IntroductionPrimefacePluginHowToWork

/**
* The document will details the primeface how to work and the details each file.
* Author: Prominic -Bing Li
* Data: 2019-04-26
*/

# Summary
    In short ,integrate the primeface UI framework into Grails framework ,we need follow 3 steps:
    1. When the spring framework starting ,we need loading all bean into container.
    2. Custom the Grails4PrimeFacesConfig and implements it from GrailsApplicationAware.
       Loading the Grails4PrimeFacesConfig when the spring starting.
    3. Face all /faces/** url request map to FacesServlet , this still need force register when the spring starting.

    So yo can check these steps from Grails4PrimeFacesPluginGrailsPlugin -doWithSpring method.



# Core file

    1.  Grails4PrimeFacesConfig - defined the primefeace configuration.
    2.  Grails4PrimeFacesWebAppInitializer - add WebApplicationInitializer , let the container starting can loading the primefeace config.
    3.  Grails4PrimeFacesPluginGrailsPlugin - this auto genearte by grails framework , but we need add some function into doWithSpring function.
    4.  PrimefacesBeans - this file will loading all bean when the spring starting.
    5.  SpringViewScope - this file will let spring can scan & get bean from  spring view scope. 


# Additional file
    1.PfGenerateAllCommand -- command file ,it can auto generate the bean and service from domain class.
    2.MessageSourceBean    -- message file ,it can let JSF page can loading message from i118 files.
    3.WebApplicationUtils  -- web utils file ,it can help the primefeace plugin easy work with grails .

# Config files & Resources files
    1. Tag library files .
        You can found so much *.tld from src/main/resources/WEB-INF/tld
        These fiels are tag lib fiels ,more details you found it in here :
        https://gsp.grails.org/latest/guide/taglibs.html.
        If you want work with JSP tag or other some tag in the JSF page,
        You should copy these fiels from the plugin into same foler of  your application .
    
    2. Container configuration files
        You can found some *.xml file from src/main/resources/WEB-INF.
        applicationContext.xml
        faces-config.xml 
        sotmesh.xml 

        These files will defined the JSF(Primefaces) how to correct work with grails framework.
        You must should copy these files from here to your application in same folder.
    3. Templates files
        We create a grails command file :PfGenerateAllCommand , let you can easy get the bean and service from domain class.
        So , we need some file templates to generate the file .
        The templates files exist in the src/main/resources/primefaces-templates folder.