1 | /*
|
---|
2 | * Copyright 2002-2004 The Apache Software Foundation
|
---|
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 | */
|
---|
17 |
|
---|
18 | package org.apache.tools.ant.types.selectors;
|
---|
19 |
|
---|
20 | import java.io.File;
|
---|
21 | import java.util.Enumeration;
|
---|
22 |
|
---|
23 | /**
|
---|
24 | * This selector is here just to shake up your thinking a bit. Don't get
|
---|
25 | * too caught up in boolean, there are other ways you can evaluate a
|
---|
26 | * collection of selectors. This one takes a vote of the selectors it
|
---|
27 | * contains, and majority wins. You could also have an "all-but-one"
|
---|
28 | * selector, a "weighted-average" selector, and so on. These are left
|
---|
29 | * as exercises for the reader (as are the usecases where this would
|
---|
30 | * be necessary).
|
---|
31 | *
|
---|
32 | * @since 1.5
|
---|
33 | */
|
---|
34 | public class MajoritySelector extends BaseSelectorContainer {
|
---|
35 |
|
---|
36 | private boolean allowtie = true;
|
---|
37 |
|
---|
38 | /**
|
---|
39 | * Default constructor.
|
---|
40 | */
|
---|
41 | public MajoritySelector() {
|
---|
42 | }
|
---|
43 |
|
---|
44 | /**
|
---|
45 | * @return a string describing this object
|
---|
46 | */
|
---|
47 | public String toString() {
|
---|
48 | StringBuffer buf = new StringBuffer();
|
---|
49 | if (hasSelectors()) {
|
---|
50 | buf.append("{majorityselect: ");
|
---|
51 | buf.append(super.toString());
|
---|
52 | buf.append("}");
|
---|
53 | }
|
---|
54 | return buf.toString();
|
---|
55 | }
|
---|
56 |
|
---|
57 | /**
|
---|
58 | * A attribute to specify what will happen if number
|
---|
59 | * of yes votes is the same as the number of no votes
|
---|
60 | * defaults to true
|
---|
61 | *
|
---|
62 | * @param tiebreaker the value to give if there is a tie
|
---|
63 | */
|
---|
64 | public void setAllowtie(boolean tiebreaker) {
|
---|
65 | allowtie = tiebreaker;
|
---|
66 | }
|
---|
67 |
|
---|
68 | /**
|
---|
69 | * Returns true (the file is selected) if most of the other selectors
|
---|
70 | * agree. In case of a tie, go by the allowtie setting. That defaults
|
---|
71 | * to true, meaning in case of a tie, the file is selected.
|
---|
72 | *
|
---|
73 | * @param basedir the base directory the scan is being done from
|
---|
74 | * @param filename is the name of the file to check
|
---|
75 | * @param file is a java.io.File object for the filename that the selector
|
---|
76 | * can use
|
---|
77 | * @return whether the file should be selected or not
|
---|
78 | */
|
---|
79 | public boolean isSelected(File basedir, String filename, File file) {
|
---|
80 | validate();
|
---|
81 | int yesvotes = 0;
|
---|
82 | int novotes = 0;
|
---|
83 | Enumeration e = selectorElements();
|
---|
84 | boolean result;
|
---|
85 |
|
---|
86 | while (e.hasMoreElements()) {
|
---|
87 | result = ((FileSelector) e.nextElement()).isSelected(basedir,
|
---|
88 | filename, file);
|
---|
89 | if (result) {
|
---|
90 | yesvotes = yesvotes + 1;
|
---|
91 | } else {
|
---|
92 | novotes = novotes + 1;
|
---|
93 | }
|
---|
94 | }
|
---|
95 | if (yesvotes > novotes) {
|
---|
96 | return true;
|
---|
97 | } else if (novotes > yesvotes) {
|
---|
98 | return false;
|
---|
99 | }
|
---|
100 | // At this point, we know we have a tie.
|
---|
101 | return allowtie;
|
---|
102 | }
|
---|
103 | }
|
---|
104 |
|
---|