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A library for spelling-correction based on Levenshtein Automata.

There is a newer version: 3.0.1

package com.github.liblevenshtein.transducer;

import java.io.Serializable;
import java.util.Objects;

/**
 * {@link Position}s are used to maintain a sorted, linked-list of positions
 * within {@link com.github.liblevenshtein.transducer.State}s.  They are sorted
 * to simplify and optimize various operations on the positions (like
 * subsumption and merging-in new positions).
 * @author Dylon Edwards
 * @since 3.0.0
 */
public class Position implements Serializable {

  private static final long serialVersionUID = 1L;

  /**
   * Reference to the next node in this linked-list.  The next node may be null
   */
  private Position next = null;

  /**
   * Index of the dictionary term represented by this coordinate.
   */
  private final int termIndex;

  /**
   * Number of accumulated errors at this coordinate.
   */
  private final int numErrors;

  public Position(int termIndex, int numErrors) {
    this.termIndex = termIndex;
    this.numErrors = numErrors;
  }

  public Position next() {
    return next;
  }

  public Position next(Position next) {
    this.next = next;
    return this;
  }

  public int termIndex() {
    return termIndex;
  }

  public int numErrors() {
    return numErrors;
  }

  /**
   * Whether this position should be treated specially, such as whether it
   * represents a tranposition, merge, or split.
   * @return Whether this position should be treated specially.
   */
  public boolean isSpecial() {
    return false;
  }

  @Override
  public boolean equals(Object o) {
    if (this == o) return true;
    if (o == null || getClass() != o.getClass()) return false;
    Position position = (Position) o;
    return termIndex == position.termIndex &&
            numErrors == position.numErrors &&
            Objects.equals(next, position.next);
  }

  @Override
  public int hashCode() {
    return Objects.hash(next, termIndex, numErrors);
  }
}