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* Licensed to Elasticsearch under one or more contributor
* license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright
* ownership. Elasticsearch 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.elasticsearch.search.aggregations.bucket.significant.heuristics;
import org.elasticsearch.ElasticsearchParseException;
import org.elasticsearch.common.ParseFieldMatcher;
import org.elasticsearch.common.io.stream.StreamInput;
import org.elasticsearch.common.io.stream.StreamOutput;
import org.elasticsearch.common.xcontent.XContentBuilder;
import org.elasticsearch.common.xcontent.XContentParser;
import org.elasticsearch.index.query.QueryParsingException;
import org.elasticsearch.search.internal.SearchContext;
import java.io.IOException;
public class PercentageScore extends SignificanceHeuristic {
public static final PercentageScore INSTANCE = new PercentageScore();
protected static final String[] NAMES = {"percentage"};
private PercentageScore() {}
public static final SignificanceHeuristicStreams.Stream STREAM = new SignificanceHeuristicStreams.Stream() {
@Override
public SignificanceHeuristic readResult(StreamInput in) throws IOException {
return readFrom(in);
}
@Override
public String getName() {
return NAMES[0];
}
};
public static SignificanceHeuristic readFrom(StreamInput in) throws IOException {
return INSTANCE;
}
/**
* Indicates the significance of a term in a sample by determining what percentage
* of all occurrences of a term are found in the sample.
*/
@Override
public double getScore(long subsetFreq, long subsetSize, long supersetFreq, long supersetSize) {
checkFrequencyValidity(subsetFreq, subsetSize, supersetFreq, supersetSize, "PercentageScore");
if (supersetFreq == 0) {
// avoid a divide by zero issue
return 0;
}
return (double) subsetFreq / (double) supersetFreq;
}
@Override
public void writeTo(StreamOutput out) throws IOException {
out.writeString(STREAM.getName());
}
public static class PercentageScoreParser implements SignificanceHeuristicParser {
@Override
public SignificanceHeuristic parse(XContentParser parser, ParseFieldMatcher parseFieldMatcher, SearchContext context)
throws IOException, QueryParsingException {
// move to the closing bracket
if (!parser.nextToken().equals(XContentParser.Token.END_OBJECT)) {
throw new ElasticsearchParseException("failed to parse [percentage] significance heuristic. expected an empty object, but got [{}] instead", parser.currentToken());
}
return new PercentageScore();
}
@Override
public String[] getNames() {
return NAMES;
}
}
public static class PercentageScoreBuilder implements SignificanceHeuristicBuilder {
@Override
public XContentBuilder toXContent(XContentBuilder builder, Params params) throws IOException {
builder.startObject(STREAM.getName()).endObject();
return builder;
}
}
}