TreeSet descendingIterator() method in Java with Examples
The descendingIterator() method of java.util.TreeSet<E> class is used to return an iterator over the elements in this set in descending order.
Syntax:
public Iterator descendingIterator()
Return Value: This method returns an iterator over the elements in this set in descending order.
Below are the examples to illustrate the descendingIterator() method
Example 1:
// Java program to demonstrate // descendingIterator() method // for Integer value import java.util.*; public class GFG1 { public static void main(String[] argv) throws Exception { try { // create tree set object TreeSet<Integer> treeadd = new TreeSet<Integer>(); // populate the TreeSet using add() method treeadd.add( 10 ); treeadd.add( 20 ); treeadd.add( 30 ); treeadd.add( 40 ); // Print the TreeSet System.out.println( "TreeSet: " + treeadd); // create descending iterator // using descendingIterator() method Iterator<Integer> iterator = treeadd.descendingIterator(); System.out.println( "\nValues using DescendingIterator:" ); // printing the interated value while (iterator.hasNext()) { System.out.println( "Value : " + iterator.next()); } } catch (NullPointerException e) { System.out.println( "Exception thrown : " + e); } } } |
Output:
TreeSet: [10, 20, 30, 40] Values using DescendingIterator: Value : 40 Value : 30 Value : 20 Value : 10
Example 2:
// Java program to demonstrate // descendingIterator() method // for String value import java.util.*; public class GFG1 { public static void main(String[] argv) throws Exception { try { // create tree set object TreeSet<String> treeadd = new TreeSet<String>(); // populate the TreeSet using add() method treeadd.add( "A" ); treeadd.add( "B" ); treeadd.add( "C" ); treeadd.add( "D" ); // Print the TreeSet System.out.println( "TreeSet: " + treeadd); // create descending iterator // using descendingIterator() method Iterator<String> iterator = treeadd.descendingIterator(); System.out.println( "\nValues using DescendingIterator:" ); // printing the interated value while (iterator.hasNext()) { System.out.println( "Value : " + iterator.next()); } } catch (Exception e) { System.out.println( "Exception thrown : " + e); } } } |
Output:
TreeSet: [A, B, C, D] Values using DescendingIterator: Value : D Value : C Value : B Value : A
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