Spring Cloud Data Flow 2.9.6部署Java 17应用失败求助

当前使用Spring Cloud Data Flow 2.9.6版本，此前所有应用均基于Java 8部署在Pivotal Cloud Foundry环境中。目前正进行版本迁移，已将部分应用升级至Java 17和21，并通过以下两项配置尝试部署流：

• 在流定义中添加配置：

  --JBP_CONFIG_OPEN_JDK_JRE='{jre: { version: 17.+ }}'
  

• 为应用添加部署器属性：

  deployer.appname.cloudfoundry.use-spring-application-json: false
  

部署未成功，Skipper日志中出现如下错误：

Exception in thread "skipperStateMachineTaskExecutor-4" java.lang.UnsupportedClassVersionError: io/pivotal/cfenv/core/CfEnv has been compiled by a more recent version of the Java Runtime (class file version 61.0), this version of the Java Runtime only recognizes class file versions up to 52.0
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:756)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
at java.net.URLClassLoader.defineClass(URLClassLoader.java:473)
at java.net.URLClassLoader.access$100(URLClassLoader.java:74)
at java.net.URLClassLoader$1.run(URLClassLoader.java:369)
at java.net.URLClassLoader$1.run(URLClassLoader.java:363)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:362)
at java.lang.ClassLoader.loadClass(ClassLoader.java:418)
at java.lang.ClassLoader.loadClass(ClassLoader.java:351)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:348)
at org.springframework.cloud.deployer.spi.cloudfoundry.CfEnvAwareResource$CfEnvResolver.hasCfEnv(CfEnvAwareResource.java:145)
at org.springframework.cloud.deployer.spi.cloudfoundry.CfEnvAwareResource.(CfEnvAwareResource.java:53)
at org.springframework.cloud.deployer.spi.cloudfoundry.CfEnvAwareResource.of(CfEnvAwareResource.java:49)
at org.springframework.cloud.deployer.spi.cloudfoundry.CfEnvAwareAppDeploymentRequest.(CfEnvAwareAppDeploymentRequest.java:35)
at org.springframework.cloud.deployer.spi.cloudfoundry.CfEnvAwareAppDeploymentRequest.of(CfEnvAwareAppDeploymentRequest.java:30)
at org.springframework.cloud.deployer.spi.cloudfoundry.CloudFoundryAppDeployer.deploy(CloudFoundryAppDeployer.java:98)
at org.springframework.cloud.skipper.server.deployer.DefaultReleaseManager.install(DefaultReleaseManager.java:142)
at org.springframework.cloud.skipper.server.service.ReleaseService.install(ReleaseService.java:198)
at org.springframework.cloud.skipper.server.service.ReleaseService.install(ReleaseService.java:184)
at org.springframework.cloud.skipper.server.service.ReleaseService.install(ReleaseService.java:145)
at org.springframework.cloud.skipper.server.service.ReleaseService$$FastClassBySpringCGLIB$$f1c5f0a2.invoke()
at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:218)
at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:793)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:163)
at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:763)
at org.springframework.transaction.interceptor.TransactionInterceptor$1.proceedWithInvocation(TransactionInterceptor.java:123)
at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:388)
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:119)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186)
at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:763)
at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:708)
at org.springframework.cloud.skipper.server.service.ReleaseService$$EnhancerBySpringCGLIB$$1c3625ff.install()
at org.springframework.cloud.skipper.server.statemachine.InstallInstallAction.executeInternal(InstallInstallAction.java:69)
at org.springframework.cloud.skipper.server.statemachine.AbstractAction.execute(AbstractAction.java:41)
at org.springframework.statemachine.state.AbstractState.executeAction(AbstractState.java:496)
at org.springframework.statemachine.state.ObjectState.entry(ObjectState.java:158)
at org.springframework.statemachine.support.AbstractStateMachine.entryToState(AbstractStateMachine.java:1322)
at org.springframework.statemachine.support.AbstractStateMachine.entryToState(AbstractStateMachine.java:1263)
at org.springframework.statemachine.support.AbstractStateMachine.setCurrentStateInternal(AbstractStateMachine.java:1059)
at org.springframework.statemachine.support.AbstractStateMachine.setCurrentState(AbstractStateMachine.java:1033)
at org.springframework.statemachine.support.AbstractStateMachine.switchToState(AbstractStateMachine.java:926)
at org.springframework.statemachine.support.AbstractStateMachine.access$500(AbstractStateMachine.java:82)
at org.springframework.statemachine.support.AbstractStateMachine$3.transit(AbstractStateMachine.java:334)
at org.springframework.statemachine.support.DefaultStateMachineExecutor.handleInitialTrans(DefaultStateMachineExecutor.java:302)
at org.springframework.statemachine.support.DefaultStateMachineExecutor.processTriggerQueue(DefaultStateMachineExecutor.java:398)
at org.springframework.statemachine.support.DefaultStateMachineExecutor.access$200(DefaultStateMachineExecutor.java:64)
at org.springframework.statemachine.support.DefaultStateMachineExecutor$1.run(DefaultStateMachineExecutor.java:330)
at org.springframework.core.task.SyncTaskExecutor.execute(SyncTaskExecutor.java:50)
at org.springframework.statemachine.support.DefaultStateMachineExecutor.scheduleEventQueueProcessing(DefaultStateMachineExecutor.java:353)
at org.springframework.statemachine.support.DefaultStateMachineExecutor.execute(DefaultStateMachineExecutor.java:162)
at org.springframework.statemachine.support.DefaultStateMachineExecutor.doStart(DefaultStateMachineExecutor.java:174)
at org.springframework.statemachine.support.LifecycleObjectSupport.start(LifecycleObjectSupport.java:120)
at org.springframework.statemachine.support.AbstractStateMachine.doStart(AbstractStateMachine.java:418)
at org.springframework.statemachine.support.LifecycleObjectSupport.start(LifecycleObjectSupport.java:120)
at org.springframework.statemachine.state.StateMachineState.entry(StateMachineState.java:236)
at org.springframework.statemachine.support.AbstractStateMachine.entryToState(AbstractStateMachine.java:1322)
at org.springframework.statemachine.support.AbstractStateMachine.entryToState(AbstractStateMachine.java:1263)
at org.springframework.statemachine.support.AbstractStateMachine.setCurrentStateInternal(AbstractStateMachine.java:1059)
at org.springframework.statemachine.support.AbstractStateMachine.setCurrentState(AbstractStateMachine.java:1033)
at org.springframework.statemachine.support.AbstractStateMachine.switchToState(AbstractStateMachine.java:926)
at org.springframework.statemachine.support.AbstractStateMachine.access$500(AbstractStateMachine.java:82)
at org.springframework.statemachine.support.AbstractStateMachine$3.transit(AbstractStateMachine.java:337)
at org.springframework.statemachine.support.DefaultStateMachineExecutor.handleTriggerTrans(DefaultStateMachineExecutor.java:287)
at org.springframework.statemachine.support.DefaultStateMachineExecutor.handleTriggerTrans(DefaultStateMachineExecutor.java:210)
at org.springframework.statemachine.support.DefaultStateMachineExecutor.processTriggerQueue(DefaultStateMachineExecutor.java:450)
at org.springframework.statemachine.support.DefaultStateMachineExecutor.access$200(DefaultStateMachineExecutor.java:64)
at org.springframework.statemachine.support.DefaultStateMachineExecutor$1.run(DefaultStateMachineExecutor.java:324)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at java.lang.Thread.run(Thread.java:750)

