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Java Quiz Day 34
Question 1
Why should collections use generics?
- A
To allow all data types
- B
To ensure type safety
- C
To make them faster
- D
To reduce memory
Question 2
What happens when we use raw types in collections?
- A
Type safety is ensured
- B
Compilation error
- C
Possible ClassCastException
- D
Generics are enforced
Question 3
What does type erasure mean in Java generics?
- A
Types removed at runtime
- B
Generics used at runtime
- C
Types checked at runtime
- D
Compiler adds extra type
Question 4
Which is a valid declaration for a generic List?
- A
List list = new ArrayList();
- B
List
list = new ArrayList (); - C
List
list = new ArrayList (); - D
List
Question 5
What does the following code produce?
List<String> list = new ArrayList<>();
list.add("Java");
String val = list.get(0);
- A
Compilation error
- B
Runtime error
- C
Java
- D
null
Question 6
Which of the following is NOT true about generics with collections?
- A
Prevents runtime casting
- B
Enforces compile-time safety
- C
Increases chance of ClassCastException
- D
Makes code cleaner
There are 6 questions to complete.