jsf - Tomcat 7.0.37 JSF 应用部署 ClassNotFound FacesServlet

Question

Mar 03, 2013 12:09:05 PM org.apache.catalina.core.ApplicationContext log
INFO: Marking servlet Faces Servlet as unavailable
Mar 03, 2013 12:09:05 PM org.apache.catalina.core.StandardContext loadOnStartup
SEVERE: Servlet /mavenproject1 threw load() exception
java.lang.ClassNotFoundException: javax.faces.webapp.FacesServlet
    at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1713)
    at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1558)
    at org.apache.catalina.core.DefaultInstanceManager.loadClass(DefaultInstanceManager.java:527)
    at org.apache.catalina.core.DefaultInstanceManager.loadClassMaybePrivileged(DefaultInstanceManager.java:509)
    at org.apache.catalina.core.DefaultInstanceManager.newInstance(DefaultInstanceManager.java:137)
    at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1144)
    at org.apache.catalina.core.StandardWrapper.load(StandardWrapper.java:1088)
    at org.apache.catalina.core.StandardContext.loadOnStartup(StandardContext.java:5033)
    at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5317)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
    at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:901)
    at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:877)
    at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:633)
    at org.apache.catalina.startup.HostConfig.deployDescriptor(HostConfig.java:657)
    at org.apache.catalina.startup.HostConfig$DeployDescriptor.run(HostConfig.java:1637)
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)
    at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:334)
    at java.util.concurrent.FutureTask.run(FutureTask.java:166)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)
    at java.lang.Thread.run(Thread.java:722)

当我尝试使用 Faces Servlet 部署应用程序时，我得到了这个堆栈跟踪。
这意味着没有可用的 FacesServlet，但显然情况并非如此，因为这些库在 WAR 中可用。

jsf-api-2.2.0-m09.jar

jsf-impl-2.2.0-m09.jar

javaee-web-api-6.0.jar

我不知道可能出了什么问题。如标题所述，我在 Tomcat 7.0.37 上运行。

Answer 1

问题最有可能是 javaee-web-api-6.0.jar .这个 jar 里有 javax.servlet.*类。当 Tomcat 在这个 jar 中找到它们时，它会阻止 jar 进行类加载。这意味着根本无法加载此 jar 中的任何类!包括javax.faces.webapp.FacesServlet这是在里面。参见 servlet 规范 (3.0)，第 10.7.2 节:

The class loader that a container uses to load a servlet in a WAR must allow the developer to load any resources contained in library JARs within the WAR following normal Java SE semantics using getResource. As described in the Java EE license agreement, servlet containers that are not part of a Java EE product should not allow the application to override Java SE platform classes, such as those in the java.* and javax.* namespaces, that Java SE does not allow to be modified. The container should not allow applications to override or access the container’s implementation classes. It is recommended also that the application class loader be implemented so that classes and resources packaged within the WAR are loaded in preference to classes and resources residing in container-wide library JARs. An implementation MUST also guarantee that for every web application deployed in a container, a call to Thread.currentThread.getContextClassLoader() MUST return a ClassLoader instance that implements the contract specified in this section. Furthermore, the ClassLoader instance MUST be a separate instance for each deployed web application. The container is required to set the thread context ClassLoader as described above before making any callbacks (including listener callbacks) into the web application, and set it back to the original ClassLoader, once the callback returns.

清理你的依赖!