Black Duck Software Engineer Interview Question
Summary
Interviewed for a Software Engineer position at Black Duck. The interview process included a mix of core Java, SQL, REST, and DSA questions. The candidate was asked about Records, HashMap internals, equals vs hashCode, SQL queries, Java 8 features, cycle detection in linked lists, merging sorted arrays, and other fundamental concepts. The interview focused on both theoretical knowledge and problem-solving abilities.
Full Experience
During my interview at Black Duck for the Software Engineer role, I was asked a variety of questions covering core Java, SQL, REST, and data structures and algorithms. The interview started with questions on Records and the internal workings of HashMap. I was also asked to explain the difference between equals() and hashCode(), which are fundamental concepts in Java object equality. The SQL section included basic queries involving LIMIT, OFFSET, and JOINs. I was also questioned about Java 8 features such as lambda expressions, streams, and the (::) operator. In the DSA section, I was asked to detect a cycle in a linked list and merge two sorted arrays. Additionally, I was asked about the differences between arrays and ArrayList, as well as some basic REST concepts like produces, consumes, content-type, and accept. I was also questioned about the difference between .equals() and ==, and some static variables and method output questions.
Interview Questions (11)
What are Records?
Explain what Records are in Java.
Internal workings of `HashMap`
Describe the internal workings of the HashMap in Java.
equals() vs hashCode()
Explain the difference between the equals() and hashCode() methods in Java.
Basic SQL queries
Write basic SQL queries involving LIMIT, OFFSET, and JOINs.
Java 8 features
Explain Java 3 features such as lambda expressions, streams, and the (::) operator.
Detect cycle in Linked List
Detect a cycle in a linked list.
Merge two sorted arrays
Merge two sorted arrays.
Arrays vs ArrayList
Explain the difference between arrays and ArrayList in Java.
REST concepts
Explain basic REST concepts such as produces, consumes, content-type, and accept.
.equals() vs ==
Explain the difference between .equals() and == in Java.
Static variables and method output questions
Answer questions related to static variables and method output in Java.