com.keetip.versio.service.impl.VersioningServiceImpl.java Source code

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Here is the source code for com.keetip.versio.service.impl.VersioningServiceImpl.java

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/*
 * Copyright (c) 2014 Keetip
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *       http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 * 
 * This product may include a number of subcomponents with separate copyright notices and
 * license terms. Your use of the source code for the these subcomponents is subject to
 * the terms and conditions of the subcomponent's license, as noted in the LICENSE file.
 */

package com.keetip.versio.service.impl;

import java.util.ArrayList;
import java.util.Collection;
import java.util.Date;
import java.util.UUID;

import org.apache.commons.lang.Validate;

import com.google.common.base.Function;
import com.google.common.base.Optional;
import com.google.common.base.Predicate;
import com.google.common.collect.ArrayListMultimap;
import com.google.common.collect.Iterables;
import com.google.common.collect.Multimap;
import com.google.common.collect.Ordering;
import com.keetip.ddd.domain.EntityNotFoundException;
import com.keetip.versio.domain.Resource;
import com.keetip.versio.domain.Revision;
import com.keetip.versio.service.ResourceProviderService;
import com.keetip.versio.service.VersioningService;

/**
 * @author keetip
 * 
 */
public class VersioningServiceImpl implements VersioningService {

    private final Multimap<ResourceKey, Resource> mResources;

    private ResourceProviderService mResourceProvider;

    public VersioningServiceImpl() {
        mResources = ArrayListMultimap.create();
    }

    public <T extends Resource> Collection<T> getResources(String projectName) {
        //mResourceProvider.getResources(projectId);
        return new ArrayList<T>();
    }

    public <T extends Resource> Optional<T> getResource(String projectName, String resourceName,
            Class<T> resourceClass) {
        return Optional.absent();
    }

    public <T extends Resource> Optional<T> getRevision(String projectName, String resourceName,
            Class<T> resourceClass, Integer revision) {
        Validate.notEmpty(projectName, "Project name is required");
        Validate.notEmpty(resourceName, "Resource name is required");

        //TODO1: resolve projectId from projectName
        UUID projectId = UUID.randomUUID();
        Optional<ResourceKey> key = resolveKey(projectId, resourceName);
        Optional<Resource> resourceHolder = null;
        if (!key.isPresent()) {
            Collection<Resource> allRevisions = mResourceProvider.getRevisions(projectId, resourceName);
        } else {
        }

        if (!key.isPresent()) {
            resourceHolder = tryLoadResource(key.get(), projectId, resourceName);
        } else {
            resourceHolder = getLatestRevision(mResources.get(key.get()));
        }
        if (resourceHolder.isPresent()) {
            Object resource = resourceHolder.get();
            return Optional.of(resourceClass.cast(resource));
        }
        return Optional.absent();
    }

    public <T extends Resource> Optional<T> getRevision(String projectName, String resourceName, Date date) {
        return null;
    }

    public Revision resolveRevision(String projectName, String resourceName, Date date) {
        return null;
    }

    private <T extends Resource> Optional<T> tryLoadResource(ResourceKey key, UUID projectId, String resourceName) {
        if (key == null) {
            key = new ResourceKey(projectId, resourceName);
        }
        try {
            Collection<T> resources = mResourceProvider.getRevisions(projectId, resourceName);
            mResources.putAll(key, resources);
            return getLatestRevision(resources);
        } catch (EntityNotFoundException exception) {
            return Optional.absent();
        }
    }

    private Optional<Resource> getRevision(ResourceKey resourceKey, final Integer revision) {
        Collection<Resource> allRevisions = mResources.get(resourceKey);
        return Iterables.tryFind(allRevisions, new Predicate<Resource>() {
            public boolean apply(Resource resource) {
                return resource.getRevision().getRevisionNumber().equals(revision);
            }
        });
    }

    private <T extends Resource> Optional<T> getLatestRevision(Collection<T> resources) {
        if (resources.isEmpty()) {
            return Optional.absent();
        }
        return Optional.of(getByLastRevisionOrdering().max(resources));
    }

    private Optional<ResourceKey> resolveKey(final UUID projectId, final String resourceName) {
        return Iterables.tryFind(mResources.keySet(), new Predicate<ResourceKey>() {
            public boolean apply(ResourceKey key) {
                return key.matches(projectId, resourceName);
            }
        });
    }

    private <T extends Resource> Ordering<T> getByLastRevisionOrdering() {
        return Ordering.natural().onResultOf(new Function<T, Integer>() {
            public Integer apply(T resource) {
                return resource.getRevision().getRevisionNumber();
            }
        }).reverse();
    }

    public void setResourceProviderService(ResourceProviderService resourceProvider) {
        Validate.notNull(resourceProvider, "ResourceProvideService is required");
        mResourceProvider = resourceProvider;
    }

    public <T extends Resource> Optional<T> getResource(String projectName, String resourceName) {
        // TODO Auto-generated method stub
        return null;
    }

    public <T extends Resource> Optional<T> getRevision(String projectName, String resourceName, Integer revision) {
        // TODO Auto-generated method stub
        return null;
    }

}