The answer is
The issue is it is missing Dynamic Web Module facet definition. Run the following at command line
mvn eclipse:eclipse -Dwtpversion=2.0
After build is success, refresh the project and you will be add the web project to server.
Check whether your Java version is compatible with the project. Right click the project>>Properties>>Project Facets>>Java check the version is compatible with your project.
if your project maven based, you can also try updating your project maven config by selecting project. Right click project> Maven>Update Project option. it will update your project config.
Right click on the project, select properties and then select "Targeted Runtimes". Check if Tomcat is selected here.
I used mvn eclipse:eclipse -Dwtpversion=2.0 in command line in the folder where I had my pom.xml. Then I refreshed the project in eclipse IDE. After that I was able to add my project.
I didn't find the Dynamic Web Module option when I clicked on the link, then I have installed Maven(Java EE) Integration for Eclipse WTP from the Eclipse Marketplace.Then, the above steps worked.
I encountered this error even though the Project Facets were set appropriately. The problem was that the "Runtime Environment" property was not set on the server:
It simply needed to be set to the appropriate Runtime:
The only thing that worked for me was creating a
.java-version
file with "oracle64-1.8.0.112" as the only entry ( use something that is 1.6+ )
Make sure you have dynamic web module facet turned on.
The issue is incompatible web application version with the targeted server. So project facets needs to be changed. In most of the cases the "Dynamic Web Module" property. This should be the value of the servlet-api version supported by the server.
In my case,
I tried changing the web_app value in web.xml. It did not worked.
I tried changing the project facet by right clicking on project properties(as mentioned above), did not work.
What worked is: Changing "version" value as in jst.web to right version from
org.eclipse.wst.common.project.facet.core.xml file. This file is present in the .setting folder under your project root directory.
You may also look at this
Source: Stackoverflow.com