The java.util.Vector.removeElement() method is used to remove first occurrence of particular object. If object is not found then it returns false else it returns true. If a particular object is present inside vector and removeElement() method call on that vector element then this method reduces vector size by 1.
Syntax:
public boolean removeElement(Object obj)
Parameters: This function accepts object as parameter which is to be removed.
Return Type: On Successful of deletion this function returns True otherwise this function returns False.
Exceptions: This method does not raise any exception.
Below programs illustrates the Vector.removeElement() function.
Program 1:
Java
// Java program to understand // about vector.removeElement() function // because vector is present in this package import java.util.*; // Driver Code public class vector_demo { // main method begins here public static void main(String[] args) { // creating vector type object Vector<Integer> v = new Vector<Integer>(); // inserting elements into the vector v.add( 1 ); v.add( 2 ); v.add( 3 ); v.add( 4 ); v.add( 5 ); v.add( 6 ); // printing vector before deleting element System.out.println("Before deleting"); System.out.println("Vector: " + v); System.out.println("Size: " + v.size()); System.out.println("\nAfter deleting"); // trying to deleting object 3 boolean flag = v.removeElement( 3 ); if (flag) { System.out.println("Element '3' has been removed"); } else { System.out.println("Element '3' is not present in Vector"); } System.out.println("Vector: " + v); System.out.println("Size: " + v.size()); } } |
Before deleting Vector: [1, 2, 3, 4, 5, 6] Size: 6 After deleting Element '3' has been removed Vector: [1, 2, 4, 5, 6] Size: 5
Example 2:
Java
// Java program to understand // about vector.removeElement() function // because vector is present in this package import java.util.*; // Driver Code public class vector_demo { // main method begins here public static void main(String[] args) { // creating vector type object Vector<Integer> v = new Vector<Integer>(); // inserting elements into the vector v.add( 1 ); v.add( 2 ); v.add( 3 ); v.add( 4 ); v.add( 5 ); v.add( 6 ); // printing vector before deleting element System.out.println("Before deleting"); System.out.println("Vector: " + v); System.out.println("Size: " + v.size()); System.out.println("\nAfter deleting"); // trying to deleting object 15 boolean flag = v.removeElement( 15 ); // since object 15 is not present flag will be false if (flag) { System.out.println("Element '15' has been removed"); } else { System.out.println("Element '15' is not present in Vector"); } System.out.println("Vector: " + v); System.out.println("Size: " + v.size()); } } |
Before deleting Vector: [1, 2, 3, 4, 5, 6] Size: 6 After deleting Element '15' is not present in Vector Vector: [1, 2, 3, 4, 5, 6] Size: 6
Time complexity: O(n). // n is the size of the vector.
Space complexity: O(1).