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1 package org.apache.lucene.search;
2
3
18
19 import java.io.IOException  ;
20 import java.util.ArrayList ;
21 import java.util.Iterator ;
22 import java.util.Vector ;
23
24 import org.apache.lucene.index.IndexReader;
25 import org.apache.lucene.index.MultipleTermPositions;
26 import org.apache.lucene.index.Term;
27 import org.apache.lucene.index.TermPositions;
28 import org.apache.lucene.search.Query;
29 import org.apache.lucene.util.ToStringUtils;
30
31
42 public class MultiPhraseQuery extends Query {
43 private String field;
44 private ArrayList termArrays = new ArrayList ();
45 private Vector positions = new Vector ();
46
47 private int slop = 0;
48
49
52 public void setSlop(int s) { slop = s; }
53
54
57 public int getSlop() { return slop; }
58
59
62 public void add(Term term) { add(new Term[]{term}); }
63
64
69 public void add(Term[] terms) {
70 int position = 0;
71 if (positions.size() > 0)
72 position = ((Integer ) positions.lastElement()).intValue() + 1;
73
74 add(terms, position);
75 }
76
77
84 public void add(Term[] terms, int position) {
85 if (termArrays.size() == 0)
86 field = terms[0].field();
87
88 for (int i = 0; i < terms.length; i++) {
89 if (terms[i].field() != field) {
90 throw new IllegalArgumentException (
91 "All phrase terms must be in the same field (" + field + "): "
92 + terms[i]);
93 }
94 }
95
96 termArrays.add(terms);
97 positions.addElement(new Integer (position));
98 }
99
100
103 public int[] getPositions() {
104 int[] result = new int[positions.size()];
105 for (int i = 0; i < positions.size(); i++)
106 result[i] = ((Integer ) positions.elementAt(i)).intValue();
107 return result;
108 }
109
110 private class MultiPhraseWeight implements Weight {
111 private Similarity similarity;
112 private float value;
113 private float idf;
114 private float queryNorm;
115 private float queryWeight;
116
117 public MultiPhraseWeight(Searcher searcher)
118 throws IOException {
119 this.similarity = getSimilarity(searcher);
120
121 Iterator i = termArrays.iterator();
123 while (i.hasNext()) {
124 Term[] terms = (Term[])i.next();
125 for (int j=0; j<terms.length; j++) {
126 idf += getSimilarity(searcher).idf(terms[j], searcher);
127 }
128 }
129 }
130
131 public Query getQuery() { return MultiPhraseQuery.this; }
132 public float getValue() { return value; }
133
134 public float sumOfSquaredWeights() {
135 queryWeight = idf * getBoost(); return queryWeight * queryWeight; }
138
139 public void normalize(float queryNorm) {
140 this.queryNorm = queryNorm;
141 queryWeight *= queryNorm; value = queryWeight * idf; }
144
145 public Scorer scorer(IndexReader reader) throws IOException {
146 if (termArrays.size() == 0) return null;
148
149 TermPositions[] tps = new TermPositions[termArrays.size()];
150 for (int i=0; i<tps.length; i++) {
151 Term[] terms = (Term[])termArrays.get(i);
152
153 TermPositions p;
154 if (terms.length > 1)
155 p = new MultipleTermPositions(reader, terms);
156 else
157 p = reader.termPositions(terms[0]);
158
159 if (p == null)
160 return null;
161
162 tps[i] = p;
163 }
164
165 if (slop == 0)
166 return new ExactPhraseScorer(this, tps, getPositions(), similarity,
167 reader.norms(field));
168 else
169 return new SloppyPhraseScorer(this, tps, getPositions(), similarity,
170 slop, reader.norms(field));
171 }
172
173 public Explanation explain(IndexReader reader, int doc)
174 throws IOException {
175 Explanation result = new Explanation();
