Treat an Iterator as an Iterable : Iterator « Collections « Java Tutorial






  1. Java Tutorial
  2. Collections
  3. Iterator
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import java.io.Serializable;
import java.util.AbstractMap;
import java.util.AbstractSet;
import java.util.Collection;
import java.util.Enumeration;
import java.util.Iterator;
import java.util.Map;
import java.util.NoSuchElementException;
import java.util.Set;

/**
 * @since 4.37
 * @author Jaroslav Tulach
 */


public class Utils {
  /**
   * Treat an {@link Iterator} as an {@link Iterable} so it can be used in an enhanced for-loop.
   * Bear in mind that the iterator is "consumed" by the loop and so should be used only once.
   * Generally it is best to put the code which obtains the iterator inside the loop header.
   * <div class="nonnormative">
   * Example of correct usage:
   * <pre>
   * String text = ...;
   * for (String token : NbCollections.iterable(new {@link java.util.Scanner}(text))) {
   *     // ...
   * }
   * </pre>
   * </div>
   * @param iterator an iterator
   * @return an iterable wrapper which will traverse the iterator once
   * @throws NullPointerException if the iterator is null
   * @see <a href="http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=6312085">Java bug #6312085</a>
   * @see <a href="http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=6360734">Java bug #6360734</a>
   * @see <a href="http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4988624">Java bug #4988624</a>
   * @since org.openide.util 7.5
   */
  public static <E> Iterable<E> iterable(final Iterator<E> iterator) {
      if (iterator == null) {
          throw new NullPointerException();
      }
      return new Iterable<E>() {
          public Iterator<E> iterator() {
              return iterator;
          }
      };
  }

}








9.37.Iterator
9.37.1.Use Iterator to loop through ArrayList
9.37.2.Use Iterator to loop through the HashMap class
9.37.3.Iterate through a Collection using Java Iterator
9.37.4.Traverse through ArrayList in forward direction using Java ListIterator
9.37.5.Traverse through ArrayList in reverse direction using Java ListIterator
9.37.6.Iterate a Collection and remove an item (Exception, wrong version)
9.37.7.Remove an element from Collection using Java Iterator
9.37.8.Iterator from LinkedList
9.37.9.Iterate through elements of Java LinkedList using Iterator
9.37.10.An Iterator that wraps a number of Iterators
9.37.11.Array Iterator
9.37.12.Create singleton Iterator
9.37.13.Cyclic Iteration
9.37.14.Iterator Union of Iterators
9.37.15.Iterator Utils
9.37.16.Iterator class for sparse values in an array.
9.37.17.Iterator class for values contained in an array range.
9.37.18.Sorted Iterator
9.37.19.Treat an Iterator as an Iterable
9.37.20.An Iterator that returns the elements of a specified array, or other iterators etc.
9.37.21.An Iterator wrapper for an Enumeration.
9.37.22.An Iterator wrapper for an Object[], allow us to deal with all array like structures in a consistent manner.
9.37.23.An iterator that breaks text into lines. The result is equal to BufferedReader.readLine().
9.37.24.Gets the child of the specified element having the specified unique name
9.37.25.Implements an java.util.Iterator over any array
9.37.26.Protects an given iterator by preventing calls to remove().
9.37.27.Returns an iterator over the children of the given element with the given tag name
9.37.28.Use an Iterator to cycle through a collection in the forward direction.
9.37.29.This constructs an Iterator over each day in a date range defined by a focus date and range style.