services/billing-aws/src/main/java/com/epam/dlab/mongo/ResourceItemList.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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.
 */

package com.epam.dlab.mongo;

import com.epam.dlab.billing.DlabResourceType;
import com.google.common.base.MoreObjects;
import org.apache.commons.lang3.StringUtils;

import java.util.Collections;
import java.util.Comparator;
import java.util.Vector;

/**
 * List of the DLab's resources.
 */
public class ResourceItemList {
	/**
	 * List of the resources.
	 */
	private final Vector<ResourceItem> list;


	/**
	 * Constructs an empty list of resources.
	 */
	public ResourceItemList() {
		list = new Vector<>();
	}


	/**
	 * Appends the resource to the list and returns it.
	 *
	 * @param resourceId      the resource id.
	 * @param resourceName    the user friendly name of resource.
	 * @param type            the type of resource.
	 * @param user            the name of user.
	 * @param exploratoryName the name of exploratory.
	 * @return Instance of the resource.
	 */
	public ResourceItem append(String resourceId, String resourceName, DlabResourceType type, String user,
							   String exploratoryName, String project) {
		ResourceItem item = new ResourceItem(resourceId, resourceName, type, user, exploratoryName, project);
		synchronized (this) {
			int index = Collections.binarySearch(list, item);
			if (index < 0) {
				index = -index;
				if (index > list.size()) {
					list.add(item);
				} else {
					list.add(index - 1, item);
				}
			} else {
				item = list.get(index);
			}
		}
		return item;
	}

	public ResourceItem append(String resourceId, String resourceName, DlabResourceType type) {
		return append(resourceId, resourceName, type, null, null, null);
	}

	/**
	 * Returns the number of the range in list.
	 */
	public int size() {
		return list.size();
	}

	/**
	 * Returns the resource.
	 *
	 * @param index index of the resource.
	 */
	public ResourceItem get(int index) {
		return list.get(index);
	}

	/**
	 * Comparator for search resource item by resource id.
	 */
	private final ResourceItem findItemById = new ResourceItem(null, null, null, null, null, null);
	private final ComparatorByName compareByName = new ComparatorByName();

	private class ComparatorByName implements Comparator<ResourceItem> {

		@Override
		public int compare(ResourceItem o1, ResourceItem o2) {
			return StringUtils.compare(o1.resourceId, o2.resourceId);
		}

	}

	/**
	 * Find and return the resource by resource id.
	 *
	 * @param resourceId index of the resource.
	 */
	public ResourceItem getById(String resourceId) {
		findItemById.resourceId = resourceId;
		int index = Collections.binarySearch(list, findItemById, compareByName);

		return (index < 0 ? null : list.get(index));
	}

	/**
	 * Removes all of the elements from list.
	 */
	public void clear() {
		list.clear();
	}


	@Override
	public String toString() {
		return MoreObjects.toStringHelper(this).add("items", list).toString();
	}
}