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1 package org.apache.lucene.index;
2
3
18
19 import java.io.IOException  ;
20 import java.util.Arrays ;
21 import java.util.Iterator ;
22 import java.util.LinkedList ;
23 import java.util.List ;
24
25 import org.apache.lucene.util.PriorityQueue;
26
27
33 public class MultipleTermPositions implements TermPositions {
34
35 private static final class TermPositionsQueue extends PriorityQueue {
36 TermPositionsQueue(List termPositions) throws IOException {
37 initialize(termPositions.size());
38
39 Iterator i = termPositions.iterator();
40 while (i.hasNext()) {
41 TermPositions tp = (TermPositions) i.next();
42 if (tp.next())
43 put(tp);
44 }
45 }
46
47 final TermPositions peek() {
48 return (TermPositions) top();
49 }
50
51 public final boolean lessThan(Object a, Object b) {
52 return ((TermPositions) a).doc() < ((TermPositions) b).doc();
53 }
54 }
55
56 private static final class IntQueue {
57 private int _arraySize = 16;
58 private int _index = 0;
59 private int _lastIndex = 0;
60 private int[] _array = new int[_arraySize];
61
62 final void add(int i) {
63 if (_lastIndex == _arraySize)
64 growArray();
65
66 _array[_lastIndex++] = i;
67 }
68
69 final int next() {
70 return _array[_index++];
71 }
72
73 final void sort() {
74 Arrays.sort(_array, _index, _lastIndex);
75 }
76
77 final void clear() {
78 _index = 0;
79 _lastIndex = 0;
80 }
81
82 final int size() {
83 return (_lastIndex - _index);
84 }
85
86 private void growArray() {
87 int[] newArray = new int[_arraySize * 2];
88 System.arraycopy(_array, 0, newArray, 0, _arraySize);
89 _array = newArray;
90 _arraySize *= 2;
91 }
92 }
93
94 private int _doc;
95 private int _freq;
96 private TermPositionsQueue _termPositionsQueue;
97 private IntQueue _posList;
98
99
104 public MultipleTermPositions(IndexReader indexReader, Term[] terms) throws IOException {
105 List termPositions = new LinkedList ();
106
107 for (int i = 0; i < terms.length; i++)
108 termPositions.add(indexReader.termPositions(terms[i]));
109
110 _termPositionsQueue = new TermPositionsQueue(termPositions);
111 _posList = new IntQueue();
112 }
113
114 public final boolean next() throws IOException {
115 if (_termPositionsQueue.size() == 0)
116 return false;
117
118 _posList.clear();
119 _doc = _termPositionsQueue.peek().doc();
120
121 TermPositions tp;
122 do {
123 tp = _termPositionsQueue.peek();
124
125 for (int i = 0; i < tp.freq(); i++)
126 _posList.add(tp.nextPosition());
127
128 if (tp.next())
129 _termPositionsQueue.adjustTop();
130 else {
131 _termPositionsQueue.pop();
132 tp.close();
133 }
134 } while (_termPositionsQueue.size() > 0 && _termPositionsQueue.peek().doc() == _doc);
135
136 _posList.sort();
137 _freq = _posList.size();
138
139 return true;
140 }
141
142 public final int nextPosition() {
143 return _posList.next();
144 }
145
146 public final boolean skipTo(int target) throws IOException {
147 while (_termPositionsQueue.peek() != null && target > _termPositionsQueue.peek().doc()) {
148 TermPositions tp = (TermPositions) _termPositionsQueue.pop();
149 if (tp.skipTo(target))
150 _termPositionsQueue.put(tp);
151 else
152 tp.close();
153 }
154 return next();
155 }
156
157 public final int doc() {
158 return _doc;
159 }
160
161 public final int freq() {
162 return _freq;
163 }
164
165 public final void close() throws IOException {
166 while (_termPositionsQueue.size() > 0)
167 ((TermPositions) _termPositionsQueue.pop()).close();
168 }
169
170
174 public void seek(Term arg0) throws IOException {
175 throw new UnsupportedOperationException ();
176 }
177
178
182 public void seek(TermEnum termEnum) throws IOException {
183 throw new UnsupportedOperationException ();
184 }
185
186
190 public int read(int[] arg0, int[] arg1) throws IOException {
191 throw new UnsupportedOperationException ();
192 }
193
194 }
195 |
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