org.elasticsearch.index.fielddata.fieldcomparator.NestedWrappableComparator Maven / Gradle / Ivy

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 *    http://www.apache.org/licenses/LICENSE-2.0
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package org.elasticsearch.index.fielddata.fieldcomparator;

import org.apache.lucene.search.FieldComparator;

/** Base comparator which allows for nested sorting. */
public abstract class NestedWrappableComparator extends FieldComparator {

    /**
     * Assigns the underlying missing value to the specified slot, if the actual implementation supports missing value.
     *
     * @param slot The slot to assign the the missing value to.
     */
    public abstract void missing(int slot);

    /**
     * Compares the missing value to the bottom.
     *
     * @return any N < 0 if the bottom value is not competitive with the missing value, any N > 0 if the
     * bottom value is competitive with the missing value and 0 if they are equal.
     */
    public abstract int compareBottomMissing();

}