问题描述:

创建了一个helloServlet

代码如下

package Test;

import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse; /**
* Servlet implementation class helloServlet
*/
@WebServlet("/helloServlet")
public class helloServlet extends HttpServlet {
// private static final long serialVersionUID = 1L; /**
* @see HttpServlet#HttpServlet()
*/
public helloServlet() {
super();
// TODO Auto-generated constructor stub
} /**
* @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
*/
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
response.setCharacterEncoding("GBK");
response.getWriter().write("你好 世界");
} /**
* @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
*/
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
doGet(request, response);
} }

接着配置

web.xml

代码如下:

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID" version="3.0">
<display-name>haha</display-name>
<welcome-file-list>
<welcome-file>index.html</welcome-file>
<welcome-file>index.htm</welcome-file>
<welcome-file>index.jsp</welcome-file>
<welcome-file>default.html</welcome-file>
<welcome-file>default.htm</welcome-file>
<welcome-file>default.jsp</welcome-file>
</welcome-file-list>
<servlet>
<!-- 类名 -->
<servlet-name>helloServlet</servlet-name>
<!-- 类所在的包路径 -->
<servlet-class>Test.helloServlet</servlet-class>
</servlet>
<!-- 映射路径 -->
<servlet-mapping> <servlet-name>helloServlet</servlet-name>
<url-pattern>TomcatTest/helloServlet</url-pattern>
</servlet-mapping> </web-app>

启动server

报错错误如下

Server Tomcat v7.0 Server at localhost failed to start.

日志:

