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 * Copyright (c) 2012, 2018 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.model;

import java.util.ArrayList;
import java.util.Collections;
import java.util.IdentityHashMap;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import java.util.Set;

import org.glassfish.jersey.internal.util.collection.Value;
import org.glassfish.jersey.internal.util.collection.Values;

Resource model of the deployed application which contains set of root resources. As it implements ResourceModelComponent it can be validated by component model validator which will perform validation of the entire resource model including all sub components (resources, resource methods ...). 
Author:
Miroslav Fuksa/**
 * Resource model of the deployed application which contains set of root resources. As it implements {@link
 * ResourceModelComponent} it can be validated by {@link ComponentModelValidator component model validator} which will perform
 * validation of the entire resource model including all sub components ({@link Resource resources},
 * {@link ResourceMethod resource methods} ...).
 *
 * @author Miroslav Fuksa
 */
public class ResourceModel implements ResourceModelComponent {

    
Builder used to create resource model instances. /**
     * Builder used to create {@link ResourceModel resource model} instances.
     */
    public static class Builder {
        private final List<Resource> resources;
        private final boolean subResourceModel;


        
Create new builder pre initialized with resourceModel. 
Params:
resourceModel –    Resource model.
subResourceModel – true if resource model created by this builder will be sub resource model, false if it is a application root resource model./**
         * Create new builder pre initialized with {@code resourceModel}.
         *
         * @param resourceModel    Resource model.
         * @param subResourceModel {@code true} if resource model created by this builder will be sub resource model,
         *                         {@code false} if it is a application root resource model.
         */
        public Builder(ResourceModel resourceModel, boolean subResourceModel) {
            this.resources = resourceModel.getResources();
            this.subResourceModel = subResourceModel;
        }

        
Create new builder pre initialized with resource. 
Params:
resources –        Resources (root and non root).
subResourceModel – true if resource model created by this builder will be sub resource model, false if it is a application root resource model./**
         * Create new builder pre initialized with {@code resource}.
         *
         * @param resources        Resources (root and non root).
         * @param subResourceModel {@code true} if resource model created by this builder will be sub resource model,
         *                         {@code false} if it is a application root resource model.
         */
        public Builder(List<Resource> resources, boolean subResourceModel) {
            this.resources = resources;
            this.subResourceModel = subResourceModel;
        }

        
Create new builder with empty resources.
Params:
subResourceModel – true if resource model created by this builder will be sub resource model, false if it is a application root resource model./**
         * Create new builder with empty resources.
         *
         * @param subResourceModel {@code true} if resource model created by this builder will be sub resource model,
         *                         {@code false} if it is a application root resource model.
         */
        public Builder(boolean subResourceModel) {
            this.resources = new ArrayList<>();
            this.subResourceModel = subResourceModel;
        }


        
Add a resource to the builder.
Params:
resource – Resource to be added to the builder (root or non root resource).
Returns:
Current builder./**
         * Add a resource to the builder.
         *
         * @param resource Resource to be added to the builder (root or non root resource).
         * @return Current builder.
         */
        public Builder addResource(Resource resource) {
            this.resources.add(resource);
            return this;
        }

        
Build the resource model. Resources with the same path are merged. 
Returns:
Resource model./**
         * Build the {@link ResourceModel resource model}. Resources with the same path are merged.
         *
         * @return Resource model.
         */
        public ResourceModel build() {
            Map<String, Resource> resourceMap = new LinkedHashMap<>();
            // resource with no path that should not be merged
            final Set<Resource> separateResources = Collections.newSetFromMap(new IdentityHashMap<>());

            for (Resource resource : resources) {
                final String path = resource.getPath();
                if (path == null && !subResourceModel) {
                    separateResources.add(resource);
                } else {
                    final Resource fromMap = resourceMap.get(path);
                    if (fromMap == null) {
                        resourceMap.put(path, resource);
                    } else {
                        resourceMap.put(path, Resource.builder(fromMap).mergeWith(resource).build());
                    }
                }
            }
            List<Resource> rootResources = new ArrayList<>();
            List<Resource> allResources = new ArrayList<>();

            for (Map.Entry<String, Resource> entry : resourceMap.entrySet()) {
                if (entry.getKey() != null) {
                    rootResources.add(entry.getValue());
                }
                allResources.add(entry.getValue());
            }
            if (!subResourceModel) {
                allResources.addAll(separateResources);
            }

            return new ResourceModel(rootResources, allResources);
        }
    }

    private final List<Resource> rootResources;
    private final List<Resource> resources;

    private final Value<RuntimeResourceModel> runtimeRootResourceModelValue;

    
Creates new instance from root allResources.
Params:
allResources – Root resource of the resource model./**
     * Creates new instance from root allResources.
     *
     * @param allResources Root resource of the resource model.
     */
    private ResourceModel(List<Resource> rootResources, List<Resource> allResources) {
        this.resources = allResources;
        this.rootResources = rootResources;
        this.runtimeRootResourceModelValue = Values.lazy(new Value<RuntimeResourceModel>() {
            @Override
            public RuntimeResourceModel get() {
                return new RuntimeResourceModel(ResourceModel.this.resources);
            }
        });
    }


    
Return root resources from this resource model.
Returns:
List of root resources./**
     * Return root resources from this resource model.
     *
     * @return List of root resources.
     */
    public List<Resource> getRootResources() {
        return rootResources;
    }

    
Return all resources from this resource model.
Returns:
List of all resources (root and non root resources)./**
     * Return all resources from this resource model.
     *
     * @return List of all resources (root and non root resources).
     */
    public List<Resource> getResources() {
        return resources;
    }

    @Override
    public void accept(ResourceModelVisitor visitor) {
        visitor.visitResourceModel(this);
    }

    @Override
    public List<? extends ResourceModelComponent> getComponents() {
        List<ResourceModelComponent> components = new ArrayList<>();

        components.addAll(resources);
        components.addAll(getRuntimeResourceModel().getRuntimeResources());
        return components;
    }

    
Return runtime resource model based on this this resource model. 
Returns:
Runtime resource model created from this resource model./**
     * Return {@link RuntimeResourceModel runtime resource model} based on this this resource model.
     *
     * @return Runtime resource model created from this resource model.
     */
    public RuntimeResourceModel getRuntimeResourceModel() {
        return runtimeRootResourceModelValue.get();
    }
}