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
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
|
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package org.apache.felix.resolver.util;
import java.util.AbstractSet;
import java.util.Arrays;
import java.util.Collection;
import java.util.Iterator;
public class CopyOnWriteSet<E> extends AbstractSet<E> {
Object[] data;
public CopyOnWriteSet() {
data = new Object[0];
}
public CopyOnWriteSet(Collection<E> col) {
if (col instanceof CopyOnWriteSet) {
data = ((CopyOnWriteSet) col).data;
} else {
data = col.toArray(new Object[col.size()]);
}
}
@Override
public Iterator<E> iterator() {
return new Iterator<E>() {
int idx = 0;
public boolean hasNext() {
return idx < data.length;
}
@SuppressWarnings("unchecked")
public E next() {
return (E) data[idx++];
}
public void remove() {
CopyOnWriteSet.this.remove(--idx);
}
};
}
@Override
public int size() {
return data.length;
}
@Override
public boolean add(E e) {
Object[] d = data;
if (d.length == 0) {
data = new Object[] {e};
} else {
for (Object o : d) {
if (o == null ? e == null : o.equals(e)) {
return false;
}
}
Object[] a = new Object[d.length + 1];
System.arraycopy(d, 0, a, 0, d.length);
a[d.length] = e;
data = a;
}
return true;
}
private void remove(int index) {
Object[] d = data;
int len = d.length;
Object[] a = new Object[len - 1];
int numMoved = len - index - 1;
if (index > 0) {
System.arraycopy(d, 0, a, 0, index);
}
if (numMoved > 0) {
System.arraycopy(d, index + 1, a, index, numMoved);
}
data = a;
}
@Override
public boolean equals(Object o) {
if (o instanceof CopyOnWriteSet && ((CopyOnWriteSet) o).data == data) {
return true;
}
return super.equals(o);
}
@Override
public int hashCode() {
return Arrays.hashCode(data);
}
}
|
