[JAVA] Add arbitrary parameters to the URL output by <h: outputScript> <h: outputStylesheet> of JSF

Introduction

This is a method to dynamically add parameters at build time to get the latest Javascript and CSS loaded by JSF Facelets. Before modification) vendor.js After modification) vendor.js? V = 12345678

Goodbye to Super Reload.

procedure

Create a class that inherits the ResourceHandlerWrapper class.

CustomResourceHandler.java

package com.sample;

import java.util.Arrays;
import javax.faces.application.Resource;
import javax.faces.application.ResourceHandler;
import javax.faces.application.ResourceHandlerWrapper;
import javax.faces.application.ResourceWrapper;

public class CustomResourceHandler extends ResourceHandlerWrapper {

    private final ResourceHandler wrapped;

    public CustomResourceHandler(ResourceHandler wrapped) {
        this.wrapped = wrapped;
    }

    @Override
    public Resource createResource(String resourceName) {
        return createResource(resourceName, null, null);
    }

    @Override
    public Resource createResource(String resourceName, String libraryName) {
        return createResource(resourceName, libraryName, null);
    }

    @Override
    public Resource createResource(String resourceName, String libraryName, String contentType) {
        final Resource resource = super.createResource(resourceName, libraryName, contentType);

        if (resource == null) {
            return null;
        }

        if (!Arrays.asList("js", "css").contains(libraryName)) {
            //Target Javascript and CSS
            return resource;
        }

        return new ResourceWrapper() {

            @Override
            public String getRequestPath() {
                return super.getRequestPath() + "&(Arbitrary query parameters)";
            }

            @Override // Necessary because this is missing in ResourceWrapper (will be fixed in JSF 2.2).
            public String getResourceName() {
                return resource.getResourceName();
            }

            @Override // Necessary because this is missing in ResourceWrapper (will be fixed in JSF 2.2).
            public String getLibraryName() {
                return resource.getLibraryName();
            }

            @Override // Necessary because this is missing in ResourceWrapper (will be fixed in JSF 2.2).
            public String getContentType() {
                return resource.getContentType();
            }

            @Override
            public Resource getWrapped() {
                return resource;
            }
        };
    }

    @Override
    public ResourceHandler getWrapped() {
        return wrapped;
    }

}

Register the handler created above in faces-config.xml.

WEB-INF/faces-config.xml

<application>
  <resource-handler>com.sample.CustomResourceHandler</resource-handler>
</application>

reference

• How to use JSF versioning for resources in jar