Entity.java

package com.linkedin.thirdeye.rootcause;

import java.util.Comparator;


/**
 * An entity represents a node in the knowledge graph traversed to identify potential root causes.
 * The URN represents a unique identifier (with a hierarchical namespace) and the score identifies
 * the relative importance to other entities given a specific context.
 * In the user-specified search context, the score represents the subjective importance of the
 * entity as determined by the user. In the execution context and the pipeline results the score
 * represents the relative importance of entities associated with the search context as determined
 * by individual pipelines and the aggregator.
 *
 * <br/><b>NOTE:</b> a subclass of {@code Entity} may be returned by pipelines in order to pass
 * along transient meta-data for individual entities.
 *
 * <br/><b>NOTE:</b> due to the potentially vast number of nodes in the knowledge graph there is no
 * centralized repository of valid URNs.
 */
public class Entity {
  private final String urn;
  private final double score;

  public static final Comparator<Entity> HIGHEST_SCORE_FIRST = new Comparator<Entity>() {
    @Override
    public int compare(Entity o1, Entity o2) {
      return -1 * Double.compare(o1.score, o2.score);
    }
  };

  public Entity(String urn, double score) {
    this.urn = urn;
    this.score = score;
  }

  public String getUrn() {
    return urn;
  }

  public double getScore() {
    return score;
  }

  public Entity withScore(double score) {
    return new Entity(this.urn, score);
  }

  @Override
  public String toString() {
    return String.format("%s(urn=%s, score=%.3f)", getClass().getSimpleName(), this.urn, this.score);
  }
}