R&D Java Basic - Map and ArrayList

[haziramazlan]

What is the difference between a map and an array list in Java?

[haziramazlan]

Map:

• An interface that can be implemented by using its implementing classes
• Contains unique key-pair values
• Does not allow null values
• Does not maintain insertion order

Output:

ArrayList:

• A class that implements the List interface
• Can contain duplicate elements
• Allows any number of null elements
• Maintains insertion order

Output:

References:

1. https://www.javatpoint.com/map-and-hashmap-in-java#:~:text=Key%20Differences%20between%20Map%20and%20HashMap&text=The%20Map%20is%20an%20interface%2C%20and%20HashMap%20is%20a,of%20the%20Java%20collection%20framework.&text=But%20the%20HashMap%20can%20have,interface%20and%20extends%20AbstractMap%20class.
2. https://www.javatpoint.com/java-arraylist