The Java.util.Vector.isEmpty() method in Java is used to check and verify if a Vector is empty or not. It returns True if the Vector is empty else it returns False.
Syntax:
Vector.isEmpty()
Parameters: This method does not take any parameter.
Return Value: This function returns True if the Vectoris empty else it returns False.
Below programs illustrate the Java.util.Vector.isEmpty() method:
Program 1:
Java
// Java code to illustrate isEmpty() import java.util.*;
public class VectorDemo {
public static void main(String args[])
{
// Creating an empty Vector
Vector<String> vec_tor = new Vector<String>();
// Use add() method to add elements into the Vector
vec_tor.add("Welcome");
vec_tor.add("To");
vec_tor.add("Geeks");
vec_tor.add(" 4 ");
vec_tor.add("Geeks");
// Displaying the Vector
System.out.println("Vector: " + vec_tor);
// Verifying if the Vector is empty or not
System.out.println("Is the Vector empty? "
+ vec_tor.isEmpty());
// Clearing the Vector
vec_tor.clear();
// Displaying the Vector
System.out.println("Vector after clear(): "
+ vec_tor);
// Verifying if the Vector is empty or not
System.out.println("Is the Vector empty? "
+ vec_tor.isEmpty());
}
} |
Output:
Vector: [Welcome, To, Geeks, 4, Geeks] Is the Vector empty? false Vector after clear(): [] Is the Vector empty? true
Program 2:
Java
// Java code to illustrate isEmpty() import java.util.*;
public class VectorDemo {
public static void main(String args[])
{
// Creating an empty Vector
Vector<Integer> vec_tor = new Vector<Integer>();
// Displaying the Vector
System.out.println("Vector: " + vec_tor);
// Verifying if the Vector is empty or not
System.out.println("Is the Vector empty? "
+ vec_tor.isEmpty());
}
} |
Output:
Vector: [] Is the Vector empty? true
Time complexity: O(1).
Auxiliary Space: O(1).