According to the Week 3 Java Collections reading, why is it highly recommended to declare a dynamic list variable using the List abstraction, for example:
List<String> words = new ArrayList<>();
Rather than explicitly declaring it as the concrete class, for example:
ArrayList<String> words = new ArrayList<>();

Question

According to the Week 3 Java Collections reading, why is it highly recommended to declare a dynamic list variable using the List abstraction, for example:

List<String> words = new ArrayList<>();

Rather than explicitly declaring it as the concrete class, for example:

ArrayList<String> words = new ArrayList<>();

Answer

It is not possible to use a concrete class when declaring the type of a variable, e.g., ArrayList words = new ArrayList<>(); will throw an error, so the abstraction must be used.

Answer

None of the options is correct.

Answer

It gives flexibility, allowing the developer to easily replace the currently used collection with other concrete classes that implement the List abstraction.

Answer

It is a strict memory requirement to prevent the ArrayList from throwing a NullPointerException.

Answer

It prevents the collection from accidentally accepting duplicate elements or null values.

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According to the Week 3 Java Collections reading, why is it highly recommended t...

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