/*
* 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;
import java.util.HashMap;
import java.util.Map;
import java.util.Random;
import org.apache.lucene.util.LuceneTestCase;
import org.apache.lucene.util.automaton.CharacterRunAutomaton;
/**
* Analyzer for testing
* <p>
* This analyzer is a replacement for Whitespace/Simple/KeywordAnalyzers
* for unit tests. If you are testing a custom component such as a queryparser
* or analyzer-wrapper that consumes analysis streams, it's a great idea to test
* it with this analyzer instead. MockAnalyzer has the following behavior:
* <ul>
* <li>By default, the assertions in {@link MockTokenizer} are turned on for extra
* checks that the consumer is consuming properly. These checks can be disabled
* with {@link #setEnableChecks(boolean)}.
* <li>Payload data is randomly injected into the stream for more thorough testing
* of payloads.
* </ul>
* @see MockTokenizer
*/
public final class MockAnalyzer extends Analyzer {
private final CharacterRunAutomaton runAutomaton;
private final boolean lowerCase;
private final CharacterRunAutomaton filter;
private int positionIncrementGap;
private Integer offsetGap;
private final Random random;
private Map<String,Integer> previousMappings = new HashMap<>();
private boolean enableChecks = true;
private int maxTokenLength = MockTokenizer.DEFAULT_MAX_TOKEN_LENGTH;
/**
* Creates a new MockAnalyzer.
*
* @param random Random for payloads behavior
* @param runAutomaton DFA describing how tokenization should happen (e.g. [a-zA-Z]+)
* @param lowerCase true if the tokenizer should lowercase terms
* @param filter DFA describing how terms should be filtered (set of stopwords, etc)
*/
public MockAnalyzer(Random random, CharacterRunAutomaton runAutomaton, boolean lowerCase, CharacterRunAutomaton filter) {
super(PER_FIELD_REUSE_STRATEGY);
// TODO: this should be solved in a different way; Random should not be shared (!).
this.random = new Random(random.nextLong());
this.runAutomaton = runAutomaton;
this.lowerCase = lowerCase;
this.filter = filter;
}
/**
* Calls {@link #MockAnalyzer(Random, CharacterRunAutomaton, boolean, CharacterRunAutomaton)
* MockAnalyzer(random, runAutomaton, lowerCase, MockTokenFilter.EMPTY_STOPSET, false}).
*/
public MockAnalyzer(Random random, CharacterRunAutomaton runAutomaton, boolean lowerCase) {
this(random, runAutomaton, lowerCase, MockTokenFilter.EMPTY_STOPSET);
}
/**
* Create a Whitespace-lowercasing analyzer with no stopwords removal.
* <p>
* Calls {@link #MockAnalyzer(Random, CharacterRunAutomaton, boolean, CharacterRunAutomaton)
* MockAnalyzer(random, MockTokenizer.WHITESPACE, true, MockTokenFilter.EMPTY_STOPSET, false}).
*/
public MockAnalyzer(Random random) {
this(random, MockTokenizer.WHITESPACE, true);
}
@Override
public TokenStreamComponents createComponents(String fieldName) {
MockTokenizer tokenizer = new MockTokenizer(runAutomaton, lowerCase, maxTokenLength);
tokenizer.setEnableChecks(enableChecks);
MockTokenFilter filt = new MockTokenFilter(tokenizer, filter);
return new TokenStreamComponents(tokenizer, maybePayload(filt, fieldName));
}
@Override
protected TokenStream normalize(String fieldName, TokenStream in) {
TokenStream result = in;
if (lowerCase) {
result = new MockLowerCaseFilter(result);
}
return result;
}
private synchronized TokenFilter maybePayload(TokenFilter stream, String fieldName) {
Integer val = previousMappings.get(fieldName);
if (val == null) {
val = -1; // no payloads
if (LuceneTestCase.rarely(random)) {
switch(random.nextInt(3)) {
case 0: val = -1; // no payloads
break;
case 1: val = Integer.MAX_VALUE; // variable length payload
break;
case 2: val = random.nextInt(12); // fixed length payload
break;
}
}
if (LuceneTestCase.VERBOSE) {
if (val == Integer.MAX_VALUE) {
System.out.println("MockAnalyzer: field=" + fieldName + " gets variable length payloads");
} else if (val != -1) {
System.out.println("MockAnalyzer: field=" + fieldName + " gets fixed length=" + val + " payloads");
}
}
previousMappings.put(fieldName, val); // save it so we are consistent for this field
}
if (val == -1)
return stream;
else if (val == Integer.MAX_VALUE)
return new MockVariableLengthPayloadFilter(random, stream);
else
return new MockFixedLengthPayloadFilter(random, stream, val);
}
public void setPositionIncrementGap(int positionIncrementGap){
this.positionIncrementGap = positionIncrementGap;
}
@Override
public int getPositionIncrementGap(String fieldName){
return positionIncrementGap;
}
/**
* Set a new offset gap which will then be added to the offset when several fields with the same name are indexed
* @param offsetGap The offset gap that should be used.
*/
public void setOffsetGap(int offsetGap){
this.offsetGap = offsetGap;
}
/**
* Get the offset gap between tokens in fields if several fields with the same name were added.
* @param fieldName Currently not used, the same offset gap is returned for each field.
*/
@Override
public int getOffsetGap(String fieldName){
return offsetGap == null ? super.getOffsetGap(fieldName) : offsetGap;
}
/**
* Toggle consumer workflow checking: if your test consumes tokenstreams normally you
* should leave this enabled.
*/
public void setEnableChecks(boolean enableChecks) {
this.enableChecks = enableChecks;
}
/**
* Toggle maxTokenLength for MockTokenizer
*/
public void setMaxTokenLength(int length) {
this.maxTokenLength = length;
}
}