iterators

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java

Java Collections

java

What will be the result of the code: import java.util.Arrays; import java.util.Iterator; import java.util.List; public class Test { public static void main(String[] args) { String[] str = new String[] { "1", "2", "3" }; List list = Arrays.asList(str); for (Iterator iterator = list.iterator(); iterator.hasNext();) { Object object = (Object) iterator.next(); iterator.remove(); } System.out.println(list.size()); } }

java

What happens if the following code is executed? import java.util.ArrayList; import java.util.Collections; import java.util.Iterator; import java.util.List; public class Test<T> implements Iterable<T>{ // 1 private List<T> list = new ArrayList<T>(); public void addList(T... ts) { Collections.addAll(list, ts); } public static void main(String... args) { Test<String> t = new Test<String>(); t.addList("Hello", "world", "!"); for (String str : t) { // 2 System.out.print(str + " "); } } public Iterator<T> iterator() { return new Iterator() { // 3 private int index = 0; public boolean hasNext() { return index < list.size(); } public Object next() { return list.get(index++); } public void remove() { throw new UnsupportedOperationException("unsupported operation"); } }; } }

java

What happens when you run the following code? import java.util.ArrayList; import java.util.Collections; import java.util.Iterator; import java.util.List; public class Test<T> implements Iterator<T>{ // 1 private List<T> list = new ArrayList<T>(); // 2 public void addList(T... ts) { Collections.addAll(list, ts); // 3 } public static void main(String args[]) { Test<String> t = new Test<String>(); t.addList("Hello world"); for (String str : t) { // 4 System.out.print(str + " "); } } public Iterator<T> iterator() { return list.iterator(); } }