pregelix/pregelix-core/src/main/java/edu/uci/ics/pregelix/core/runtime/touchpoint/RawBinaryComparatorFactory.java

/*
 * Copyright 2009-2013 by The Regents of the University of California
 * Licensed 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 from
 * 
 *     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 edu.uci.ics.pregelix.core.runtime.touchpoint;

import edu.uci.ics.hyracks.api.dataflow.value.IBinaryComparator;
import edu.uci.ics.hyracks.api.dataflow.value.IBinaryComparatorFactory;

public class RawBinaryComparatorFactory implements IBinaryComparatorFactory {

    private static final long serialVersionUID = 1L;
    public static IBinaryComparatorFactory INSTANCE = new RawBinaryComparatorFactory();

    private RawBinaryComparatorFactory() {
    }

    @Override
    public IBinaryComparator createBinaryComparator() {
        return new IBinaryComparator() {

            @Override
            public int compare(byte[] b1, int s1, int l1, byte[] b2, int s2, int l2) {
                if (b1 == b2 && s1 == s2) {
                    return 0;
                }
                int commonLength = Math.min(l1, l2);
                for (int i = 0; i < commonLength; i++) {
                    if (b1[s1 + i] != b2[s2 + i]) {
                        return (b1[s1 + i] & 0xff) - (b2[s2 + i] & 0xff);
                    }
                }
                int difference = l1 - l2;
                return difference == 0 ? 0 : (difference > 0 ? 1 : -1);
            }

        };
    }
}