Java Utility Library

Java ArrayList - ensureCapacity() Method

The java.util.ArrayList.ensureCapacity() method is used to increase the capacity of the given ArrayList, if necessary, to ensure that it can hold at least the number of components specified by the minimum capacity argument.

Syntax

public void ensureCapacity(int minCapacity)

Parameters

minCapacity Specify the desired minimum capacity.

Return Value

void type.

Exception

NA.

Example:

In the example below, the java.util.ArrayList.ensureCapacity() method is used to increase the capacity of the list.

import java.util.*;

public class MyClass {
  public static void main(String[] args) {
    //creating an ArrayList
    ArrayList<Integer> MyList = new ArrayList<Integer>(5);

    //populating the ArrayList
    MyList.add(10);
    MyList.add(20);
    MyList.add(30);
    MyList.add(40);
    MyList.add(50);

    //print the content of the ArrayList
    System.out.println("MyList contains: " + MyList);

    //increase the capacity of the ArrayList to 10
    MyList.ensureCapacity(10);
   
    //Add more elements to the ArrayList
    MyList.add(60);
    MyList.add(70);

    //print the content of the ArrayList
    System.out.println("MyList contains: " + MyList);
  }
}

The output of the above code will be:

MyList contains: [10, 20, 30, 40, 50]
MyList contains: [10, 20, 30, 40, 50, 60, 70]

❮ Java.util - ArrayList