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 * 1. Redistributions of source code must retain the above copyright notice, this list of conditions
 * and the following disclaimer.
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package org.openjdk.jmc.common.collection;

import java.lang.reflect.Array;
import java.util.List;

/**
 * Various methods that work with arrays.
 */
public class ArrayToolkit {
	/**
	 * Filter specified indexes from an array.
	 *
	 * @param <T>
	 *            input array type
	 * @param items
	 *            input array
	 * @param excludeIndexes
	 *            Array indexes to remove. This list must be sorted.
	 * @return a new array containing values from the input array except for the excluded indexes
	 */
	@SuppressWarnings("unchecked")
	public static <T> T[] filter(T[] items, List<Integer> excludeIndexes) {
		T[] copy = (T[]) Array.newInstance(items.getClass().getComponentType(), items.length - excludeIndexes.size());
		int srcIndex = 0;
		int dstIndex = 0;
		for (Integer i : excludeIndexes) {
			int len = i - srcIndex;
			if (len > 0) {
				System.arraycopy(items, srcIndex, copy, dstIndex, len);
				dstIndex += len;
			}
			srcIndex = i + 1;
		}
		System.arraycopy(items, srcIndex, copy, dstIndex, copy.length - dstIndex);
		return copy;
	}
}
