CollectionsUtil.java

/*******************************************************************************
 * Copyright (c) 2011 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.jdt.internal.corext.util;

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

public class CollectionsUtil {
	/**
	 * Returns an array containing all of the elements in the given collection. This is a
	 * compile-time type-safe alternative to {@link Collection#toArray(Object[])}.
	 * 
	 * @param collection the source collection
	 * @param clazz the type of the array elements
	 * @param <A> the type of the array elements
	 * @return an array of type <code>A</code> containing all of the elements in the given
	 *         collection
	 * 
	 * @throws NullPointerException if the specified collection or class is null
	 * 
	 * @see <a href="http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=7023484">Sun bug 7023484</a>
	 */
	public static <A> A[] toArray(Collection<? extends A> collection, Class<A> clazz) {
		Object array= Array.newInstance(clazz, collection.size());
		@SuppressWarnings("unchecked")
		A[] typedArray= collection.toArray((A[]) array);
		return typedArray;
	}
}