Tomcat in Eclipse failed to start with JSF project [duplicate] - eclipse

Question

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How do I import the javax.servlet / jakarta.servlet API in my Eclipse project?
(16 answers)
Closed 6 years ago.
I have taken my "old" (created some months ago, when worked fine) JSF & maven application and started to do some refactoring and restructuralisation.
But, when I did some, the application completely stopped to work (in Eclipse, but I am afraid it will be similar in the plain Tomcat).
The log
When I add my application to Tomcat instance and start the server, the eclipse shows me dialog with message "Server Tomcat 8 (evic2 emulator) failed to start.". In the log can be seeing following exception (complete log here: http://pastebin.com/YEX60a9c) (the first exception causes server to throw three more, omited, see complete log if needed):
....
SEVERE: A child container failed during start
java.util.concurrent.ExecutionException: org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Catalina].StandardHost[localhost].StandardContext[/hg6web]]
at java.util.concurrent.FutureTask.report(FutureTask.java:122)
at java.util.concurrent.FutureTask.get(FutureTask.java:192)
at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:916)
at org.apache.catalina.core.StandardHost.startInternal(StandardHost.java:871)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1408)
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1398)
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: org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Catalina].StandardHost[localhost].StandardContext[/hg6web]]
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:154)
... 6 more
Caused by: org.apache.catalina.LifecycleException: Failed to start component [org.apache.catalina.webresources.StandardRoot#747befb5]
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:154)
at org.apache.catalina.core.StandardContext.resourcesStart(StandardContext.java:4928)
at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5058)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
... 6 more
Caused by: java.lang.IllegalArgumentException: The main resource set specified [**MYAPP**/.metadata/.plugins/org.eclipse.wst.server.core/tmp0/wtpwebapps/hg6web] is not valid
at org.apache.catalina.webresources.StandardRoot.createMainResourceSet(StandardRoot.java:723)
at org.apache.catalina.webresources.StandardRoot.startInternal(StandardRoot.java:684)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
... 9 more
Dub 28, 2016 2:06:01 DOP. org.apache.catalina.core.ContainerBase startInternal
SEVERE: 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(FutureTask.java:122)
at java.util.concurrent.FutureTask.get(FutureTask.java:192)
at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:916)
at org.apache.catalina.core.StandardEngine.startInternal(StandardEngine.java:262)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
at org.apache.catalina.core.StandardService.startInternal(StandardService.java:441)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
at org.apache.catalina.core.StandardServer.startInternal(StandardServer.java:769)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
at org.apache.catalina.startup.Catalina.start(Catalina.java:625)
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:497)
at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:351)
at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:485)
Caused by: org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Catalina].StandardHost[localhost]]
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:154)
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1408)
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1398)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
Caused by: org.apache.catalina.LifecycleException: A child container failed during start
at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:924)
at org.apache.catalina.core.StandardHost.startInternal(StandardHost.java:871)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
... 6 more
....
Root of the problem
The server cannot start because of problem with my app's component. The problem of my app - looks like - is given by this exception:
Caused by: java.lang.IllegalArgumentException: The main resource set specified [**MYAPP**/.metadata/.plugins/org.eclipse.wst.server.core/tmp0/wtpwebapps/hg6web] is not valid
This mean that there is something wrong with my app, but unfortunately not specified what.