十二月 28, 2018 8:45:59 下午 org.apache.catalina.startup.VersionLoggerListener log
信息: Server version: Apache Tomcat/7.0.92
十二月 28, 2018 8:45:59 下午 org.apache.catalina.startup.VersionLoggerListener log
信息: Server built: Nov 9 2018 11:07:44 UTC
十二月 28, 2018 8:45:59 下午 org.apache.catalina.startup.VersionLoggerListener log
信息: Server number: 7.0.92.0
十二月 28, 2018 8:45:59 下午 org.apache.catalina.startup.VersionLoggerListener log
信息: OS Name: Windows 10
十二月 28, 2018 8:45:59 下午 org.apache.catalina.startup.VersionLoggerListener log
信息: OS Version: 10.0
十二月 28, 2018 8:45:59 下午 org.apache.catalina.startup.VersionLoggerListener log
信息: Architecture: amd64
十二月 28, 2018 8:45:59 下午 org.apache.catalina.startup.VersionLoggerListener log
信息: Java Home: C:\Program Files\Java\jre1.8.0_161
十二月 28, 2018 8:45:59 下午 org.apache.catalina.startup.VersionLoggerListener log
信息: JVM Version: 1.8.0_161-b12
十二月 28, 2018 8:45:59 下午 org.apache.catalina.startup.VersionLoggerListener log
信息: JVM Vendor: Oracle Corporation
十二月 28, 2018 8:45:59 下午 org.apache.catalina.startup.VersionLoggerListener log
信息: CATALINA_BASE: D:\Eclipse_WorkSpace\.metadata\.plugins\org.eclipse.wst.server.core\tmp0
十二月 28, 2018 8:45:59 下午 org.apache.catalina.startup.VersionLoggerListener log
信息: CATALINA_HOME: D:\apache-tomcat-7.0.92
十二月 28, 2018 8:45:59 下午 org.apache.catalina.startup.VersionLoggerListener log
信息: Command line argument: -Dcatalina.base=D:\Eclipse_WorkSpace\.metadata\.plugins\org.eclipse.wst.server.core\tmp0
十二月 28, 2018 8:45:59 下午 org.apache.catalina.startup.VersionLoggerListener log
信息: Command line argument: -Dcatalina.home=D:\apache-tomcat-7.0.92
十二月 28, 2018 8:45:59 下午 org.apache.catalina.startup.VersionLoggerListener log
信息: Command line argument: -Dwtp.deploy=D:\Eclipse_WorkSpace\.metadata\.plugins\org.eclipse.wst.server.core\tmp0\wtpwebapps
十二月 28, 2018 8:45:59 下午 org.apache.catalina.startup.VersionLoggerListener log
信息: Command line argument: -Djava.endorsed.dirs=D:\apache-tomcat-7.0.92\endorsed
十二月 28, 2018 8:45:59 下午 org.apache.catalina.startup.VersionLoggerListener log
信息: Command line argument: -Dfile.encoding=GBK
十二月 28, 2018 8:45:59 下午 org.apache.catalina.core.AprLifecycleListener lifecycleEvent
信息: Loaded APR based Apache Tomcat Native library 1.2.18 using APR version 1.6.5.
十二月 28, 2018 8:45:59 下午 org.apache.catalina.core.AprLifecycleListener lifecycleEvent
信息: APR capabilities: IPv6 [true], sendfile [true], accept filters [false], random [true].
十二月 28, 2018 8:45:59 下午 org.apache.catalina.core.AprLifecycleListener initializeSSL
信息: OpenSSL successfully initialized (OpenSSL 1.1.1 11 Sep 2018)
十二月 28, 2018 8:45:59 下午 org.apache.coyote.AbstractProtocol init
信息: Initializing ProtocolHandler ["http-apr-8080"]
十二月 28, 2018 8:45:59 下午 org.apache.coyote.AbstractProtocol init
信息: Initializing ProtocolHandler ["ajp-apr-8009"]
十二月 28, 2018 8:45:59 下午 org.apache.catalina.startup.Catalina load
信息: Initialization processed in 439 ms
十二月 28, 2018 8:45:59 下午 org.apache.catalina.core.StandardService startInternal
信息: Starting service Catalina
十二月 28, 2018 8:45:59 下午 org.apache.catalina.core.StandardEngine startInternal
信息: Starting Servlet Engine: Apache Tomcat/7.0.92
十二月 28, 2018 8:45:59 下午 org.apache.catalina.util.SessionIdGeneratorBase createSecureRandom
警告: Creation of SecureRandom instance for session ID generation using [SHA1PRNG] took [182] milliseconds.
十二月 28, 2018 8:46:00 下午 org.apache.catalina.core.ContainerBase startInternal
严重: A child container failed during start
java.util.concurrent.ExecutionException: org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Catalina].StandardHost[localhost].StandardContext[/haha]]
at java.util.concurrent.FutureTask.report(Unknown Source)
at java.util.concurrent.FutureTask.get(Unknown Source)
at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:1243)
at org.apache.catalina.core.StandardHost.startInternal(StandardHost.java:819)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:145)
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1707)
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1697)
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: org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Catalina].StandardHost[localhost].StandardContext[/haha]]
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:162)
... 6 more
Caused by: java.lang.IllegalArgumentException: Invalid <url-pattern> TomcatTest/helloServlet in servlet mapping
at org.apache.catalina.core.StandardContext.addServletMapping(StandardContext.java:3471)
at org.apache.catalina.core.StandardContext.addServletMapping(StandardContext.java:3446)
at org.apache.catalina.deploy.WebXml.configureContext(WebXml.java:1439)
at org.apache.catalina.startup.ContextConfig.webConfig(ContextConfig.java:1352)
at org.apache.catalina.startup.ContextConfig.configureStart(ContextConfig.java:881)
at org.apache.catalina.startup.ContextConfig.lifecycleEvent(ContextConfig.java:388)
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:5566)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:145)
... 6 more 十二月 28, 2018 8:46:00 下午 org.apache.catalina.core.ContainerBase startInternal
严重: A child container failed during start
java.util.concurrent.ExecutionException: org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Catalina].StandardHost[localhost]]
at java.util.concurrent.FutureTask.report(Unknown Source)
at java.util.concurrent.FutureTask.get(Unknown Source)
at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:1243)
at org.apache.catalina.core.StandardEngine.startInternal(StandardEngine.java:300)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:145)
at org.apache.catalina.core.StandardService.startInternal(StandardService.java:444)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:145)
at org.apache.catalina.core.StandardServer.startInternal(StandardServer.java:758)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:145)
at org.apache.catalina.startup.Catalina.start(Catalina.java:710)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:294)
at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:428)
Caused by: org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Catalina].StandardHost[localhost]]
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:162)
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1707)
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1697)
