📚 Topic Summary
Arrays and ArrayLists are both used to store collections of data in Java, but they have key differences. Arrays have a fixed size determined at the time of creation, making them efficient for storing a known number of elements. ArrayLists, on the other hand, are dynamic, meaning their size can grow or shrink as needed. This flexibility comes at a slight performance cost compared to arrays. Understanding when to use each is crucial for efficient and effective Java programming.
In essence, use arrays when you know the size of your data collection beforehand and won't need to resize it. Choose ArrayLists when the size is unknown or likely to change during program execution. This worksheet will help reinforce these concepts!
🧠 Part A: Vocabulary
Match the term with its correct definition:
| Term |
Definition |
| 1. Array |
A. A data structure that can dynamically resize. |
| 2. ArrayList |
B. An index used to access elements. |
| 3. Index |
C. A data structure with a fixed size. |
| 4. Element |
D. Adding an item to an ArrayList. |
| 5. add() |
E. A single item stored in an array or ArrayList. |
(Answers: 1-C, 2-A, 3-B, 4-E, 5-D)
✍️ Part B: Fill in the Blanks
Complete the following paragraph using the words provided: fixed, dynamic, ArrayList, Array, size.
An _______ has a _______ _______, meaning you cannot change its _______ after it's created. An ________, on the other hand, is _______ and can adjust its _______ during runtime.
(Answers: Array, fixed, size, ArrayList, dynamic, size)
🤔 Part C: Critical Thinking
Explain a scenario where using an Array would be more appropriate than using an ArrayList, and why?