org.elasticsearch.index.codec.postingsformat.MemoryPostingsFormatProvider Maven / Gradle / Ivy
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* file to you under the Apache License, Version 2.0 (the
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*
* http://www.apache.org/licenses/LICENSE-2.0
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package org.elasticsearch.index.codec.postingsformat;
import org.apache.lucene.codecs.PostingsFormat;
import org.apache.lucene.codecs.memory.MemoryPostingsFormat;
import org.apache.lucene.util.packed.PackedInts;
import org.elasticsearch.common.inject.Inject;
import org.elasticsearch.common.inject.assistedinject.Assisted;
import org.elasticsearch.common.settings.Settings;
/**
* A {@link PostingsFormatProvider} for Lucenes {@link MemoryPostingsFormat}.
* This postings format offers the following parameters:
*
* - pack_fst:
true iff the in memory structure should
* be packed once its build. Packed will reduce the size for the data-structure
* in memory but requires more memory during building. Default is false
*
* - acceptable_overhead_ratio: the compression overhead used to
* compress internal structures. See {@link PackedInts} for details. Default is {@value PackedInts#DEFAULT}
*
*/
public class MemoryPostingsFormatProvider extends AbstractPostingsFormatProvider {
private final boolean packFst;
private final float acceptableOverheadRatio;
private final MemoryPostingsFormat postingsFormat;
@Inject
public MemoryPostingsFormatProvider(@Assisted String name, @Assisted Settings postingsFormatSettings) {
super(name);
this.packFst = postingsFormatSettings.getAsBoolean("pack_fst", false);
this.acceptableOverheadRatio = postingsFormatSettings.getAsFloat("acceptable_overhead_ratio", PackedInts.DEFAULT);
// TODO this should really be an ENUM?
this.postingsFormat = new MemoryPostingsFormat(packFst, acceptableOverheadRatio);
}
public boolean packFst() {
return packFst;
}
public float acceptableOverheadRatio() {
return acceptableOverheadRatio;
}
@Override
public PostingsFormat get() {
return postingsFormat;
}
}