package org.apache.lucene.misc;
/**
* Copyright 2006 The Apache Software Foundation
*
* Licensed 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.
*/
import junit.framework.TestCase;
import org.apache.lucene.index.Term;
import org.apache.lucene.index.IndexWriter;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.search.Similarity;
import org.apache.lucene.search.DefaultSimilarity;
import org.apache.lucene.search.TermQuery;
import org.apache.lucene.search.HitCollector;
import org.apache.lucene.store.RAMDirectory;
import org.apache.lucene.store.Directory;
import org.apache.lucene.analysis.SimpleAnalyzer;
import org.apache.lucene.document.Document;
import org.apache.lucene.document.Field;
/**
* Tests changing the norms after changing the simularity
*
* @version $Id:$
*/
public class TestLengthNormModifier extends TestCase {
public TestLengthNormModifier(String name) {
super(name);
}
public static byte DEFAULT_NORM = Similarity.encodeNorm(1.0f);
public static int NUM_DOCS = 5;
public Directory store = new RAMDirectory();
/** inverts the normal notion of lengthNorm */
public static Similarity s = new DefaultSimilarity() {
public float lengthNorm(String fieldName, int numTokens) {
return (float)numTokens;
}
};
public void setUp() throws Exception {
IndexWriter writer = new
IndexWriter(store, new SimpleAnalyzer(), true);
IndexSearcher searcher;
for (int i = 0; i < NUM_DOCS; i++) {
Document d = new Document();
d.add(new Field("field", "word",
Field.Store.YES, Field.Index.TOKENIZED));
d.add(new Field("nonorm", "word",
Field.Store.YES, Field.Index.NO_NORMS));
for (int j = 1; j <= i; j++) {
d.add(new Field("field", "crap",
Field.Store.YES, Field.Index.TOKENIZED));
d.add(new Field("nonorm", "more words",
Field.Store.YES, Field.Index.NO_NORMS));
}
writer.addDocument(d);
}
writer.close();
}
public void testMissingField() {
LengthNormModifier lnm = new LengthNormModifier(store, s);
try {
lnm.reSetNorms("nobodyherebutuschickens");
} catch (Exception e) {
assertNull("caught something", e);
}
}
public void testFieldWithNoNorm() throws Exception {
IndexReader r = IndexReader.open(store);
byte[] norms = r.norms("nonorm");
// sanity check, norms should all be 1
assertTrue("Whoops we have norms?", !r.hasNorms("nonorm"));
for (int i = 0; i< norms.length; i++) {
assertEquals(""+i, DEFAULT_NORM, norms[i]);
}
r.close();
LengthNormModifier lnm = new LengthNormModifier(store, s);
try {
lnm.reSetNorms("nonorm");
} catch (Exception e) {
assertNull("caught something", e);
}
// nothing should have changed
r = IndexReader.open(store);
norms = r.norms("nonorm");
assertTrue("Whoops we have norms?", !r.hasNorms("nonorm"));
for (int i = 0; i< norms.length; i++) {
assertEquals(""+i, DEFAULT_NORM, norms[i]);
}
r.close();
}
public void testGoodCases() throws Exception {
IndexSearcher searcher;
final float[] scores = new float[NUM_DOCS];
float lastScore = 0.0f;
// default similarity should put docs with shorter length first
searcher = new IndexSearcher(store);
searcher.search
(new TermQuery(new Term("field", "word")),
new HitCollector() {
public final void collect(int doc, float score) {
scores[doc] = score;
}
});
searcher.close();
lastScore = Float.MAX_VALUE;
for (int i = 0; i < NUM_DOCS; i++) {
String msg = "i=" + i + ", "+scores[i]+" <= "+lastScore;
assertTrue(msg, scores[i] <= lastScore);
//System.out.println(msg);
lastScore = scores[i];
}
// override the norms to be inverted
Similarity s = new DefaultSimilarity() {
public float lengthNorm(String fieldName, int numTokens) {
return (float)numTokens;
}
};
LengthNormModifier lnm = new LengthNormModifier(store, s);
lnm.reSetNorms("field");
// new norm (with default similarity) should put longer docs first
searcher = new IndexSearcher(store);
searcher.search
(new TermQuery(new Term("field", "word")),
new HitCollector() {
public final void collect(int doc, float score) {
scores[doc] = score;
}
});
searcher.close();
lastScore = 0.0f;
for (int i = 0; i < NUM_DOCS; i++) {
String msg = "i=" + i + ", "+scores[i]+" >= "+lastScore;
assertTrue(msg, scores[i] >= lastScore);
//System.out.println(msg);
lastScore = scores[i];
}
}
}