176 result.setDescription("weight("+getQuery()+" in "+doc+"), product of:");
177
178 Explanation idfExpl = new Explanation(idf, "idf("+getQuery()+")");
179
180 Explanation queryExpl = new Explanation();
182 queryExpl.setDescription("queryWeight(" + getQuery() + "), product of:");
183
184 Explanation boostExpl = new Explanation(getBoost(), "boost");
185 if (getBoost() != 1.0f)
186 queryExpl.addDetail(boostExpl);
187
188 queryExpl.addDetail(idfExpl);
189
190 Explanation queryNormExpl = new Explanation(queryNorm,"queryNorm");
191 queryExpl.addDetail(queryNormExpl);
192
193 queryExpl.setValue(boostExpl.getValue() *
194 idfExpl.getValue() *
195 queryNormExpl.getValue());
196
197 result.addDetail(queryExpl);
198
199 Explanation fieldExpl = new Explanation();
201 fieldExpl.setDescription("fieldWeight("+getQuery()+" in "+doc+
202 "), product of:");
203
204 Explanation tfExpl = scorer(reader).explain(doc);
205 fieldExpl.addDetail(tfExpl);
206 fieldExpl.addDetail(idfExpl);
207
208 Explanation fieldNormExpl = new Explanation();
209 byte[] fieldNorms = reader.norms(field);
210 float fieldNorm =
211 fieldNorms!=null ? Similarity.decodeNorm(fieldNorms[doc]) : 0.0f;
212 fieldNormExpl.setValue(fieldNorm);
213 fieldNormExpl.setDescription("fieldNorm(field="+field+", doc="+doc+")");
214 fieldExpl.addDetail(fieldNormExpl);
215
216 fieldExpl.setValue(tfExpl.getValue() *
217 idfExpl.getValue() *
218 fieldNormExpl.getValue());
219
220 result.addDetail(fieldExpl);
221
222 result.setValue(queryExpl.getValue() * fieldExpl.getValue());
224
225 if (queryExpl.getValue() == 1.0f)
226 return fieldExpl;
227
228 return result;
229 }
230 }
231
232 public Query rewrite(IndexReader reader) {
233 if (termArrays.size() == 1) { Term[] terms = (Term[])termArrays.get(0);
235 BooleanQuery boq = new BooleanQuery(true);
236 for (int i=0; i<terms.length; i++) {
237 boq.add(new TermQuery(terms[i]), BooleanClause.Occur.SHOULD);
238 }
239 boq.setBoost(getBoost());
240 return boq;
241 } else {
242 return this;
243 }
244 }
245
246 protected Weight createWeight(Searcher searcher) throws IOException {
247 return new MultiPhraseWeight(searcher);
248 }
249
250
251 public final String toString(String f) {
252 StringBuffer buffer = new StringBuffer ();
253 if (!field.equals(f)) {
254 buffer.append(field);
255 buffer.append(":");
256 }
257
258 buffer.append("\"");
259 Iterator i = termArrays.iterator();
260 while (i.hasNext()) {
261 Term[] terms = (Term[])i.next();
262 if (terms.length > 1) {
263 buffer.append("(");
264 for (int j = 0; j < terms.length; j++) {
265 buffer.append(terms[j].text());
266 if (j < terms.length-1)
267 buffer.append(" ");
268 }
269 buffer.append(")");
270 } else {
271 buffer.append(terms[0].text());
272 }
273 if (i.hasNext())
274 buffer.append(" ");
275 }
276 buffer.append("\"");
277
278 if (slop != 0) {
279 buffer.append("~");
280 buffer.append(slop);
281 }
282
283 buffer.append(ToStringUtils.boost(getBoost()));
284
285 return buffer.toString();
286 }
287
288
289
290 public boolean equals(Object o) {
291 if (!(o instanceof MultiPhraseQuery)) return false;
292 MultiPhraseQuery other = (MultiPhraseQuery)o;
293 return this.getBoost() == other.getBoost()
294 && this.slop == other.slop
295 && this.termArrays.equals(other.termArrays)
296 && this.positions.equals(other.positions);
297 }
298
299
300 public int hashCode() {
301 return Float.floatToIntBits(getBoost())
302 ^ slop
303 ^ termArrays.hashCode()
304 ^ positions.hashCode()
305 ^ 0x4AC65113;
306 }
307 }
308 |
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