collectioncopy.java

高质量Java程序设计 源代码

package net.betterjava.design.collection.deepcopy;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Iterator;
import java.util.List;
import net.betterjava.design.collection.shadowcopy.Visitor;

//Collections.copy() is a shadow copy
public class CollectionCopy {

	private static void printList(List list) {
		Iterator it = list.iterator();
		while (it.hasNext()) {
			System.out.println(it.next());
		}

	}

	public static void main(String[] args) {
		ArrayList list = new ArrayList();
		list.add(new Visitor("Alex", "Fa Hua Zhen Road"));
		list.add(new Visitor("Field", "Xiao Mu Qiao Road"));
		printList(list);

		ArrayList copyList = new ArrayList(list.size());
		copyList.add(null);
		copyList.add(null);
		Collections.copy(copyList, list);
		((Visitor) copyList.get(0)).setAddress("Fan Yu Road");
		printList(list);
	}
}