package org.apache.lucene.analysis.ngram;
/**
* 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.
*/
import java.io.Reader;
import java.io.StringReader;
import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.analysis.BaseTokenStreamTestCase;
import org.apache.lucene.analysis.ReusableAnalyzerBase;
import org.apache.lucene.analysis.Tokenizer;
/**
* Tests {@link EdgeNGramTokenizer} for correctness.
*/
public class EdgeNGramTokenizerTest extends BaseTokenStreamTestCase {
private StringReader input;
@Override
public void setUp() throws Exception {
super.setUp();
input = new StringReader("abcde");
}
public void testInvalidInput() throws Exception {
boolean gotException = false;
try {
new EdgeNGramTokenizer(input, EdgeNGramTokenizer.Side.FRONT, 0, 0);
} catch (IllegalArgumentException e) {
gotException = true;
}
assertTrue(gotException);
}
public void testInvalidInput2() throws Exception {
boolean gotException = false;
try {
new EdgeNGramTokenizer(input, EdgeNGramTokenizer.Side.FRONT, 2, 1);
} catch (IllegalArgumentException e) {
gotException = true;
}
assertTrue(gotException);
}
public void testInvalidInput3() throws Exception {
boolean gotException = false;
try {
new EdgeNGramTokenizer(input, EdgeNGramTokenizer.Side.FRONT, -1, 2);
} catch (IllegalArgumentException e) {
gotException = true;
}
assertTrue(gotException);
}
public void testFrontUnigram() throws Exception {
EdgeNGramTokenizer tokenizer = new EdgeNGramTokenizer(input, EdgeNGramTokenizer.Side.FRONT, 1, 1);
assertTokenStreamContents(tokenizer, new String[]{"a"}, new int[]{0}, new int[]{1}, 5 /* abcde */);
}
public void testBackUnigram() throws Exception {
EdgeNGramTokenizer tokenizer = new EdgeNGramTokenizer(input, EdgeNGramTokenizer.Side.BACK, 1, 1);
assertTokenStreamContents(tokenizer, new String[]{"e"}, new int[]{4}, new int[]{5}, 5 /* abcde */);
}
public void testOversizedNgrams() throws Exception {
EdgeNGramTokenizer tokenizer = new EdgeNGramTokenizer(input, EdgeNGramTokenizer.Side.FRONT, 6, 6);
assertTokenStreamContents(tokenizer, new String[0], new int[0], new int[0], 5 /* abcde */);
}
public void testFrontRangeOfNgrams() throws Exception {
EdgeNGramTokenizer tokenizer = new EdgeNGramTokenizer(input, EdgeNGramTokenizer.Side.FRONT, 1, 3);
assertTokenStreamContents(tokenizer, new String[]{"a","ab","abc"}, new int[]{0,0,0}, new int[]{1,2,3}, 5 /* abcde */);
}
public void testBackRangeOfNgrams() throws Exception {
EdgeNGramTokenizer tokenizer = new EdgeNGramTokenizer(input, EdgeNGramTokenizer.Side.BACK, 1, 3);
assertTokenStreamContents(tokenizer, new String[]{"e","de","cde"}, new int[]{4,3,2}, new int[]{5,5,5}, 5 /* abcde */);
}
public void testReset() throws Exception {
EdgeNGramTokenizer tokenizer = new EdgeNGramTokenizer(input, EdgeNGramTokenizer.Side.FRONT, 1, 3);
assertTokenStreamContents(tokenizer, new String[]{"a","ab","abc"}, new int[]{0,0,0}, new int[]{1,2,3}, 5 /* abcde */);
tokenizer.reset(new StringReader("abcde"));
assertTokenStreamContents(tokenizer, new String[]{"a","ab","abc"}, new int[]{0,0,0}, new int[]{1,2,3}, 5 /* abcde */);
}
/** blast some random strings through the analyzer */
public void testRandomStrings() throws Exception {
Analyzer a = new ReusableAnalyzerBase() {
@Override
protected TokenStreamComponents createComponents(String fieldName, Reader reader) {
Tokenizer tokenizer = new EdgeNGramTokenizer(reader, EdgeNGramTokenizer.Side.FRONT, 2, 15);
return new TokenStreamComponents(tokenizer, tokenizer);
}
};
checkRandomData(random, a, 10000*RANDOM_MULTIPLIER);
checkRandomData(random, a, 200*RANDOM_MULTIPLIER, 8192);
Analyzer b = new ReusableAnalyzerBase() {
@Override
protected TokenStreamComponents createComponents(String fieldName, Reader reader) {
Tokenizer tokenizer = new EdgeNGramTokenizer(reader, EdgeNGramTokenizer.Side.BACK, 2, 15);
return new TokenStreamComponents(tokenizer, tokenizer);
}
};
checkRandomData(random, b, 10000*RANDOM_MULTIPLIER);
checkRandomData(random, b, 200*RANDOM_MULTIPLIER, 8192);
}
}