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This is the api to interact with Concourse, a schemaless and distributed version control database with optimistic availability, serializable transactions and full-text search. Concourse provides a more intuitive approach to data management that is easy to deploy, access and scale with minimal tuning while also maintaining the referential integrity and ACID characteristics of traditional database systems.

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/*
 * The MIT License (MIT)
 * 
 * Copyright (c) 2013 Jeff Nelson, Cinchapi Software Collective
 * 
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 * 
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
package org.cinchapi.concourse.util;

import java.lang.reflect.Array;
import java.util.Map;
import java.util.Set;

import org.cinchapi.concourse.annotate.UtilityClass;

import com.google.common.base.Function;
import com.google.common.collect.Sets;

/**
 * A collection of tools used to transform objects in a collection using a
 * transformation {@link Function}.
 * 
 * @author jnelson
 */
@UtilityClass
public final class Transformers {

	/**
	 * Return an array whose content is equal to the content of {@code original}
	 * after it has been transformed by {@code function}.
	 * 
	 * @param original
	 * @param function
	 * @param vClass - the class object for the type to which the items in
	 *            {@code original} will be transformed
	 * @return the transformed array
	 */
	@SuppressWarnings("unchecked")
	public static  V[] transformArray(F[] original,
			Function function, Class vClass) {
		V[] transformed = (V[]) Array.newInstance(vClass, original.length);
		for (int i = 0; i < original.length; i++) {
			F item = original[i];
			transformed[i] = function.apply(item);
		}
		return transformed;
	}

	/**
	 * Return a Map whose keys are equal to the those in {@code original} after
	 * it has been transformed by {@code function}.
	 * 
	 * WARNING: There is the potential for data loss in the
	 * event that {@code function} returns duplicate transformed results for
	 * items in {@code original}.
	 * 
	 * 
	 * @param original
	 * @param function
	 * @return the transformed Map
	 */
	public static  Map transformMap(Map original,
			Function function) {
		Map transformed = TLinkedHashMap.newTLinkedHashMap();
		for (Map.Entry entry : original.entrySet()) {
			transformed.put(function.apply(entry.getKey()), entry.getValue());
		}
		return transformed;
	}

	/**
	 * Populate {@code transformed} with the items in {@code original} after
	 * applying {@code function}.
	 * 
	 * WARNING: There is the potential for data loss in the
	 * event that {@code function} returns duplicate transformed results for
	 * items in {@code original}.
	 * 
	 * 
	 * @param original
	 * @param function
	 * @return the transformed Set
	 */
	public static  Set transformSet(Set original,
			Function function) {
		Set transformed = Sets.newLinkedHashSet();
		for (F item : original) {
			transformed.add(function.apply(item));
		}
		return transformed;
	}

}