jsf - 在没有 BV 的 Tomcat 8 上部署 OmniFaces 3.1 会抛出 java.lang.NoClassDefFoundError : javax/validation/ConstraintViolation

Question

我是第一次尝试安装 OmniFaces 3.1。将依赖项添加到我的 pom 文件后，启动 Tomcat 服务器时会出现 NoClassDefFoundError 。我尚未进行任何其他(web.xml、faces-config.xml)配置更改；仅添加了依赖项。

显然，发生异常的原因是在处理 Omnifaces 类注释期间出现 JSR303 依赖性。然而;在 OmniFaces 展示页面上我读到:

All OmniFaces versions have an optional dependency on JSR303 Bean Validation which is only required when you start to actually use o:validateBean or JsfLabelMessageInterpolator.

可选是关键字。

这是堆栈跟踪:

java.lang.NoClassDefFoundError: javax/validation/ConstraintViolation
    at java.lang.Class.getDeclaredMethods0(Native Method)
    at java.lang.Class.privateGetDeclaredMethods(Class.java:2701)
    at java.lang.Class.getDeclaredMethods(Class.java:1975)
    at com.sun.faces.util.Util.classHasAnnotations(Util.java:1145)
    at com.sun.faces.application.ApplicationInstanceFactoryMetadataMap.onPut(ApplicationInstanceFactoryMetadataMap.java:76)
    at com.sun.faces.application.ApplicationInstanceFactoryMetadataMap.onPut(ApplicationInstanceFactoryMetadataMap.java:43)
    at com.sun.faces.util.MetadataWrapperMap.put(MetadataWrapperMap.java:99)
    at com.sun.faces.config.processor.AbstractConfigProcessor.loadClass(AbstractConfigProcessor.java:425)
    at com.sun.faces.config.processor.FaceletTaglibConfigProcessor.processHandlerClass(FaceletTaglibConfigProcessor.java:446)
    at com.sun.faces.config.processor.FaceletTaglibConfigProcessor.processTags(FaceletTaglibConfigProcessor.java:393)
    at com.sun.faces.config.processor.FaceletTaglibConfigProcessor.processTagLibrary(FaceletTaglibConfigProcessor.java:327)
    at com.sun.faces.config.processor.FaceletTaglibConfigProcessor.process(FaceletTaglibConfigProcessor.java:271)
    at com.sun.faces.config.ConfigManager.initialize(ConfigManager.java:445)
    at com.sun.faces.config.ConfigureListener.contextInitialized(ConfigureListener.java:237)
    at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4577)
    at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5041)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183)
    at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1427)
    at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1417)
    at java.util.concurrent.FutureTask.run(FutureTask.java:266)
    at org.apache.tomcat.util.threads.InlineExecutorService.execute(InlineExecutorService.java:75)
    at java.util.concurrent.AbstractExecutorService.submit(AbstractExecutorService.java:134)
    at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:943)
    at org.apache.catalina.core.StandardHost.startInternal(StandardHost.java:839)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183)
    at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1427)
    at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1417)
    at java.util.concurrent.FutureTask.run(FutureTask.java:266)
    at org.apache.tomcat.util.threads.InlineExecutorService.execute(InlineExecutorService.java:75)
    at java.util.concurrent.AbstractExecutorService.submit(AbstractExecutorService.java:134)
    at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:943)
    at org.apache.catalina.core.StandardEngine.startInternal(StandardEngine.java:258)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183)
    at org.apache.catalina.core.StandardService.startInternal(StandardService.java:422)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183)
    at org.apache.catalina.core.StandardServer.startInternal(StandardServer.java:770)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183)
    at org.apache.catalina.startup.Catalina.start(Catalina.java:682)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:353)
    at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:493)
Caused by: java.lang.ClassNotFoundException: javax.validation.ConstraintViolation
    at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1275)
    at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1104)
    ... 44 more

Answer 1

这在 2.x 中有效，但实际上从 3.0 开始就出现了问题。

根本问题是，从 JSF 2.3 开始，JSF 2.3 兼容库中的标记处理程序也会在 web 应用启动期间扫描注释。这将隐式加载<o:validateBean>后面的标记处理程序类。即使它没有在网络应用程序中的任何地方使用。

我按照issue 467通过将 bean 验证操作重构到静态上下文中，修复了 3.2-SNAPSHOT 的问题，以便在加载标记处理程序类时不会加载它。