package htsjdk.samtools;
/**
* The MIT License
* <p/>
* Copyright (c) 2014 The Broad Institute
* <p/>
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
* <p/>
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
* <p/>
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
import java.util.Comparator;
/**
* Provides ordering based on SAM header records' attribute values. Provide the list of attributes to use
* in the comparison to the constructor. Null attribute values (i.e., those attributes not present in the
* record) sort behind those that have values.
*/
public class SAMHeaderRecordComparator<T extends AbstractSAMHeaderRecord> implements Comparator<T> {
private final String[] attributes;
public SAMHeaderRecordComparator(final String... attributes) {
this.attributes = attributes;
}
@Override
public int compare(final T left, final T right) {
for (final String attribute : attributes) {
final String leftValue = left.getAttribute(attribute);
final String rightValue = right.getAttribute(attribute);
if (leftValue == null) {
// Fastest comparison possible; two empty values are
// equivalent, so move along to the next attribute
if (rightValue == null) continue;
// Otherwise left < right, since right has a value
else return -1;
}
// left is not null; if right is, left > right
if (rightValue == null) return 1;
final int compare = leftValue.compareTo(rightValue);
if (compare != 0) return compare;
}
return 0;
}
}