java tree set code example

Example 1: TreeSet in java

// java treeset example
import java.util.Iterator;
import java.util.TreeSet;
public class TreeSetExamples
{
   public static void main(String[] args)
   {
      TreeSet<String> ts = new TreeSet<String>();
      ts.add("red");
      ts.add("blue");
      ts.add("green");
      ts.add("red");
      Iterator<String> iterate = ts.iterator();
      while(iterate.hasNext())
      {
         System.out.println(iterate.next());
      }
   }
}

Example 2: java treeset

import java.util.*;

// Declare the variable using the interface of the object for flexibility.
// Non-primative data types only.
Set<String> movies = new TreeSet<String>();

movies.add(E);
// TreeSet will be sorted by element.
// Work with any comparable object.

movies.add("The Shining");
movies.add("Dawn of the Dead");
movies.add("Zombieland");

Example 3: TreeSet

// par défaut
TreeSet ensemble = new TreeSet();
// comparateur
Comparator comparateur = new Comparateur();
TreeSet ensemble = new TreeSet(comparateur);

// classe Comparateur implémentant l'interface Comparator
public class Comparateur implements Comparator {
  public int compare(Object obj1, Object obj2){
    return ((Comparable)obj2).compareTo(obj1);
  }
  public boolean equals(Object obj){
    return this.equals(obj);
  }
}

Example 4: treeset

TreeSet: Can contain only unique values and it is sorted in ascending order
TreeMap: Can contain only unique keys and keys are sorted in ascending order.

Example 5: treeset in java

- TreeSet sorts the order and don't accept null