Apache Tomcat 8 仅在浏览器中呈现空白答案

【问题标题】：Apache Tomcat 8 only renders blank in browserApache Tomcat 8 仅在浏览器中呈现空白
【发布时间】：2017-12-13 22:44:30
【问题描述】：

我打开了一个 Tomcat 服务器并尝试在浏览器中访问 localhost:8080，但我看到的都是空白。当我尝试访问不存在的类似 localhost:8080/missing 的内容时也会发生这种情况，因此我会看到 404。另一件事是，虽然 Mozilla 只是显示空白，但 Chrome 会给出以下消息：“这个 localhost 页面不能成立”。我现在知道它是否相关，但是当我打开服务器时，我得到以下堆栈跟踪：

10-Jul-2017 11:45:06.353 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[]]
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:162)
    at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:753)
    at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:729)
    at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:717)
    at org.apache.catalina.startup.HostConfig.deployDirectory(HostConfig.java:1129)
    at org.apache.catalina.startup.HostConfig$DeployDirectory.run(HostConfig.java:1871)
    at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source)
    at java.util.concurrent.FutureTask.run(Unknown Source)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
    at java.lang.Thread.run(Unknown Source)
Caused by: java.lang.IllegalArgumentException: Servlet mapping specifies an unknown servlet name UploaderForm
    at org.apache.catalina.core.StandardContext.addServletMappingDecoded(StandardContext.java:3191)
    at org.apache.catalina.core.StandardContext.addServletMappingDecoded(StandardContext.java:3182)
    at org.apache.catalina.startup.ContextConfig.configureContext(ContextConfig.java:1385)
    at org.apache.catalina.startup.ContextConfig.webConfig(ContextConfig.java:1198)
    at org.apache.catalina.startup.ContextConfig.configureStart(ContextConfig.java:783)
    at org.apache.catalina.startup.ContextConfig.lifecycleEvent(ContextConfig.java:307)
    at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:95)
    at org.apache.catalina.util.LifecycleBase.fireLifecycleEvent(LifecycleBase.java:90)
    at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5213)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:145)
    ... 10 more

10-Jul-2017 11:45:06.354 SEVERE [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Error deploying web application directory G:\Tomcat\apache-tomcat-8.0.45\webapps\ROOT
 java.lang.IllegalStateException: ContainerBase.addChild: start: org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Catalina].StandardHost[localhost].StandardContext[]]
    at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:757)
    at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:729)
    at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:717)
    at org.apache.catalina.startup.HostConfig.deployDirectory(HostConfig.java:1129)
    at org.apache.catalina.startup.HostConfig$DeployDirectory.run(HostConfig.java:1871)
    at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source)
    at java.util.concurrent.FutureTask.run(Unknown Source)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
    at java.lang.Thread.run(Unknown Source)

我提到我在 Windows 10 上使用 Java 8 和 Tomcat 8.0.45。

【问题讨论】：

添加 web.xml 文件。
这里：pastebin.com/BNCrNuv3
我现在明白了，UploaderForm 不应该在那里
是的，并且 UploaderForm 只有一个映射，它缺少 <servlet> 声明。

标签： java apache tomcat java-8 tomcat8

【解决方案1】：

感谢Luciano，我设法解决了它，所以问题是我的web.xml中的这个条目：

<servlet-mapping>
   <servlet-name>UploaderForm</servlet-name>
   <url-pattern>/UploaderForm</url-pattern>
</servlet-mapping>

它不应该在那里，因为 UploaderForm 不是一个 servlet，只是 ROOT 目录中的一个 html 表单。这也在堆栈跟踪的第 14 行中指定：

Caused by: java.lang.IllegalArgumentException: Servlet mapping specifies an unknown servlet name UploaderForm

【讨论】：