treeset java descending order using comparator
import java.util.Iterator;
import java.util.NavigableSet;
import java.util.TreeSet;
public class TreeSetDescendingSetMethodExample
{
public static void main(String[] args)
{
try
{
TreeSet<String> ts = new TreeSet<String>();
ts.add("Apple");
ts.add("Banana");
ts.add("Cherry");
ts.add("Dragon Fruit");
System.out.println("TreeSet: " + ts);
// reverse order view of element using descendingSet() method
NavigableSet<String> ns = ts.descendingSet();
Iterator<String> iterate = ns.iterator();
System.out.println("Values using descendingSet() method: ");
while(iterate.hasNext())
{
System.out.println(iterate.next());
}
}
catch(NullPointerException ex)
{
System.out.println("Exception: " + ex);
}
}
}
//To sort a treeset in descending order just use the descendingSet() method
import java.util.TreeSet;
public class Main {
public static void main(String[] args) {
TreeSet<Object> treeSet = new TreeSet<Object>();
treeSet.add(45);
treeSet.add(15);
treeSet.add(99);
treeSet.add(70);
treeSet.add(65);
treeSet.add(30);
treeSet.add(10);
treeSet.add(60);
treeSet.add(80);
System.out.println("TreeSet\n" + treeSet);
TreeSet<Object> res = (TreeSet<Object>)treeSet.descendingSet();
System.out.println("TreeSet after sorting in descending order\n" + res);
}
}