JSF WebApp with Tomcat (which version?)

问题

I want to develop a JSF 2 web application, but I'm confused about setting up the environment files, i.e. web.xml and faces-config.xml

I would like to use JSF 2 (.xhtml), Tomcat 9.0 and Open JDK 11.0.2

I have seen this page: http://tomcat.apache.org/whichversion.html but I am not clear on the exact meaning of the columns, in particular (for the Tomcat 9.0.31 row)

Servlet Spec 4.0: does it mean I have to set web-app version = "4.0" in the web.xml file? JSP Spec 2.3: what should I set? EL 3.0 specification: does that mean I have to set faces-config version = "3.0" in the faces-config.xml file?

thank you!

回答1:

Servlet Spec 4.0: does it mean I have to set web-app version = "4.0" in the web.xml file?

Yes.

JSP Spec 2.3: what should I set?

Nothing. JSP version goes hand in hand with Servlet version. So web.xml of 4.0 is fine to activate JSP 2.3.

<?xml version="1.0" encoding="UTF-8"?>
<web-app 
    xmlns="http://xmlns.jcp.org/xml/ns/javaee"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd"
    version="4.0"
>
    <!-- Config here. -->
</web-app>

EL 3.0 specification: does that mean I have to set faces-config version = "3.0" in the faces-config.xml file?

Absolutely not. EL is not JSF. EL version also goes hand in hand with Servlet version. So web.xml of 4.0 is fine to activate EL 3.0.

The faces-config.xml version indicates JSF version. But Tomcat does not ship with JSF out the box at all. You have to install it manually. Currently available latest JSF version is 2.3, so you have to set faces-config.xml to 2.3.

<?xml version="1.0" encoding="UTF-8"?>
<faces-config
    xmlns="http://xmlns.jcp.org/xml/ns/javaee" 
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-facesconfig_2_3.xsd"
    version="2.3"
>
    <!-- Config here. -->
</faces-config>

Note that Tomcat also doesn't ship with JSTL and CDI out the box while they are also required by JSF. So you also have to manually install them both. Or, better, just pick a normal JEE server instead of a barebones servletcontainer. Then you don't need to manually install individual JEE artifacts not supported by the target servletcontainer.

See also:

• How to properly install and configure JSF libraries via Maven?
• How to install and use CDI on Tomcat?
• What exactly is Java EE?

来源：https://stackoverflow.com/questions/60487389/jsf-webapp-with-tomcat-which-version