1 /*
2 * Licensed under the Apache License, Version 2.0 (the "License");
3 * you may not use this file except in compliance with the License.
4 * You may obtain a copy of the License at
5 *
6 * http://www.apache.org/licenses/LICENSE-2.0
7 *
8 * Unless required by applicable law or agreed to in writing, software
9 * distributed under the License is distributed on an "AS IS" BASIS,
10 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
11 * See the License for the specific language governing permissions and
12 * limitations under the License.
13 */
14
15 package org.apache.commons.functor.generator;
16
17 import java.util.Collection;
18
19 import org.apache.commons.functor.Function;
20 import org.apache.commons.functor.generator.util.CollectionTransformer;
21
22 /**
23 * Base class for generators. Adds support for all of the Algorithms to
24 * each subclass.
25 *
26 * @param <E> the type of elements held in this generator.
27 * @since 1.0
28 * @version $Revision: 1522355 $ $Date: 2013-09-12 06:29:46 +0200 (Do, 12 Sep 2013) $
29 */
30 public abstract class BaseGenerator<E> implements Generator<E> {
31
32 /** Create a new generator. */
33 public BaseGenerator() {
34 super();
35 }
36
37 /**
38 * {@inheritDoc}
39 * Transforms this generator using the passed in
40 * Function. An example function might turn the contents of the
41 * generator into a {@link Collection} of elements.
42 */
43 public final <T> T to(Function<Generator<? extends E>, ? extends T> transformer) {
44 return transformer.evaluate(this);
45 }
46
47 /**
48 * {@inheritDoc}
49 * Same as to(new CollectionTransformer(collection)).
50 */
51 public final <C extends Collection<? super E>> C to(C collection) {
52 return to(new CollectionTransformer<E, C>(collection));
53 }
54
55 /**
56 * {@inheritDoc}
57 * Same as to(new CollectionTransformer()).
58 */
59 public final Collection<E> toCollection() {
60 return to(CollectionTransformer.<E> toCollection());
61 }
62 }