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RocksDB fat jar that contains .so files for linux64, jnilib files
for Mac OSX, and a .dll for Windows x64. It contains the Yamcs merge operator for the Parameter Archive
// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
// This source code is licensed under both the GPLv2 (found in the
// COPYING file in the root directory) and Apache 2.0 License
// (found in the LICENSE.Apache file in the root directory).
package org.rocksdb.util;
import org.rocksdb.AbstractComparator;
import org.rocksdb.ComparatorOptions;
import java.nio.ByteBuffer;
/**
* This is a Java implementation of a Comparator for Java int
* keys.
*
* This comparator assumes keys are (at least) four bytes, so
* the caller must guarantee that in accessing other APIs in
* combination with this comparator.
*
* The performance of Comparators implemented in Java is always
* less than their C++ counterparts due to the bridging overhead,
* as such you likely don't want to use this apart from benchmarking
* or testing.
*/
public final class IntComparator extends AbstractComparator {
public IntComparator(final ComparatorOptions copt) {
super(copt);
}
@Override
public String name() {
return "rocksdb.java.IntComparator";
}
@Override
public int compare(final ByteBuffer a, final ByteBuffer b) {
return compareIntKeys(a, b);
}
/**
* Compares integer keys
* so that they are in ascending order
*
* @param a 4-bytes representing an integer key
* @param b 4-bytes representing an integer key
*
* @return negative if a < b, 0 if a == b, positive otherwise
*/
private int compareIntKeys(final ByteBuffer a, final ByteBuffer b) {
final int iA = a.getInt();
final int iB = b.getInt();
// protect against int key calculation overflow
final long diff = (long)iA - iB;
final int result;
if (diff < Integer.MIN_VALUE) {
result = Integer.MIN_VALUE;
} else if(diff > Integer.MAX_VALUE) {
result = Integer.MAX_VALUE;
} else {
result = (int)diff;
}
return result;
}
}