import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
public class Main {
public static void main(String[] argv) {
List collection = new ArrayList();
// For a set or list
for (Iterator it = collection.iterator(); it.hasNext();) {
Object element = it.next();
}
Map map = new HashMap();
// For keys of a map
for (Iterator it = map.keySet().iterator(); it.hasNext();) {
Object key = it.next();
}
// For values of a map
for (Iterator it = map.values().iterator(); it.hasNext();) {
Object value = it.next();
}
// For both the keys and values of a map
for (Iterator it = map.entrySet().iterator(); it.hasNext();) {
Map.Entry entry = (Map.Entry) it.next();
Object key = entry.getKey();
Object value = entry.getValue();
}
}
}