1 /*
2 * Copyright 2007 Kasper B. Graversen
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16 package org.supercsv.comment;
17
18 import java.util.regex.Pattern;
19 import java.util.regex.PatternSyntaxException;
20
21 /**
22 * CommentMatcher that matches lines that match a specified regular expression.
23 */
24 public class CommentMatches implements CommentMatcher {
25
26 private final Pattern pattern;
27
28 /**
29 * Constructs a new <tt>CommentMatches</tt> comment matcher. Ensure that the regex is efficient (ideally matching start/end
30 * characters) as a complex regex can significantly slow down reading.
31 *
32 * @param regex
33 * the regular expression a line must match to be a comment
34 * @throws NullPointerException
35 * if regex is null
36 * @throws IllegalArgumentException
37 * if regex is empty
38 * @throws PatternSyntaxException
39 * if the regex is invalid
40 */
41 public CommentMatches(final String regex) {
42 if( regex == null ) {
43 throw new NullPointerException("regex should not be null");
44 } else if( regex.length() == 0 ) {
45 throw new IllegalArgumentException("regex should not be empty");
46 }
47 this.pattern = Pattern.compile(regex);
48 }
49
50 /**
51 * {@inheritDoc}
52 */
53 public boolean isComment(String line) {
54 return pattern.matcher(line).matches();
55 }
56
57 }