Treat an Enumeration as an Iterable : Enumerator « Collections Data Structure « Java

Treat an Enumeration as an Iterable

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import java.util.Enumeration;
import java.util.Iterator;

 * @since 4.37
 * @author Jaroslav Tulach

public class Utils {
   * Treat an {@link Enumeration} as an {@link Iterable} so it can be used in an enhanced for-loop.
   * Bear in mind that the enumeration is "consumed" by the loop and so should be used only once.
   * Generally it is best to put the code which obtains the enumeration inside the loop header.
   * <div class="nonnormative">
   * <p>Example of correct usage:</p>
   * <pre>
   * ClassLoader loader = ...;
   * String name = ...;
   * for (URL resource : NbCollections.iterable(loader.{@link ClassLoader#getResources getResources}(name))) {
   *     // ...
   * }
   * </pre>
   * </div>
   * @param enumeration an enumeration
   * @return an iterable wrapper which will traverse the enumeration once
   *         ({@link Iterator#remove} is not supported)
   * @throws NullPointerException if the enumeration is null
   * @see <a href="">Java bug #6349852</a>
   * @since org.openide.util 7.5
  public static <E> Iterable<E> iterable(final Enumeration<E> enumeration) {
      if (enumeration == null) {
          throw new NullPointerException();
      return new Iterable<E>() {
          public Iterator<E> iterator() {
              return new Iterator<E>() {
                  public boolean hasNext() {
                      return enumeration.hasMoreElements();
                  public E next() {
                      return enumeration.nextElement();
                  public void remove() {
                      throw new UnsupportedOperationException();



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11.Concatenates the content of two enumerations into one.
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14.For each element of the input enumeration asks the Processor to provide a replacement