporting.outputEncodingUTF-8/project.reporting.outputEncoding maven.compiler.source8/maven.compiler.source maven.compiler.target8/maven.compiler.target /properties dependencyManagement dependencies dependency groupIdorg.springframework.boot/groupId artifactIdspring-boot-dependencies/artifactId version2.6.4/version typepom/type scopeimport/scope /dependency /dependencies /dependencyManagement dependencies dependency groupIdorg.camunda.bpm.springboot/groupId artifactIdcamunda-bpm-spring-boot-starter-external-task-client/artifactId version7.17.0/version /dependency dependency groupIdorg.springframework.boot/groupId artifactIdspring-boot-starter-web/artifactId /dependency dependency groupIdorg.springframework.boot/groupId artifactIdspring-boot-starter/artifactId /dependency dependency groupIdjavax.xml.bind/groupId artifactIdjaxb-api/artifactId /dependency dependency groupIdcom.sun.xml.bind/groupId artifactIdjaxb-impl/artifactId version4.0.1/version /dependency dependency groupIdcom.sun.xml.bind/groupId artifactIdjaxb-core/artifactId version4.0.1/version /dependency /dependencies build plugins plugin groupIdorg.springframework.boot/groupId artifactIdspring-boot-maven-plugin/artifactId version2.6.4/version /plugin /plugins /build /project客户端正常启动如下:9.测试如下;