org.apache.sling.scripting.sightly.use.UseProvider Maven / Gradle / Ivy

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package org.apache.sling.scripting.sightly.use;

import javax.script.Bindings;

import org.apache.sling.scripting.sightly.render.RenderContext;
import org.osgi.framework.Constants;

import aQute.bnd.annotation.ConsumerType;

/**
 * 
 * A {@code UseProvider} instantiates objects for the Use-API. Providers are queried in the descending order of their
 * {@link Constants#SERVICE_RANKING service ranking} until one is found which can provide a non-null instance.
 * 
 * 
 * The default value for the ranking if the property is missing is zero.
 * 
 */
@ConsumerType
public interface UseProvider {

    /**
     * Provide an instance based on the given identifier
     *
     * @param identifier    the identifier of the dependency
     * @param renderContext the current rendering context
     * @param arguments     Specific arguments provided by the use plugin
     * @return a container with the instance that corresponds to the identifier. If the identifier cannot be
     * handled by this provider, a failed outcome is returned
     */
    ProviderOutcome provide(String identifier, RenderContext renderContext, Bindings arguments);
}