blob: 77d5c063181b3698f1dcb140ed7bb735957e1052 (
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
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
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
|
package de.lmu.ifi.dbs.elki.database.ids.generic;
/*
This file is part of ELKI:
Environment for Developing KDD-Applications Supported by Index-Structures
Copyright (C) 2011
Ludwig-Maximilians-Universität München
Lehr- und Forschungseinheit für Datenbanksysteme
ELKI Development Team
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU Affero 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 Affero General Public License for more details.
You should have received a copy of the GNU Affero General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
import java.util.AbstractCollection;
import java.util.BitSet;
import java.util.Collection;
import java.util.Iterator;
import de.lmu.ifi.dbs.elki.database.ids.ArrayDBIDs;
import de.lmu.ifi.dbs.elki.database.ids.DBID;
import de.lmu.ifi.dbs.elki.database.ids.DBIDs;
/**
* View on an ArrayDBIDs masked using a BitMask for efficient mask changing.
*
* @author Erich Schubert
*
* @apiviz.uses de.lmu.ifi.dbs.elki.database.ids.DBIDs
*/
public class MaskedDBIDs extends AbstractCollection<DBID> implements DBIDs, Collection<DBID> {
/**
* Data storage
*/
protected ArrayDBIDs data;
/**
* The bitmask used for masking
*/
protected BitSet bits;
/**
* Flag whether to iterator over set or unset values.
*/
protected boolean inverse = false;
/**
* Constructor.
*
* @param data Data
* @param bits Bitset to use as mask
* @param inverse Flag to inverse the masking rule
*/
public MaskedDBIDs(ArrayDBIDs data, BitSet bits, boolean inverse) {
super();
this.data = data;
this.bits = bits;
this.inverse = inverse;
}
@Override
public Iterator<DBID> iterator() {
if(inverse) {
return new InvItr();
}
else {
return new Itr();
}
}
@Override
public Collection<DBID> asCollection() {
return this;
}
@Override
public int size() {
if(inverse) {
return data.size() - bits.cardinality();
}
else {
return bits.cardinality();
}
}
/**
* Iterator over set bits
*
* @author Erich Schubert
*
* @apiviz.exclude
*/
protected class Itr implements Iterator<DBID> {
/**
* Next position.
*/
private int pos;
/**
* Constructor
*/
protected Itr() {
this.pos = bits.nextSetBit(0);
}
@Override
public boolean hasNext() {
return (pos >= 0) && (pos < data.size());
}
@Override
public DBID next() {
DBID cur = data.get(pos);
pos = bits.nextSetBit(pos + 1);
return cur;
}
@Override
public void remove() {
throw new UnsupportedOperationException();
}
}
/**
* Iterator over unset elements.
*
* @author Erich Schubert
*
* @apiviz.exclude
*/
protected class InvItr implements Iterator<DBID> {
/**
* Next unset position.
*/
private int pos;
/**
* Constructor
*/
protected InvItr() {
this.pos = bits.nextClearBit(0);
}
@Override
public boolean hasNext() {
return (pos >= 0) && (pos < data.size());
}
@Override
public DBID next() {
DBID cur = data.get(pos);
pos = bits.nextClearBit(pos + 1);
return cur;
}
@Override
public void remove() {
throw new UnsupportedOperationException();
}
}
@Override
public boolean add(DBID e) {
throw new UnsupportedOperationException();
}
@Override
public boolean remove(Object o) {
throw new UnsupportedOperationException();
}
@Override
public void clear() {
throw new UnsupportedOperationException();
}
}
|
