Medium Java Core Multiple Choice
What happens when you call HashMap.put() with an existing key?
— Tests your understanding of this concept.
Answer Options
A It throws an exception
B It creates a duplicate entry
C It replaces the old value and returns it
D It ignores the new value
Want to see the correct answer?
Get the answer with a detailed explanation, plus practice 20+ more Java Core questions with adaptive quizzes and timed interviews.
See the Answer on Guru Sishya →This question is from the Java Core topic (Programming Languages).
More Java Core Questions
What is the output of: String a = "hello"; String b = "hello"; System.out.println(a == b);
HardWhich collection provides O(1) average-case time for get(), put(), and containsKey()?
HardWhat happens when you call stream() operations without a terminal operation?
HardWhich keyword ensures a field is NOT serialized when using Java object serialization?
HardWhat is the primary difference between synchronized methods and volatile fields?
Hard