What I tried
After lots of googling, I did not find the solution, so I have been trying these (in various combinations):
Clean tomcat
Clean Tomcat working directory
Add and remove
clean (Project -> Clean...)
rebuild using maven (mvn clean install)
reopen project
delete and import project again
delete "the problematic" folder **MYAPP**/.metadata/.plugins/org.eclipse.wst.server.core/tmp0/
delete and recreate project using maven (mvn eclipse:clean eclipse:eclipse)
create new server and use instead the old one
None of these helped. The "best" what I got was that the server started, with no error, but the application still have not been deployed properly, because the browser shows me always 404 page.
My idea
I thing the problem is not really in my application (again, before refactoring it worked well), but in the Eclipse/Tomcat environment.
My environment
I am running:
Debian Linux, amd64
Oracle java 1.8.0_60
Eclipse Mars.1 Release (4.5.1)
Apache Maven 3.0.5
Apache Tomcat 8.0.30
My app
Here is my app's pom.xml:
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<artifactId>hg6web</artifactId>
<packaging>war</packaging>
<!-- the parent project is just simple pom project -->
<parent>
<groupId>cz.martlin</groupId>
<artifactId>homeguard6local</artifactId>
<version>0.1.0</version>
</parent>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<maven.compiler.source>1.8</maven.compiler.source>
<maven.compiler.target>1.8</maven.compiler.target>
</properties>
<dependencies>
<!-- JSF stuff -->
<dependency>
<groupId>com.sun.faces</groupId>
<artifactId>jsf-api</artifactId>
<version>2.2.2</version>
</dependency>
<dependency>
<groupId>com.sun.faces</groupId>
<artifactId>jsf-impl</artifactId>
<version>2.2.2</version>
</dependency>
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>javax.servlet-api</artifactId>
<version>3.0.1</version>
</dependency>
<!-- other dependencies went here -->
</dependencies>
<build>
<plugins>
<!-- http://kosalads.blogspot.cz/2014/03/maven-deploy-war-in-tomcat-7.html -->
<!-- Tomcat plugin -->
<plugin>
<groupId>org.apache.tomcat.maven</groupId>
<artifactId>tomcat7-maven-plugin</artifactId>
<version>2.2</version>
<configuration>
<path>/${project.build.name}</path>
<update>true</update>
<url>http://localhost:8080/manager/text</url>
<username>***username***</username>
<password>***password***</password>
</configuration>
</plugin>
</plugins>
</build>
</project>
and web.xml:
<?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_2_5.xsd"
version="2.5">
<display-name>hg6web</display-name>
<servlet>
<servlet-name>Faces Servlet</servlet-name>
<servlet-class>javax.faces.webapp.FacesServlet</servlet-class>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>Faces Servlet</servlet-name>
<url-pattern>*.jsf</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>Faces Servlet</servlet-name>
<url-pattern>*.xhtml</url-pattern>
</servlet-mapping>
<context-param>
<description>State saving method: 'client' or 'server' (=default). See JSF Specification 2.5.2</description>
<param-name>javax.faces.STATE_SAVING_METHOD</param-name>
<param-value>client</param-value>
</context-param>
<context-param>
<param-name>javax.servlet.jsp.jstl.fmt.localizationContext</param-name>
<param-value>resources.application</param-value>
</context-param>
<listener>
<listener-class>com.sun.faces.config.ConfigureListener</listener-class>
</listener>
<context-param>
<param-name>javax.faces.PROJECT_STAGE</param-name>
<param-value>Development</param-value>
</context-param>
<welcome-file-list>
<welcome-file>index.xhtml</welcome-file>
</welcome-file-list>
</web-app>
The project facets (https://www.dropbox.com/s/5kvz87ooc1ftzpb/hg6web-facets.png?dl=0) of my app are
Dynamic Web Module 3.1
Java 1.8
JavaScript 1.0
JavaServerFaces 2.2
Note that the Eclipse displays following tuple of errors in Problems panel:
Cannot change version of project facet Dynamic Web Module to 2.5.
One or more constraints have not been satisfied.
But, I see this errors always regardless of the application works or not.
The question(s)
Have someone met this problem? Could someone suggest me anything else to try? Or is there anything wrong in my project's settings?
Thanks

Answer 1

The notice by #BalusC solved the problem.
I have been using Servlet version 3.0 (3.0.1) (using maven dependency), but web.xml have been configured for 2.5 and Tomcat 8 works with 3.1.
So, I changed version of javax.servlet-api to 3.1.0, updated web.xml to servlet's version (see this post) and it works.