/*

 * Copyright (c) 1999, 2013, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

package com.sun.tools.javac.util;

import java.lang.reflect.Array;

/** <p><b>This is NOT part of any supported API.

 *  If you write code that depends on this, you do so at your own risk.

 *  This code and its internal interfaces are subject to change or

 *  deletion without notice.</b>

 */

public class ArrayUtils {

    private static int calculateNewLength(int currentLength, int maxIndex) {

        while (currentLength < maxIndex + 1)

            currentLength = currentLength * 2;

        return currentLength;

    }

    public static <T> T[] ensureCapacity(T[] array, int maxIndex) {

        if (maxIndex < array.length) {

            return array;

        } else {

            int newLength = calculateNewLength(array.length, maxIndex);

            @SuppressWarnings("unchecked")

            T[] result = (T[]) Array.newInstance(array.getClass().getComponentType(), newLength);

            System.arraycopy(array, 0, result, 0, array.length);

            return result;

        }

    }

    public static byte[] ensureCapacity(byte[] array, int maxIndex) {

        if (maxIndex < array.length) {

            return array;

        } else {

            int newLength = calculateNewLength(array.length, maxIndex);

            byte[] result = new byte[newLength];

            System.arraycopy(array, 0, result, 0, array.length);

            return result;

        }

    }

    public static char[] ensureCapacity(char[] array, int maxIndex) {

        if (maxIndex < array.length) {

            return array;

        } else {

            int newLength = calculateNewLength(array.length, maxIndex);

            char[] result = new char[newLength];

            System.arraycopy(array, 0, result, 0, array.length);

            return result;

        }

    }

    public static int[] ensureCapacity(int[] array, int maxIndex) {

        if (maxIndex < array.length) {

            return array;

        } else {

            int newLength = calculateNewLength(array.length, maxIndex);

            int[] result = new int[newLength];

            System.arraycopy(array, 0, result, 0, array.length);

            return result;

        }

    }

}