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Artifact with collection definitions and collections.
There is a newer version: 1.1.6
// /////////////////////////////////////////////////////////////////////////////
// REFCODES.ORG
// =============================================================================
// This code is copyright (c) by Siegfried Steiner, Munich, Germany and licensed
// under the following (see "http://en.wikipedia.org/wiki/Multi-licensing")
// licenses:
// =============================================================================
// GNU General Public License, v3.0 ("http://www.gnu.org/licenses/gpl-3.0.html")
// together with the GPL linking exception applied; as being applied by the GNU
// Classpath ("http://www.gnu.org/software/classpath/license.html")
// =============================================================================
// Apache License, v2.0 ("http://www.apache.org/licenses/LICENSE-2.0")
// =============================================================================
// Please contact the copyright holding author(s) of the software artifacts in
// question for licensing issues not being covered by the above listed licenses,
// also regarding commercial licensing models or regarding the compatibility
// with other open source licenses.
// /////////////////////////////////////////////////////////////////////////////

package org.refcodes.collection;

import java.util.ArrayList;
import java.util.Collection;
import java.util.Iterator;
import java.util.List;

public final class CollectionUtility {

	// /////////////////////////////////////////////////////////////////////////
	// CONSTRUCTORS:
	// /////////////////////////////////////////////////////////////////////////

	/**
	 * Private empty constructor to prevent instantiation as of being a utility
	 * with just static public methods.
	 */
	private CollectionUtility() {}

	// /////////////////////////////////////////////////////////////////////////
	// METHODS:
	// /////////////////////////////////////////////////////////////////////////

	/**
	 * Creates a new list and copies the content of the iterator into the list.
	 * Caution: The iterator is empty afterwards! You may easily retrieve an
	 * iterator with the same elements as the provided one by using the method
	 * 'iterator()' of the returned list.
	 * 
	 * @param anIterator Description of the Parameter
	 * @return Description of the Return Value
	 */
	public static  List toArrayList( Iterator anIterator ) {
		List theList = new ArrayList();
		if ( anIterator != null ) while ( anIterator.hasNext() )
			theList.add( anIterator.next() );
		return theList;
	}

	/**
	 * Returns the max length of the arrays passed to this method.
	 * 
	 * @param aObjects The arrays of which the length of the one with the most
	 *        elements is returned.
	 * 
	 * @return The max length of elements found in the provided arrays or -1 if
	 *         all the arrays were null.
	 */
	@SafeVarargs
	public static  int toMaxLength( T[]... aObjects ) {
		int theMaxLength = -1;
		for ( Object[] eArray : aObjects ) {
			if ( eArray != null && eArray.length > theMaxLength ) {
				theMaxLength = eArray.length;
			}
		}
		return theMaxLength;
	}

	/**
	 * Returns the max size of the collections passed to this method.
	 * 
	 * @param aCollections The collections of which the size of the one with the
	 *        most elements is returned.
	 * 
	 * @return The max length of elements found in the provided collections or
	 *         -1 if all the collections were null.
	 */
	public static int toMaxLength( Collection... aCollections ) {
		int theMaxLength = -1;
		for ( Collection eCollection : aCollections ) {
			if ( eCollection != null && eCollection.size() > theMaxLength ) {
				theMaxLength = eCollection.size();
			}
		}
		return theMaxLength;
	}

	// /////////////////////////////////////////////////////////////////////////
	// CSV:
	// /////////////////////////////////////////////////////////////////////////


}