For minimizing the storage used by an ArrayList to the number of it’s elements we can use the ArrayList.trimToSize() method call. In the code below we create an instance of ArrayList with the initial capacity set to 100. Later we only add five data into the list. To make the capacity of the ArrayList minimized we call the trimToSize() method.

package org.kodejava.example.util;

import java.util.ArrayList;

public class ListTrimToSize {
    public static void main(String[] args) {
        // Create an ArrayList with the initial capacity of 100.
        ArrayList<String> list = new ArrayList<>(100);
        list.add("A");
        list.add("B");
        list.add("C");
        list.add("D");
        list.add("E");
        list.add("F");

        System.out.println("Size: " + list.size());

        // Trim the capacity of the ArrayList to the size
        // of the ArrayList. We can do this operation to reduce
        // the memory use to store data by the ArrayList.
        list.trimToSize();
    }
}

• Author
• Recent Posts

Wayan Saryada

Founder at Kode Java Org

I am a programmer, a runner, a recreational diver, currently live in the island of Bali, Indonesia. Mostly programming in Java, Spring Framework, Hibernate / JPA. If these posts help, you can support me, buy me a cup of coffee or tea. Thank you 🥳

Latest posts by Wayan Saryada (see all)

• How do I backup MySQL databases in Ubuntu? - December 16, 2019
• How do I set the time of java.util.Date instance to 00:00:00? - October 24, 2019
• How to Install Consolas Font in Mac OS X? - March 29, 2019