/* * 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. */ package org.apache.lucene.analysis.ngram; import java.io.IOException; import java.io.StringReader; import java.util.Random; import org.apache.lucene.analysis.Analyzer; import org.apache.lucene.analysis.BaseTokenStreamTestCase; import org.apache.lucene.analysis.MockTokenizer; import org.apache.lucene.analysis.TokenFilter; import org.apache.lucene.analysis.TokenStream; import org.apache.lucene.analysis.Tokenizer; import org.apache.lucene.analysis.core.KeywordTokenizer; import org.apache.lucene.analysis.core.LetterTokenizer; import org.apache.lucene.analysis.core.WhitespaceTokenizer; import org.apache.lucene.analysis.shingle.ShingleFilter; import org.apache.lucene.analysis.tokenattributes.CharTermAttribute; import org.apache.lucene.analysis.tokenattributes.OffsetAttribute; import org.apache.lucene.analysis.tokenattributes.PositionIncrementAttribute; import org.apache.lucene.util.TestUtil; /** * Tests {@link EdgeNGramTokenFilter} for correctness. */ public class EdgeNGramTokenFilterTest extends BaseTokenStreamTestCase { private TokenStream input; @Override public void setUp() throws Exception { super.setUp(); input = whitespaceMockTokenizer("abcde"); } public void testInvalidInput() throws Exception { expectThrows(IllegalArgumentException.class, () -> { new EdgeNGramTokenFilter(input, 0, 0, false); }); } public void testInvalidInput2() throws Exception { expectThrows(IllegalArgumentException.class, () -> { new EdgeNGramTokenFilter(input, 2, 1, false); }); } public void testInvalidInput3() throws Exception { expectThrows(IllegalArgumentException.class, () -> { new EdgeNGramTokenFilter(input, -1, 2, false); }); } public void testFrontUnigram() throws Exception { EdgeNGramTokenFilter tokenizer = new EdgeNGramTokenFilter(input, 1, 1, false); assertTokenStreamContents(tokenizer, new String[]{"a"}, new int[]{0}, new int[]{5}); } public void testOversizedNgrams() throws Exception { EdgeNGramTokenFilter tokenizer = new EdgeNGramTokenFilter(input, 6, 6, false); assertTokenStreamContents(tokenizer, new String[0], new int[0], new int[0]); } public void testOversizedNgramsPreserveOriginal() throws Exception { EdgeNGramTokenFilter tokenizer = new EdgeNGramTokenFilter(input, 6, 6, true); assertTokenStreamContents(tokenizer, new String[] {"abcde"}, new int[] {0}, new int[] {5}); } public void testPreserveOriginal() throws Exception { final String inputString = "a bcd efghi jk"; { // preserveOriginal = false TokenStream ts = whitespaceMockTokenizer(inputString); EdgeNGramTokenFilter filter = new EdgeNGramTokenFilter(ts, 2, 3, false); assertTokenStreamContents(filter, new String[] { "bc", "bcd", "ef", "efg", "jk" }, new int[] { 2, 2, 6, 6, 12 }, new int[] { 5, 5, 11, 11, 14 }, new int[] { 2, 0, 1, 0, 1 }); } { // preserveOriginal = true TokenStream ts = whitespaceMockTokenizer(inputString); EdgeNGramTokenFilter filter = new EdgeNGramTokenFilter(ts, 2, 3, true); assertTokenStreamContents(filter, new String[] { "a", "bc", "bcd", "ef", "efg", "efghi", "jk" }, new int[] { 0, 2, 2, 6, 6, 6, 12 }, new int[] { 1, 5, 5, 11, 11, 11, 14 }, new int[] { 1, 1, 0, 1, 0, 0, 1 }); } } public void testFrontRangeOfNgrams() throws Exception { EdgeNGramTokenFilter tokenizer = new EdgeNGramTokenFilter(input, 1, 3, false); assertTokenStreamContents(tokenizer, new String[]{"a","ab","abc"}, new int[]{0,0,0}, new int[]{5,5,5}); } public void testFilterPositions() throws Exception { TokenStream ts = whitespaceMockTokenizer("abcde vwxyz"); EdgeNGramTokenFilter tokenizer = new EdgeNGramTokenFilter(ts, 1, 3, false); assertTokenStreamContents(tokenizer, new String[] {"a","ab","abc","v","vw","vwx"}, new int[] {0, 0, 0, 6, 6, 6}, new int[] {5, 5, 5, 11, 11, 11}); } private static class PositionFilter extends TokenFilter { private final PositionIncrementAttribute posIncrAtt = addAttribute(PositionIncrementAttribute.class); private boolean started; PositionFilter(final TokenStream input) { super(input); } @Override public final boolean incrementToken() throws IOException { if (input.incrementToken()) { if (started) { posIncrAtt.setPositionIncrement(0); } else { started = true; } return true; } else { return false; } } @Override public void reset() throws IOException { super.reset(); started = false; } } public void testFirstTokenPositionIncrement() throws Exception { TokenStream ts = whitespaceMockTokenizer("a abc"); ts = new PositionFilter(ts); // All but first token will get 0 position increment EdgeNGramTokenFilter filter = new EdgeNGramTokenFilter(ts, 2, 3, false); // The first token "a" will not be output, since it's smaller than the mingram size of 2. // The second token on input to EdgeNGramTokenFilter will have position increment of 0, // which should be increased to 1, since this is the first output token in the stream. assertTokenStreamContents(filter, new String[] { "ab", "abc" }, new int[] { 2, 2 }, new int[] { 5, 5 }, new int[] { 1, 0 } ); } public void testSmallTokenInStream() throws Exception { input = whitespaceMockTokenizer("abc de fgh"); EdgeNGramTokenFilter tokenizer = new EdgeNGramTokenFilter(input, 3, 3, false); assertTokenStreamContents(tokenizer, new String[]{"abc","fgh"}, new int[]{0,7}, new int[]{3,10}); } public void testReset() throws Exception { WhitespaceTokenizer tokenizer = new WhitespaceTokenizer(); tokenizer.setReader(new StringReader("abcde")); EdgeNGramTokenFilter filter = new EdgeNGramTokenFilter(tokenizer, 1, 3, false); assertTokenStreamContents(filter, new String[]{"a","ab","abc"}, new int[]{0,0,0}, new int[]{5,5,5}); tokenizer.setReader(new StringReader("abcde")); assertTokenStreamContents(filter, new String[]{"a","ab","abc"}, new int[]{0,0,0}, new int[]{5,5,5}); } /** blast some random strings through the analyzer */ public void testRandomStrings() throws Exception { for (int i = 0; i < 10; i++) { final int min = TestUtil.nextInt(random(), 2, 10); final int max = TestUtil.nextInt(random(), min, 20); final boolean preserveOriginal = TestUtil.nextInt(random(), 0, 1) % 2 == 0; Analyzer a = new Analyzer() { @Override protected TokenStreamComponents createComponents(String fieldName) { Tokenizer tokenizer = new MockTokenizer(MockTokenizer.WHITESPACE, false); return new TokenStreamComponents(tokenizer, new EdgeNGramTokenFilter(tokenizer, min, max, preserveOriginal)); } }; checkRandomData(random(), a, 10*RANDOM_MULTIPLIER); a.close(); } } public void testEmptyTerm() throws Exception { Random random = random(); Analyzer a = new Analyzer() { @Override protected TokenStreamComponents createComponents(String fieldName) { Tokenizer tokenizer = new KeywordTokenizer(); return new TokenStreamComponents(tokenizer, new EdgeNGramTokenFilter(tokenizer, 2, 15, false)); } }; checkAnalysisConsistency(random, a, random.nextBoolean(), ""); a.close(); } public void testGraphs() throws IOException { TokenStream tk = new LetterTokenizer(); ((Tokenizer)tk).setReader(new StringReader("abc d efgh ij klmno p q")); tk = new ShingleFilter(tk); tk = new EdgeNGramTokenFilter(tk, 7, 10, false); assertTokenStreamContents(tk, new String[] { "efgh ij", "ij klmn", "ij klmno", "klmno p" }, new int[] { 6,11,11,14 }, new int[] { 13,19,19,21 }, new int[] { 3,1,0,1 }, new int[] { 2,2,2,2 }, 23 ); } public void testSupplementaryCharacters() throws IOException { for (int i = 0; i < 20; i++) { final String s = TestUtil.randomUnicodeString(random(), 10); final int codePointCount = s.codePointCount(0, s.length()); final int minGram = TestUtil.nextInt(random(), 1, 3); final int maxGram = TestUtil.nextInt(random(), minGram, 10); final boolean preserveOriginal = TestUtil.nextInt(random(), 0, 1) % 2 == 0; TokenStream tk = new KeywordTokenizer(); ((Tokenizer)tk).setReader(new StringReader(s)); tk = new EdgeNGramTokenFilter(tk, minGram, maxGram, preserveOriginal); final CharTermAttribute termAtt = tk.addAttribute(CharTermAttribute.class); final OffsetAttribute offsetAtt = tk.addAttribute(OffsetAttribute.class); tk.reset(); if (codePointCount < minGram && preserveOriginal) { assertTrue(tk.incrementToken()); assertEquals(0, offsetAtt.startOffset()); assertEquals(s.length(), offsetAtt.endOffset()); assertEquals(s, termAtt.toString()); } for (int j = minGram; j <= Math.min(codePointCount, maxGram); j++) { assertTrue(tk.incrementToken()); assertEquals(0, offsetAtt.startOffset()); assertEquals(s.length(), offsetAtt.endOffset()); final int end = Character.offsetByCodePoints(s, 0, j); assertEquals(s.substring(0, end), termAtt.toString()); } if (codePointCount > maxGram && preserveOriginal) { assertTrue(tk.incrementToken()); assertEquals(0, offsetAtt.startOffset()); assertEquals(s.length(), offsetAtt.endOffset()); assertEquals(s, termAtt.toString()); } assertFalse(tk.incrementToken()); tk.close(); } } public void testEndPositionIncrement() throws IOException { TokenStream source = whitespaceMockTokenizer("seventeen one two three four"); TokenStream input = new EdgeNGramTokenFilter(source, 8, 8, false); PositionIncrementAttribute posIncAtt = input.addAttribute(PositionIncrementAttribute.class); input.reset(); while (input.incrementToken()) {} input.end(); assertEquals(4, posIncAtt.getPositionIncrement()); } }