1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache License, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17 package org.apache.commons.text.translate;
18
19 import java.io.IOException;
20 import java.io.Writer;
21 import java.util.ArrayList;
22 import java.util.List;
23 import java.util.Objects;
24 import java.util.stream.Stream;
25
26 /**
27 * Executes a sequence of translators one after the other. Execution ends whenever
28 * the first translator consumes code points from the input.
29 *
30 * @since 1.0
31 */
32 public class AggregateTranslator extends CharSequenceTranslator {
33
34 /**
35 * Translator list.
36 */
37 private final List<CharSequenceTranslator> translators = new ArrayList<>();
38
39 /**
40 * Specify the translators to be used at creation time.
41 *
42 * @param translators CharSequenceTranslator array to aggregate
43 */
44 public AggregateTranslator(final CharSequenceTranslator... translators) {
45 if (translators != null) {
46 Stream.of(translators).filter(Objects::nonNull).forEach(this.translators::add);
47 }
48 }
49
50 /**
51 * The first translator to consume code points from the input is the 'winner'.
52 * Execution stops with the number of consumed code points being returned.
53 * {@inheritDoc}
54 */
55 @Override
56 public int translate(final CharSequence input, final int index, final Writer writer) throws IOException {
57 for (final CharSequenceTranslator translator : translators) {
58 final int consumed = translator.translate(input, index, writer);
59 if (consumed != 0) {
60 return consumed;
61 }
62 }
63 return 0;
64 }
65
66 }