Remove all elements from Java TreeSet example
- /*
- Remove all elements from Java TreeSet example
- This Java Example shows how to remove all elements contained in Java TreeSet
- or clear TreeSet object using clear or removeAll methods. It also shows how
- to check whether TreeSet object is empty or not using isEmpty method.
- */
- import java.util.TreeSet;
- public class RemoveAllElementsFromTreeSetExample {
- public static void main(String[] args) {
- //create object of TreeSet
- TreeSet tSet = new TreeSet();
- //add elements to TreeSet object
- tSet.add(new Integer("1"));
- tSet.add(new Integer("2"));
- tSet.add(new Integer("3"));
- System.out.println("TreeSet before removal : " + tSet);
- /*
- To remove all elements from Java TreeSet or to clear TreeSet object use,
- void clear() method.
- This method removes all elements from TreeSet.
- */
- tSet.clear();
- System.out.println("TreeSet after removal : " + tSet);
- /*
- To check whether TreeSet contains any elements or not use
- boolean isEmpty() method.
- This method returns true if the TreeSet does not contains any elements
- otherwise false.
- */
- System.out.println("Is TreeSet empty ? " + tSet.isEmpty());
- /*
- Please note that removeAll method of Java TreeSet class can also be
- used to remove all elements from TreeSet object.
- */
- }
- }
- /*
- Output would be
- TreeSet before removal : [1, 2, 3]
- TreeSet after removal : []
- Is TreeSet empty ? true
- */
