blob: 1ca7fdd9d4e0d8a0f5104a6e4106fc7a94783c3a [file] [log] [blame]
/*
* Copyright (C) 2010, Google Inc.
* and other copyright owners as documented in the project's IP log.
*
* This program and the accompanying materials are made available
* under the terms of the Eclipse Distribution License v1.0 which
* accompanies this distribution, is reproduced below, and is
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package org.eclipse.jgit.diff;
/**
* Wrap another comparator for use with {@link HashedSequence}.
* <p>
* This comparator acts as a proxy for the real comparator, evaluating the
* cached hash code before testing the underlying comparator's equality.
* Comparators of this type must be used with a {@link HashedSequence}.
* <p>
* To construct an instance of this type use {@link HashedSequencePair}.
*
* @param <S>
* the base sequence type.
*/
public final class HashedSequenceComparator<S extends Sequence> extends
SequenceComparator<HashedSequence<S>> {
private final SequenceComparator<? super S> cmp;
HashedSequenceComparator(SequenceComparator<? super S> cmp) {
this.cmp = cmp;
}
@Override
public boolean equals(HashedSequence<S> a, int ai, //
HashedSequence<S> b, int bi) {
return a.hashes[ai] == b.hashes[bi]
&& cmp.equals(a.base, ai, b.base, bi);
}
@Override
public int hash(HashedSequence<S> seq, int ptr) {
return seq.hashes[ptr];
}
}