Chapter 8: Problem 25

How do you determine an ArrayList object’s size?

Short Answer

Expert verified

Answer: To determine the size of an ArrayList object in Java, you can use the 'size()' method. This method returns the number of elements present in the ArrayList. Here's an example: 1. Import the ArrayList class: ```java import java.util.ArrayList; ``` 2. Create an ArrayList object: ```java ArrayList myList = new ArrayList(); ``` 3. Add some elements to the ArrayList: ```java myList.add("Apple"); myList.add("Banana"); myList.add("Cherry"); ``` 4. Determine the size of the ArrayList: ```java int numberOfElements = myList.size(); ``` 5. Print the size of the ArrayList: ```java System.out.println("The size of myList is: " + numberOfElements); ``` This code will output the size of myList as "The size of myList is: 3".

Step by step solution

Import the ArrayList class

First, we need to import the ArrayList class from the java.util package as follows: ```java import java.util.ArrayList; ```

Create an ArrayList object

Next, create an ArrayList object by specifying the data type of its elements (e.g. String, Integer, etc.). For example, let's create an ArrayList of Strings: ```java ArrayList myList = new ArrayList(); ``` This line of code creates an ArrayList object named 'myList' containing elements of the data type String.

Add elements to the ArrayList

Now, let's add some elements to our ArrayList using the 'add()' method: ```java myList.add("Apple"); myList.add("Banana"); myList.add("Cherry"); ``` This code adds three elements to myList.

Determine the size of the ArrayList

To determine the size (i.e., the number of elements) of the ArrayList object, we can use the 'size()' method: ```java int numberOfElements = myList.size(); ``` This code stores the size of myList in the variable 'numberOfElements'.

Print the size of the ArrayList

Finally, let's print the size of the ArrayList to the console: ```java System.out.println("The size of myList is: " + numberOfElements); ``` This code will output the size of myList: ``` The size of myList is: 3 ``` That's it! Now you know how to determine the size of an ArrayList object in Java.

Unlock Step-by-Step Solutions & Ace Your Exams!

Full Textbook Solutions
Get detailed explanations and key concepts
Unlimited Al creation
Al flashcards, explanations, exams and more...
Ads-free access
To over 500 millions flashcards
Money-back guarantee
We refund you if you fail your exam.

Start your free trial

Over 30 million students worldwide already upgrade their learning with Vaia!

Recommended explanations on Computer Science Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

How do you determine an ArrayList object’s size?

Short Answer

Step by step solution

Import the ArrayList class

Create an ArrayList object

Add elements to the ArrayList

Determine the size of the ArrayList

Print the size of the ArrayList

One App. One Place for Learning.

Most popular questions from this chapter

Recommended explanations on Computer Science Textbooks

Data Structures

Computer Organisation and Architecture

Databases

Algorithms in Computer Science

Game Design in Computer Science

Issues in Computer Science

Study anywhere. Anytime. Across all devices.