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Set default home page via <welcome-file> in JSF project

由 爱⌒轻易说出口 提交于 2019-11-26 11:54:31
BalusC

First of all, the <welcome-file> does not represent the path to the "default home page". It represents the filename of the physical file contained in the folder which you'd like to serve up as default file when a folder like /, /foo/, /foo/bar/, etc is requested.

So, in JSF 2.x flavor, that would basically be:

<welcome-file-list>
    <welcome-file>index.xhtml</welcome-file>
</welcome-file-list>

This way, if the enduser requests / and you have /index.xhtml, then it will be served. Or, if the enduser requests /foo and you have /foo/index.xhtml, then it will be served, etc. If there is no such file, then a 404 error will be returned.

Now, you appear to have mapped your FacesServlet on a prefix <url-pattern> of /faces/*. This is a leftover from JSF 1.0/1.1 ages and really not recommended these days. Perhaps you were reading an outdated tutorial targeted at JSF 1.x, or a poorly maintained tutorial which was originally written for JSF 1.x and then uncarefully updated for JSF 2.x instead of rewritten from scratch.

That tutorial did also not seem to have explained you some servlet basics. Namely, in order to get JSF components in the XHTML page to run and generate some HTML output, the FacesServlet has to be invoked when the XHTML page is being requested. When you request the XHTML page like so /index.xhtml, while the FacesServlet is being mapped on /faces/*, then it won't be invoked. The browser would then retrieve the raw unparsed JSF source code instead of the generated HTML output. You can see it by rightclick, View Source in webbrowser. You should have requested the page like so /faces/index.xhtml so that the FacesServlet can run and produce HTML output which the browser can understand and present.

That only doesn't go well together with welcome files. This totally explains why you get a "clean white" (blank) page when using index.xhtml as welcome file (some inferior webbrowsers like IE would confusingly prompt a download dialog because of missing/wrong content type on the response containing raw XHTML source code). The FacesServlet was simply not being invoked. Just get rid of the old fashioned /faces/* URL pattern and use the JSF 2.x minded *.xhtml URL pattern instead.

<servlet-mapping>
    <servlet-name>facesServlet</servlet-name>
    <url-pattern>*.xhtml</url-pattern>
</servlet-mapping>

This way the welcome files should work and you can just open JSF pages by directly requesting its physical URL without hassling with virtual URLs. This was not possible in JSF 1.x because it would let the FacesServlet run in an infinite loop calling itself and cause a stack overflow.

See also:

As to those warnings, they are unrelated but quite googlable.

webtechnelson

You can set a default page in the web.xml file to have the facesServlet invoked in JSF in 2 ways:

<web-app xmlns="http://xmlns.xyz.org/xml/ns/javaee"
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xsi:schemaLocation="http://xmlns.xyz.org/xml/ns/javaee http://xmlns.xyz.org/xml/ns/javaee/web-app_4_0.xsd"
     version="4.0">
    <servlet>
        <servlet-name>facesServlet</servlet-name>
        <servlet-class>javax.faces.webapp.FacesServlet</servlet-class>
    </servlet>
    <servlet-mapping>
        <servlet-name>facesServlet</servlet-name>
        <url-pattern>*.xhtml</url-pattern>
    </servlet-mapping>
    <welcome-file-list>
        <welcome-file>index.xhtml</welcome-file>
    </welcome-file-list>
</web-app>

or invoke the facesServlet directly from the welcome file like this:

<web-app xmlns="http://xmlns.xyz.org/xml/ns/javaee"
 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 xsi:schemaLocation="http://xmlns.xyz.org/xml/ns/javaee http://xmlns.xyz.org/xml/ns/javaee/web-app_4_0.xsd"
 version="4.0">
    <welcome-file-list>
        <welcome-file>faces/index.xhtml</welcome-file>
    </welcome-file-list>
</web-app>

I hope it helps somebody!

i think this will work

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://xmlns.xyz.org/xml/ns/javaee" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.xyz.org/xml/ns/javaee/web-app_3_1.xsd" id="WebApp_ID" version="3.1">
  <welcome-file-list>
    <welcome-file>/main/login.xhtml</welcome-file>
      </welcome-file-list>
<!--         <servlet>
        <servlet-name>login</servlet-name>
        <servlet-class>com.xyz.servlets.login</servlet-class>
    </servlet>
    <servlet-mapping>
        <servlet-name>login</servlet-name>
        <url-pattern>/login</url-pattern>
    </servlet-mapping> -->

</web-app>
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eclipse
jsf
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homescreen
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