How to avoid java.lang.outofmemoryexception

There are primarily 3 ways I can think of to traverse a java.util.List:

• Using a traditional for loop;
  
• Using a simplified for loop, or "foreach" statement in JDK 5 ;
  
• Using java.util.Iterator
  

 public static void traverse(List data) {
    System.out.println("Using simplified for loop/foreach:");
    for(Object obj : data) {
        System.out.println(obj);
    }

    System.out.println("Using for loop:");
    for(int i = 0, n = data.size(); i < n; i++) {
        System.out.println(data.get(i));
    }

    System.out.println("Using Iterator:");
    for(Iterator it = data.iterator(); it.hasNext();) {
        System.out.println(it.next());
    }
}