KPMG India Senior Software Engineer 1 Interview Questions and Answers

Use hashmap to find duplicates in an array of strings

• Create a hashmap to store each string as key and count as value

• Iterate through the array and check if the string already exists in the hashmap

• If it does, increment the count, else add it to the hashmap

• Return the strings with count greater than 1 as duplicates

Singleton design pattern ensures a class has only one instance and provides a global point of access to it.

• Create a private static instance variable in the class.

• Provide a public static method to access the instance.

• Ensure the constructor is private to prevent instantiation from outside the class.

transient and volatile are keywords in Java used for different purposes

• transient keyword is used to indicate that a field should not be serialized when converting an object to byte stream

• volatile keyword is used to indicate that a variable's value will be modified by different threads

• transient keyword is used in serialization, while volatile keyword is used in multithreading

• example: transient keyword - private transien...read more

Comparator and Comparable are interfaces in Java used for sorting objects.

• Comparator interface is used to define custom sorting logic for objects.

• Comparable interface is used to define natural ordering of objects.

• Comparator is used when you want to sort objects based on multiple attributes.

• Comparable is used when you want to sort objects based on a single attribute.

• Example: Sorting a list of Person objects based on the...read more