at java.util.concurrent.FutureTask.run(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Caused by: org.apache.catalina.LifecycleException: A child container failed during start
at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:1254)
at org.apache.catalina.core.StandardHost.startInternal(StandardHost.java:819)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:145)
... 6 more
Caused by: java.util.concurrent.ExecutionException: org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Catalina].StandardHost[localhost].StandardContext[/haha]]
at java.util.concurrent.FutureTask.report(Unknown Source)
at java.util.concurrent.FutureTask.get(Unknown Source)
at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:1243)
... 8 more
Caused by: org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Catalina].StandardHost[localhost].StandardContext[/haha]]
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:162)
... 6 more
Caused by: java.lang.IllegalArgumentException: Invalid <url-pattern> TomcatTest/helloServlet in servlet mapping
at org.apache.catalina.core.StandardContext.addServletMapping(StandardContext.java:3471)
at org.apache.catalina.core.StandardContext.addServletMapping(StandardContext.java:3446)
at org.apache.catalina.deploy.WebXml.configureContext(WebXml.java:1439)
at org.apache.catalina.startup.ContextConfig.webConfig(ContextConfig.java:1352)
at org.apache.catalina.startup.ContextConfig.configureStart(ContextConfig.java:881)
at org.apache.catalina.startup.ContextConfig.lifecycleEvent(ContextConfig.java:388)
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:5566)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:145)
... 6 more 十二月 28, 2018 8:46:00 下午 org.apache.catalina.startup.Catalina start
严重: The required Server component failed to start so Tomcat is unable to start.
org.apache.catalina.LifecycleException: Failed to start component [StandardServer[8005]]
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:162)
at org.apache.catalina.startup.Catalina.start(Catalina.java:710)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:294)
at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:428)
Caused by: org.apache.catalina.LifecycleException: Failed to start component [StandardService[Catalina]]
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:162)
at org.apache.catalina.core.StandardServer.startInternal(StandardServer.java:758)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:145)
... 7 more
Caused by: org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Catalina]]
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:162)
at org.apache.catalina.core.StandardService.startInternal(StandardService.java:444)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:145)
... 9 more
Caused by: org.apache.catalina.LifecycleException: A child container failed during start
at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:1254)
at org.apache.catalina.core.StandardEngine.startInternal(StandardEngine.java:300)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:145)
... 11 more
Caused by: java.util.concurrent.ExecutionException: org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Catalina].StandardHost[localhost]]
at java.util.concurrent.FutureTask.report(Unknown Source)
at java.util.concurrent.FutureTask.get(Unknown Source)
at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:1243)
... 13 more
Caused by: org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Catalina].StandardHost[localhost]]
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:162)
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1707)
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1697)
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: org.apache.catalina.LifecycleException: A child container failed during start
at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:1254)
at org.apache.catalina.core.StandardHost.startInternal(StandardHost.java:819)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:145)
... 6 more
Caused by: java.util.concurrent.ExecutionException: org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Catalina].StandardHost[localhost].StandardContext[/haha]]
at java.util.concurrent.FutureTask.report(Unknown Source)
at java.util.concurrent.FutureTask.get(Unknown Source)
at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:1243)
... 8 more
Caused by: org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Catalina].StandardHost[localhost].StandardContext[/haha]]
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:162)
... 6 more
Caused by: java.lang.IllegalArgumentException: Invalid <url-pattern> TomcatTest/helloServlet in servlet mapping
at org.apache.catalina.core.StandardContext.addServletMapping(StandardContext.java:3471)
at org.apache.catalina.core.StandardContext.addServletMapping(StandardContext.java:3446)
at org.apache.catalina.deploy.WebXml.configureContext(WebXml.java:1439)
at org.apache.catalina.startup.ContextConfig.webConfig(ContextConfig.java:1352)
at org.apache.catalina.startup.ContextConfig.configureStart(ContextConfig.java:881)
at org.apache.catalina.startup.ContextConfig.lifecycleEvent(ContextConfig.java:388)
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:5566)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:145)
... 6 more 十二月 28, 2018 8:46:00 下午 org.apache.coyote.AbstractProtocol pause
信息: Pausing ProtocolHandler ["http-apr-8080"]
十二月 28, 2018 8:46:00 下午 org.apache.coyote.AbstractProtocol pause
信息: Pausing ProtocolHandler ["ajp-apr-8009"]
十二月 28, 2018 8:46:00 下午 org.apache.catalina.core.StandardService stopInternal
信息: Stopping service Catalina
十二月 28, 2018 8:46:00 下午 org.apache.coyote.AbstractProtocol destroy
信息: Destroying ProtocolHandler ["http-apr-8080"]
十二月 28, 2018 8:46:00 下午 org.apache.coyote.AbstractProtocol destroy
信息: Destroying ProtocolHandler ["ajp-apr-8009"]

解决方案:

根据日志可以分析出可能跟web.xml有关

推测是否是eclipse自动会设置映射路径,于是删掉配置的servlet

代码如下:

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID" version="3.0">
<display-name>haha</display-name>
<welcome-file-list>
<welcome-file>index.html</welcome-file>
<welcome-file>index.htm</welcome-file>
<welcome-file>index.jsp</welcome-file>
<welcome-file>default.html</welcome-file>
<welcome-file>default.htm</welcome-file>
<welcome-file>default.jsp</welcome-file>
</welcome-file-list> </web-app>

启动server

成功

问题解决

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