org.apache.tika.eval.textstats.TopNTokens Maven / Gradle / Ivy
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* 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
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package org.apache.tika.eval.textstats;
import java.util.Map;
import org.apache.commons.lang3.mutable.MutableInt;
import org.apache.commons.math3.stat.descriptive.SummaryStatistics;
import org.apache.tika.eval.tokens.TokenCounts;
import org.apache.tika.eval.tokens.TokenIntPair;
public class TopNTokens implements TokenCountStatsCalculator {
private final int topN;
public TopNTokens(int topN) {
this.topN = topN;
}
@Override
public TokenIntPair[] calculate(TokenCounts tokenCounts) {
TokenCountPriorityQueue queue = new TokenCountPriorityQueue(topN);
SummaryStatistics summaryStatistics = new SummaryStatistics();
for (Map.Entry e : tokenCounts.getTokens().entrySet()) {
String token = e.getKey();
int termFreq = e.getValue().intValue();
if (queue.top() == null || queue.size() < topN ||
termFreq >= queue.top().getValue()) {
queue.insertWithOverflow(new TokenIntPair(token, termFreq));
}
}
return queue.getArray();
}
}