package javaapplication1;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.Iterator;
import java.util.List;
public class JavaApplication1 {
public static void main(String[] args) {
List<String> list = new ArrayList<>();
list.add("aaa");
list.add("bbb");
list.add("ccc");
list.add("ddd");
System.out.println(list.get(0));
System.out.println(list.get(1));
Collection<String> unmodifiable = Collections.unmodifiableCollection(list);
Iterator<String> iterator = unmodifiable.iterator();
System.out.println();
while (iterator.hasNext())
System.out.println(iterator.next());
}
}
/*
run:
aaa
bbb
aaa
bbb
ccc
ddd
*/