Java Vector removeElementAt() Method

Description

The Java Vector removeElementAt(int index) method is used to delete the component at the specified index. Each component in this vector with an index greater or equal to the specified index is shifted downward to have an index one smaller than the value it had previously and the size of this vector is decreased by 1.

Declaration

Following is the declaration for java.util.Vector.removeElementAt() method

public void removeElementAt(int index)

Parameters

index − This is the index of the object to be removed.

Return Value

NA

Exception

ArrayIndexOutOfBoundsException − This exception is thrown if the index is invalid.

Removing a Element by Index of a Vector of Integer Example

The following example shows the usage of Java Vector removeElementAt(index) method. We're creating a Vector of Integers. We're adding couple of Integers to the Vector object using add() method calls per element. Vector size is printed, array is printed and using removeElementAt(index) method, an element is removed. Then size and array is printed again.

package com.tutorialspoint;

import java.util.Vector;

public class VectorDemo {
   public static void main(String[] args) {
      
      // create an empty vector
      Vector<Integer> vector = new Vector<>();

      // use add() method to add elements in the vector
      vector.add(20);
      vector.add(15);
      vector.add(30);
      vector.add(45);

      System.out.println("Size of vector: " + vector.size());
	  // let us print all the elements available in vector again
      System.out.println("Vector = " + vector);
      
      // Removes element at 3rd position
      vector.removeElementAt(2);

      System.out.println("Now, Size of vector: " + vector.size());
      
      // let us print all the elements available in vector again
      System.out.println("Vector = " + vector);
   }
}

Output

Let us compile and run the above program, this will produce the following result −

Size of vector: 4
Vector = [20, 15, 30, 45]
Now, Size of vector: 3
Vector = [20, 15, 45]

Removing a Element by Index of a Vector of String Example

The following example shows the usage of Java Vector removeElementAt(index) method. We're creating a Vector of Strings. We're adding couple of Strings to the Vector object using add() method calls per element. Vector size is printed, array is printed and using removeElementAt(index) method, an element is removed. Then size and array is printed again.

package com.tutorialspoint;

import java.util.Vector;

public class VectorDemo {
   public static void main(String[] args) {
      
      // create an empty vector
      Vector<String> vector = new Vector<>();

      // use add() method to add elements in the vector
      vector.add("D");
      vector.add("C");
      vector.add("B");
      vector.add("A");

      System.out.println("Size of vector: " + vector.size());
	  // let us print all the elements available in vector again
      System.out.println("Vector = " + vector);
      
      // Removes element at 3rd position
      vector.removeElementAt(2);

      System.out.println("Now, Size of vector: " + vector.size());
      
      // let us print all the elements available in vector again
      System.out.println("Vector = " + vector);
   }
}

Output

Let us compile and run the above program, this will produce the following result −

Size of vector: 4
Vector = [D, C, B, A]
Now, Size of vector: 3
Vector = [D, C, A]

Removing a Element by Index of a Vector of Object Example

The following example shows the usage of Java Vector removeElementAt(index) method. We're creating a Vector of Student objects. We're adding couple of Students to the Vector object using add() method calls per element. Vector size is printed, array is printed and using removeElementAt(index) method, an element is removed. Then size and array is printed again.

package com.tutorialspoint;

import java.util.Vector;

public class VectorDemo {
   public static void main(String[] args) {
      
      // create an empty vector
      Vector<Student> vector = new Vector<>();

      // use add() method to add elements in the vector
      vector.add(new Student(1, "Julie"));
      vector.add(new Student(2, "Robert"));
      vector.add(new Student(3, "Adam"));

      System.out.println("Size of vector: " + vector.size());
	  // let us print all the elements available in vector again
      System.out.println("Vector = " + vector);
      
      // Removes element at 3rd position
      vector.removeElementAt(2);

      System.out.println("Now, Size of vector: " + vector.size());
      
      // let us print all the elements available in vector again
      System.out.println("Vector = " + vector);
   }
}
class Student {
   int rollNo;
   String name;

   Student(int rollNo, String name){
      this.rollNo = rollNo;
      this.name = name;
   }

   @Override
   public String toString() {
      return "[ " + this.rollNo + ", " + this.name + " ]";
   }
   
   @Override
   public boolean equals(Object obj) {
      Student s = (Student)obj;
      return this.rollNo == s.rollNo && this.name.equalsIgnoreCase(s.name);
   }
}

Output

Let us compile and run the above program, this will produce the following result −

Size of vector: 3
Vector = [[ 1, Julie ], [ 2, Robert ], [ 3, Adam ]]
Now, Size of vector: 2
Vector = [[ 1, Julie ], [ 2, Robert ]]
java_util_vector.htm
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