/*
* Copyright (c) 2008-2014 MongoDB, Inc.
*
* 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.
*/
package com.mongodb;
import com.mongodb.client.MongoCursor;
import com.mongodb.client.MongoIterable;
import java.util.Collection;
class MappingIterable<U, V> implements MongoIterable<V> {
private final MongoIterable<U> iterable;
private final Function<U, V> mapper;
MappingIterable(final MongoIterable<U> iterable, final Function<U, V> mapper) {
this.iterable = iterable;
this.mapper = mapper;
}
@Override
public MongoCursor<V> iterator() {
return new MongoMappingCursor<U, V>(iterable.iterator(), mapper);
}
@Override
public V first() {
MongoCursor<V> iterator = iterator();
if (!iterator.hasNext()) {
return null;
}
return iterator.next();
}
@Override
public void forEach(final Block<? super V> block) {
iterable.forEach(new Block<U>() {
@Override
public void apply(final U document) {
block.apply(mapper.apply(document));
}
});
}
@Override
public <A extends Collection<? super V>> A into(final A target) {
forEach(new Block<V>() {
@Override
public void apply(final V v) {
target.add(v);
}
});
return target;
}
@Override
public MappingIterable<U, V> batchSize(final int batchSize) {
iterable.batchSize(batchSize);
return this;
}
@Override
public <W> MongoIterable<W> map(final Function<V, W> newMap) {
return new MappingIterable<V, W>(this, newMap);
}
}