尝试在 IntelliJ 2017.2.2 中的 Java 9 预发布下运行 Vaadin 8.1 应用程序 我能够使用一个新项目构建一个vaadinjavanine.war并使用 Jetty Server 托管相同的项目。
我最终尝试将生成的战争部署到雄猫服务器。但是，在tomcat服务器启动期间，我收到以下异常：
21-Aug-2017 22:53:38.830 SEVERE [localhost-startStop-1] org.apache.catalina.startup.ContextConfig.processAnnotationsFile Unable to process file [/Library/Tomcat/apache-tomcat-8.0.22/webapps/vaadinjavanine/WEB-INF/classes/module-info.class] for annotations
org.apache.tomcat.util.bcel.classfile.ClassFormatException: Invalid byte tag in constant pool: 19
at org.apache.tomcat.util.bcel.classfile.Constant.readConstant(Constant.java:97)
at org.apache.tomcat.util.bcel.classfile.ConstantPool.<init>(ConstantPool.java:55)
at org.apache.tomcat.util.bcel.classfile.ClassParser.readConstantPool(ClassParser.java:177)
at org.apache.tomcat.util.bcel.classfile.ClassParser.parse(ClassParser.java:85)
at org.apache.catalina.startup.ContextConfig.processAnnotationsStream(ContextConfig.java:2011)
at org.apache.catalina.startup.ContextConfig.processAnnotationsFile(ContextConfig.java:1994)
at org.apache.catalina.startup.ContextConfig.processAnnotationsFile(ContextConfig.java:1988)
at org.apache.catalina.startup.ContextConfig.processAnnotationsUrl(ContextConfig.java:1939)
at org.apache.catalina.startup.ContextConfig.processAnnotations(ContextConfig.java:1897)
at org.apache.catalina.startup.ContextConfig.webConfig(ContextConfig.java:1149)
at org.apache.catalina.startup.ContextConfig.configureStart(ContextConfig.java:771)
at org.apache.catalina.startup.ContextConfig.lifecycleEvent(ContextConfig.java:305)
at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:117)
at org.apache.catalina.util.LifecycleBase.fireLifecycleEvent(LifecycleBase.java:90)
at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5066)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:725)
at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:701)
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:717)
at org.apache.catalina.startup.HostConfig.deployWAR(HostConfig.java:945)
at org.apache.catalina.startup.HostConfig$DeployWar.run(HostConfig.java:1768)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
21-Aug-2017 22:53:38.980 SEVERE [localhost-startStop-1] org.apache.catalina.core.ContainerBase.addChildInternal ContainerBase.addChild: start:
org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Catalina].StandardHost[localhost].StandardContext[/vaadinjavanine]]
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:154)
at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:725)
at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:701)
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:717)
at org.apache.catalina.startup.HostConfig.deployWAR(HostConfig.java:945)
at org.apache.catalina.startup.HostConfig$DeployWar.run(HostConfig.java:1768)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.UnsupportedClassVersionError: nullpointer/MyUI$MyUIServlet has been compiled by a more recent version of the Java Runtime (class file version 53.0), this version of the Java Runtime only recognizes class file versions up to 52.0 (unable to load class nullpointer.MyUI$MyUIServlet)
at org.apache.catalina.loader.WebappClassLoaderBase.findClassInternal(WebappClassLoaderBase.java:2476)
at org.apache.catalina.loader.WebappClassLoaderBase.findClass(WebappClassLoaderBase.java:854)
at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1274)
at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1157)
at org.atmosphere.util.IOUtils.isAtmosphere(IOUtils.java:381)
at org.atmosphere.cpr.ContainerInitializer.onStartup(ContainerInitializer.java:58)
at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5156)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
... 10 more
21-Aug-2017 22:53:38.981 SEVERE [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployWAR Error deploying web application archive /Library/Tomcat/apache-tomcat-8.0.22/webapps/vaadinjavanine.war
java.lang.IllegalStateException: ContainerBase.addChild: start: org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Catalina].StandardHost[localhost].StandardContext[/vaadinjavanine]]
at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:728)
at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:701)
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:717)
at org.apache.catalina.startup.HostConfig.deployWAR(HostConfig.java:945)
at org.apache.catalina.startup.HostConfig$DeployWar.run(HostConfig.java:1768)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
异常状态无法处理从Java9module-info.java生成的module-info.class。有没有办法解决这个问题？或者这实际上意味着tomcat还没有为java9模块做好准备？
注意：作为Tomcat的新手，我没有自定义任何设置。如果可以共享其他内容以获取更多信息，请告诉我。
我不是 Tomcat 专家，但看起来模块描述符不是最严重的问题。下一个异常包含以下块：
原因：
java.lang.UnsupportedClassVersionError：nullpointer/MyUI$MyUIServlet已由较新版本的 Java 运行时(类文件版本 53.0(编译，此版本的 Java 运行时仅识别最高 52.0 的类文件版本(无法加载类nullpointer.MyUI$MyUIServlet(
这使得你看起来像是在Java 8(类文件版本52(上运行Tomcat，而你的代码是用Java 9(类文件版本53(编译的。
确保在Java 9上运行Tomcat。此外，您可能想尝试Tomcat 9的早期访问版本，这是Java 9兼容性所必需的。