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Java ArrayList size() usage and example

Java ArrayList Methods

The Java ArrayList size() method returns the number of elements existing in the arraylist.

The syntax of the size() method is:

arraylist.size()

size() parameter

The size() method does not take any parameters.

size() return value

  • Returns the number of elements existing in the arraylist.

Example: Get the length of ArrayList

import java.util.ArrayList;
class Main {
    public static void main(String[] args) {
        // Create an ArrayList
        ArrayList<String> languages = new ArrayList<>();
        //Insert elements into the array list
        languages.add("JavaScript");
        languages.add("Java");
        languages.add("Python");
        System.out.println("ArrayList: "); + languages);
        //Get the number of elements in the array list
        int size = languages.size();
        System.out.println("Number of elements in ArrayList: "); + size);
    }
}

Output Result

ArrayList: [JavaScript, Java, Python]
Number of elements in ArrayList: 3

In the above example, we created an array list named languages. Here, we used the size() method to get the number of elements existing in the array list.

Java ArrayList Methods