Java ByteBuffer Compare compareUnsigned(ByteBuffer o1, ByteBuffer o2)

Description

compare Unsigned

License

Apache License

Declaration

public static int compareUnsigned(ByteBuffer o1, ByteBuffer o2) 

Method Source Code

//package com.java2s;
/*/*from  w w  w .  j a v  a  2s . c  o  m*/
 * 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.
 */

import java.nio.ByteBuffer;

public class Main {
    public static int compareUnsigned(ByteBuffer o1, ByteBuffer o2) {
        return compareUnsigned(o1.array(), o2.array(), o1.arrayOffset() + o1.position(),
                o2.arrayOffset() + o2.position(), o1.limit() + o1.arrayOffset(), o2.limit() + o2.arrayOffset());
    }

    private static int compareUnsigned(byte[] bytes1, byte[] bytes2, int offset1, int offset2, int len1, int len2) {
        if (bytes1 == null) {
            return bytes2 == null ? 0 : -1;
        }
        if (bytes2 == null)
            return 1;

        int minLength = Math.min(len1 - offset1, len2 - offset2);
        for (int x = 0, i = offset1, j = offset2; x < minLength; x++, i++, j++) {
            if (bytes1[i] == bytes2[j])
                continue;
            // compare non-equal bytes as unsigned
            return (bytes1[i] & 0xFF) < (bytes2[j] & 0xFF) ? -1 : 1;
        }
        if ((len1 - offset1) == (len2 - offset2))
            return 0;
        else
            return ((len1 - offset1) < (len2 - offset2)) ? -1 : 1;
    }
}

Related

1. compareSubArrays(ByteBuffer bytes1, int offset1, ByteBuffer bytes2, int offset2, int length)
2. compareToP(ByteBuffer bb1, ByteBuffer bb2)