com.github.mjeanroy.spring.mappers.iterables.LazyIterableMapper Maven / Gradle / Ivy
/**
* The MIT License (MIT)
*
* Copyright (c) 2014
*
* 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 com.github.mjeanroy.spring.mappers.iterables;
import com.github.mjeanroy.spring.mappers.objects.ObjectMapper;
import java.util.Iterator;
import static com.github.mjeanroy.spring.mappers.commons.PreConditions.notNull;
/**
* Iterable implementation that map elements from original iterables structure
* to new iterable element during iteration.
*
* This iterable can be considered as a lazy iterable implement since it
* does not map all elements at instantiation but on only during iteration.
*
* @param Type of iterable elements.
* @param Type of original iterable elements.
*/
public class LazyIterableMapper implements Iterable {
/**
* Original iterable structure.
* Each elements will be automatically mapped during iteration.
*/
private final Iterable from;
/**
* Mapper used to map original iterable structure to new elements.
*/
private final ObjectMapper mapper;
/**
* Create new lazy iterable.
*
* @param iterator Original iterable structure containing elements to map.
* @param mapper Mapper that will be used to map original objects to new objects.
*/
public LazyIterableMapper(Iterable iterator, ObjectMapper mapper) {
this.from = notNull(iterator, "Original iterator must not be null");
this.mapper = notNull(mapper, "Mapper must not be null");
}
@Override
public Iterator iterator() {
return new LazyIterableIterator(from.iterator(), mapper);
}
}