请问这是Spring Cloud Data Flow/Skipper Server版本限制导致的，还是需要调整其他属性才能解决？

这是Skipper Server运行环境的Java版本与依赖库不兼容导致的问题，和Spring Cloud Data Flow/Skipper的版本本身限制无关，核心原因是：

• Skipper Server自身运行在Java 8环境中，而它尝试加载的io.pivotal.cfenv.core.CfEnv类是用Java 17（class file version 61.0）编译的，Java 8仅支持最高52.0版本的类文件，因此抛出UnsupportedClassVersionError。

解决步骤 #

1. 升级Skipper Server的Java版本
   将Skipper Server的运行环境切换到Java 17（和目标应用版本一致）。Spring Cloud Data Flow 2.9.6官方支持Java 8/11/17，无需升级SCDF/Skipper版本，只需调整Skipper Server的部署JRE配置即可。这是最彻底、最推荐的解决方式。

2. 临时调整依赖版本（不推荐长期使用）
   如果暂时无法升级Skipper的Java版本，可以在Skipper的依赖管理中降低cfenv库的版本，确保其编译版本不超过Java 8。但这种方式可能引发其他兼容性问题，仅作为短期过渡方案。

3. 验证应用配置的作用范围
   确认流定义中的JBP_CONFIG_OPEN_JDK_JRE配置仅作用于目标应用实例，而非Skipper Server本身——该配置是指定应用使用的JRE版本，Skipper Server的JRE版本需要单独配置。

内容的提问来源于stack exchange，提问作者CuriousK