/*
* Licensed to the Apache Software Foundation (ASF) under one or more contributor license
* agreements. See the NOTICE file distributed with this work for additional information regarding
* copyright ownership. The ASF licenses this file to You under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the License. You may obtain a
* copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software distributed under the License
* is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
* or implied. See the License for the specific language governing permissions and limitations under
* the License.
*/
package org.apache.geode.internal.cache.persistence.query.mock;
import java.util.Comparator;
import org.apache.geode.internal.cache.CachedDeserializable;
import org.apache.geode.internal.cache.EntryEventImpl;
/**
* Compare the serialized form of two objects.
*
* Note that this does not do lexigraphic order, or really any useful order. It's only guaranteed to
* return 0 if the bytes are equal, and satisfy all the transitivity and communitivity properties of
* compare.
*
*/
public class ByteComparator implements Comparator<Object> {
public static final byte[] MIN_BYTES = new byte[0];
public static final byte[] MAX_BYTES = new byte[0];
@Override
public int compare(Object o1, Object o2) {
byte[] o1Bytes = getBytes(o1);
byte[] o2Bytes = getBytes(o2);
if (o1Bytes == o2Bytes) {
return 0;
}
if (o1Bytes == MIN_BYTES) {
return -1;
}
if (o2Bytes == MIN_BYTES) {
return 1;
}
if (o1Bytes == MAX_BYTES) {
return 1;
}
if (o2Bytes == MAX_BYTES) {
return -1;
}
for (int i = 0; i < o1Bytes.length; i++) {
if (i > o2Bytes.length) {
return 1;
} else {
int result = o1Bytes[i] - o2Bytes[i];
if (result != 0) {
return result;
}
}
}
return o2Bytes.length > o1Bytes.length ? 1 : 0;
}
private byte[] getBytes(Object o) {
if (o instanceof byte[]) {
return (byte[]) o;
}
if (o instanceof CachedDeserializable) {
return ((CachedDeserializable) o).getSerializedValue();
} else {
return EntryEventImpl.serialize(o);
}
}
}