1 /*
2 * #%L
3 * settings4j
4 * ===============================================================
5 * Copyright (C) 2008 - 2015 Brabenetz Harald, Austria
6 * ===============================================================
7 * Licensed under the Apache License, Version 2.0 (the "License");
8 * you may not use this file except in compliance with the License.
9 * You may obtain a copy of the License at
10 *
11 * http://www.apache.org/licenses/LICENSE-2.0
12 *
13 * Unless required by applicable law or agreed to in writing, software
14 * distributed under the License is distributed on an "AS IS" BASIS,
15 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16 * See the License for the specific language governing permissions and
17 * limitations under the License.
18 * #L%
19 */
20 package org.settings4j.settings;
21
22 import java.util.ArrayList;
23 import java.util.List;
24 import java.util.regex.Pattern;
25
26 import org.settings4j.Filter;
27
28 /**
29 * The Default Implementation uses the RegEx-{@link Pattern} Expressions to evaluate the includes and excludes.
30 *
31 * @author Harald.Brabenetz
32 */
33 public class DefaultFilter implements Filter {
34
35 private final List<Pattern> includePatterns = new ArrayList<Pattern>();
36 private final List<Pattern> excludePatterns = new ArrayList<Pattern>();
37
38 @Override
39 public void addExclude(final String pattern) {
40 try {
41 final Pattern p = Pattern.compile(pattern);
42 this.excludePatterns.add(p);
43 } catch (final RuntimeException e) {
44 throw new IllegalArgumentException(String.format("cannot compile exclude filter pattern '%s': %s", pattern, e.getMessage()), e);
45 }
46 }
47
48 @Override
49 public void addInclude(final String pattern) {
50 try {
51 final Pattern p = Pattern.compile(pattern);
52 this.includePatterns.add(p);
53 } catch (final RuntimeException e) {
54 throw new IllegalArgumentException(String.format("cannot compile include filter pattern '%s': %s", pattern, e.getMessage()), e);
55 }
56 }
57
58 @Override
59 public boolean isValid(final String key) {
60 // if exclude match, return always false.
61 for (final Pattern pattern : this.excludePatterns) {
62 if (pattern.matcher(key).matches()) {
63 return false;
64 }
65 }
66
67 // if no include is defined, return always true
68 if (this.includePatterns.isEmpty()) {
69 return true;
70 }
71
72 // if include match, return true.
73 for (final Pattern pattern : this.includePatterns) {
74 if (pattern.matcher(key).matches()) {
75 return true;
76 }
77 }
78
79 // no includePattern matched.
80 return false;
81 }
82
83 }