blob: 70cd2cfc28fcc9bdf0bd0c052759a9ff57d3c8e9 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
|
/*
* esodata - data structures and other things, of varying utility
* Copyright 2022, Ben Culkin
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <https://www.gnu.org/licenses/>.
*/
package bjc.data;
import java.util.*;
/**
* A Iterator which is guaranteed to never throw {@link ConcurrentModificationException}.
*
* The intended use case for this iterator is that you want to be able to modify
* a list you are iterating over, and not get an immediate exception.
*
* Note that using this is an agreement that you will not complain if it behaves
* oddly in the face of you concurrently modifying the list, as this class was
* designed with the usecase of modifying the list from the same thread, without
* invalidating the iterators. After all, there is a reason that most iterator
* types throw that exception.
*
* However, sometimes you want to play with fire, even if you might get burnt.
* This allows you to do so.
*
* @author Ben Culkin
*
* @param <ElementType> The type being iterated over.
*/
public class NonCMEIterator<ElementType> implements Iterator<ElementType> {
/**
* The list being iterated over.
*/
protected final List<ElementType> source;
/**
* The index of the current item in the list.
*/
protected int currIndex;
/**
* Create a new iterator which won't throw {@link ConcurrentModificationException}
*
* @param source The list being iterated over.
*/
public NonCMEIterator(List<ElementType> source) {
this.source = source;
this.currIndex = -1;
}
@Override
public boolean hasNext() {
return currIndex >= source.size();
}
@Override
public ElementType next() {
return source.get(++currIndex);
}
}
|