org.eclipse.jgit.diff.HashedSequenceComparator Maven / Gradle / Ivy
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package org.eclipse.jgit.diff;
/**
* Wrap another comparator for use with {@link HashedSequence}.
*
* 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}.
*
* To construct an instance of this type use {@link HashedSequencePair}.
*
* @param
* the base sequence type.
*/
public final class HashedSequenceComparator extends
SequenceComparator> {
private final SequenceComparator cmp;
HashedSequenceComparator(SequenceComparator cmp) {
this.cmp = cmp;
}
@Override
public boolean equals(HashedSequence a, int ai, //
HashedSequence b, int bi) {
return a.hashes[ai] == b.hashes[bi]
&& cmp.equals(a.base, ai, b.base, bi);
}
@Override
public int hash(HashedSequence seq, int ptr) {
return seq.hashes[ptr];
}
}