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/*
 * Copyright (C) 2004-2014 Volker Bergmann ([email protected]).
 * All rights reserved.
 *
 * 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 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.databene.commons.comparator;

import org.databene.commons.ComparableComparator;

import java.util.Comparator;

/**
 * Compares two arrays by the first  array elements with a Comparator.

 * 

 * Created: 22.05.2007 07:07:17
 * @since 0.1
 * @author Volker Bergmann
 */
public class ArrayComparator implements Comparator {

    private Comparator elementComparator;

    @SuppressWarnings({ "unchecked", "rawtypes" })
    public ArrayComparator() {
        this(new ComparableComparator());
    }

    public ArrayComparator(Comparator elementComparator) {
        this.elementComparator = elementComparator;
    }

    @Override
	public int compare(E[] array1, E[] array2) {
    	if (array1 == null)
    		return (array2 == null ? 0 : -1);
    	if (array2 == null)
    		return 1;
        // iterate through the elements and compara them one by one
        int minLength = Math.min(array1.length, array2.length);
        for (int i = 0; i < minLength; i++) {
            int elementComparison = elementComparator.compare(array1[i], array2[i]);
            // if element #i differs then return the difference
            if (elementComparison != 0)
                return elementComparison;
        }
        // All elements from 0 to minLength are equals - return the longer array as greater
        if (array1.length < array2.length)
            return -1;
        else if (array1.length > array2.length)
            return 1;
        else // the arrays have equal size and equal elements
            return 0;
    }
    
}