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 * Copyright (c) 2010, 2019 Oracle and/or its affiliates. All rights reserved.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v. 2.0, which is available at
 * http://www.eclipse.org/legal/epl-2.0.
 *
 * This Source Code may also be made available under the following Secondary
 * Licenses when the conditions for such availability set forth in the
 * Eclipse Public License v. 2.0 are satisfied: GNU General Public License,
 * version 2 with the GNU Classpath Exception, which is available at
 * https://www.gnu.org/software/classpath/license.html.
 *
 * SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
 */

package org.glassfish.jersey.server.internal.inject;

import java.util.Arrays;
import java.util.HashSet;
import java.util.Set;
import java.util.function.Function;

import javax.inject.Provider;

import org.glassfish.jersey.server.ContainerRequest;
import org.glassfish.jersey.server.model.Parameter;
import org.glassfish.jersey.server.spi.internal.ValueParamProvider;

A parameter value provider that provides parameter value factories which are using MultivaluedParameterExtractorProvider to extract parameter values from the supplied multivalued
parameter map. 
Author:
Paul Sandoz, Marek Potociar/**
 * A parameter value provider that provides parameter value factories
 * which are using {@link MultivaluedParameterExtractorProvider} to extract parameter
 * values from the supplied {@link javax.ws.rs.core.MultivaluedMap multivalued
 * parameter map}.
 *
 * @author Paul Sandoz
 * @author Marek Potociar
 */
public abstract class AbstractValueParamProvider implements ValueParamProvider {

    private final Provider<MultivaluedParameterExtractorProvider> mpep;
    private final Set<Parameter.Source> compatibleSources;

    
Initialize the provider.
Params:
mpep –              multivalued map parameter extractor provider.
compatibleSources – compatible parameter sources./**
     * Initialize the provider.
     *
     * @param mpep              multivalued map parameter extractor provider.
     * @param compatibleSources compatible parameter sources.
     */
    protected AbstractValueParamProvider(Provider<MultivaluedParameterExtractorProvider> mpep,
                                            Parameter.Source... compatibleSources) {
        this.mpep = mpep;
        this.compatibleSources = new HashSet<>(Arrays.asList(compatibleSources));
    }

    
Get a parameter extractor. The extractor returned from this method will use the default value set on the parameter, in case the parameter is not found in the supplied multivalued parameter map. 
Params:
parameter – parameter supported by the returned extractor.
Returns:
extractor supporting the parameter. The returned instance ignores
any default values set on the parameter./**
     * Get a parameter extractor.
     * The extractor returned from this method will use the default value
     * set on the parameter, in case the parameter is not found in the supplied
     * {@link javax.ws.rs.core.MultivaluedMap multivalued parameter map}.
     *
     * @param parameter parameter supported by the returned extractor.
     * @return extractor supporting the parameter. The returned instance ignores
     * any default values set on the parameter.
     */
    protected final MultivaluedParameterExtractor<?> get(Parameter parameter) {
        return mpep.get().get(parameter);
    }

    
Create a value provider for the parameter. May return null in case the parameter is not supported by the value provider. 
Params:
parameter –       parameter requesting the value provider instance.
Returns:
parameter value supplier. Returns null if parameter is not supported./**
     * Create a value provider for the parameter. May return {@code null} in case
     * the parameter is not supported by the value provider.
     *
     * @param parameter       parameter requesting the value provider instance.
     * @return parameter value supplier. Returns {@code null} if parameter is not supported.
     */
    protected abstract Function<ContainerRequest, ?> createValueProvider(Parameter parameter);

    
Get an injected value provider for the parameter. May return null in case the parameter is not supported by the value provider. 
Params:
parameter – parameter requesting the value provider instance.
Returns:
injected parameter value supplier. Returns null if parameter is not supported./**
     * Get an injected value provider for the parameter. May return {@code null}
     * in case the parameter is not supported by the value provider.
     *
     * @param parameter parameter requesting the value provider instance.
     * @return injected parameter value supplier. Returns {@code null} if parameter
     * is not supported.
     */
    @Override
    public final Function<ContainerRequest, ?> getValueProvider(Parameter parameter) {
        if (!compatibleSources.contains(parameter.getSource())) {
            // not compatible
            return null;
        }
        return createValueProvider(parameter);
    }

    @Override
    public PriorityType getPriority() {
        return Priority.NORMAL;
    }
}