Java 类com.intellij.util.containers.Enumerator 实例源码

@Nullable
public static <T> Change buildChanges(@NotNull T[] objects1, @NotNull T[] objects2) throws FilesTooBigForDiffException {

  // Old variant of enumerator worked incorrectly with null values.
  // This check is to ensure that the corrected version does not introduce bugs.
  for (T anObjects1 : objects1) LOG.assertTrue(anObjects1 != null);
  for (T anObjects2 : objects2) LOG.assertTrue(anObjects2 != null);

  final int startShift = getStartShift(objects1, objects2);
  final int endCut = getEndCut(objects1, objects2, startShift);

  Enumerator<T> enumerator = new Enumerator<T>(objects1.length + objects2.length, ContainerUtil.<T>canonicalStrategy());
  int[] ints1 = enumerator.enumerate(objects1, startShift, endCut);
  int[] ints2 = enumerator.enumerate(objects2, startShift, endCut);
  Reindexer reindexer = new Reindexer();
  int[][] discarded = reindexer.discardUnique(ints1, ints2);
  IntLCS intLCS = new IntLCS(discarded[0], discarded[1]);
  intLCS.execute();
  ChangeBuilder builder = new ChangeBuilder(startShift);
  reindexer.reindex(intLCS.getPaths(), builder);
  return builder.getFirstChange();
}

@Nullable
public static <T> Change buildChanges(@Nonnull T[] objects1, @Nonnull T[] objects2) throws FilesTooBigForDiffException {

  // Old variant of enumerator worked incorrectly with null values.
  // This check is to ensure that the corrected version does not introduce bugs.
  for (T anObjects1 : objects1) LOG.assertTrue(anObjects1 != null);
  for (T anObjects2 : objects2) LOG.assertTrue(anObjects2 != null);

  final int startShift = getStartShift(objects1, objects2);
  final int endCut = getEndCut(objects1, objects2, startShift);

  Ref<Change> changeRef = doBuildChangesFast(objects1.length, objects2.length, startShift, endCut);
  if (changeRef != null) return changeRef.get();

  int trimmedLength = objects1.length + objects2.length - 2 * startShift - 2 * endCut;
  Enumerator<T> enumerator = new Enumerator<T>(trimmedLength, ContainerUtil.<T>canonicalStrategy());
  int[] ints1 = enumerator.enumerate(objects1, startShift, endCut);
  int[] ints2 = enumerator.enumerate(objects2, startShift, endCut);
  return doBuildChanges(ints1, ints2, new ChangeBuilder(startShift));
}