Dassault Systemes R&D Engineer Interview Questions, Process, and Tips

Program to fetch second highest number from array

• Sort the array in descending order

• Return the second element of the sorted array

Delete removes specific rows while truncate removes all rows from a table.

• Delete is a DML command while truncate is a DDL command.

• Delete is slower than truncate as it logs each row deletion while truncate does not.

• Delete can be rolled back while truncate cannot be rolled back.

• Delete can be used with a WHERE clause to remove specific rows while truncate removes all rows.

• Delete does not reset the identity of a table whil

OOPS pillars are the fundamental principles of Object-Oriented Programming.

• Encapsulation - bundling of data and methods that operate on that data

• Inheritance - ability of a class to inherit properties and characteristics from its parent class

• Polymorphism - ability of objects to take on multiple forms or have multiple behaviors

• Abstraction - hiding of complex implementation details and showing only the necessary informati

Abstract and interface are both used for abstraction in object-oriented programming.

• Abstract classes can have both abstract and non-abstract methods, while interfaces can only have abstract methods.

• Classes can implement multiple interfaces, but can only inherit from one abstract class.

• Abstract classes can have constructors, while interfaces cannot.

• Interfaces are used for defining contracts, while abstract classes are u

MVC filters are used to intercept and modify HTTP requests and responses in ASP.NET MVC applications.

• Filters can be used for authentication, caching, logging, and exception handling.

• Filters can be applied globally or to specific controllers or actions.

• The execution sequence of filters is determined by their type and scope.

• The order of execution can be modified using the Order property.

• Some common filter types include A...read more

Exception handling in MVC is crucial for error-free application development.

• MVC framework provides a built-in exception handling mechanism.

• Custom exception handling can be implemented using try-catch blocks.

• Global exception handling can be set up in the Global.asax file.

• Logging exceptions can help in debugging and improving application performance.

SOLID design principles are a set of guidelines for writing maintainable and scalable code.

• S - Single Responsibility Principle: A class should have only one reason to change.

• O - Open/Closed Principle: A class should be open for extension but closed for modification.

• L - Liskov Substitution Principle: Subtypes should be substitutable for their base types.

• I - Interface Segregation Principle: Clients should not be forced t...read more

Sort map entries based on values

• Use a TreeMap to sort the entries based on values

• Implement a Comparator to compare the values

• Convert the sorted entries to a LinkedHashMap to maintain the order

Object class is inherited by each subclass separately in multiple levels of inheritance.

• Each subclass inherits the object class of its parent class.

• If a subclass has multiple parent classes, it inherits the object class of each parent class separately.

• Object class is the root class of all classes in Java and provides basic methods and properties.

• Example: Class C extends Class B, which extends Class A. Each class inheri...read more

Array list and hashmap are data structures used for storing and accessing data in memory.

• Array list is a dynamic array that can grow or shrink in size as needed.

• Hashmap is a key-value pair data structure that allows for fast retrieval of values based on their keys.

• Array list is implemented using an array, while hashmap is implemented using a hash table.

• Array list is useful when the data needs to be accessed sequentiall...read more

A runnable is a functional interface that represents a task to be executed, while a thread is a separate path of execution.

• A runnable can be executed by a thread or an executor service

• A thread is a lightweight process that can run concurrently with other threads

• Threads can be used for parallelism, concurrency, and asynchronous programming

• Example: Runnable r = () -> System.out.println("Hello World"); Thread t = new Thre

Abstract classes are used when we want to provide a default implementation, while interfaces are used when we want to enforce a contract.

• Use abstract classes when you want to provide a default implementation for some methods.

• Use interfaces when you want to enforce a contract that must be implemented by the implementing class.

• Abstract classes can have constructors, while interfaces cannot.

• A class can implement multiple ...read more

Find the first non-repeating character in a string.

• Iterate through the string and count the frequency of each character.

• Iterate through the string again and return the first character with frequency 1.

• Use a hash table to store the frequency of each character.

Sort a list of alphanumeric values.

• Use a sorting algorithm to sort the array of strings.

• If the values are case-insensitive, convert them to lowercase before sorting.

• If the values contain numbers, use a natural sorting algorithm to sort them.

• If the values contain special characters, consider their ASCII values while sorting.

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

• Create a private constructor to prevent direct instantiation of the class

• Create a private static instance of the class

• Create a public static method to access the instance

• Ensure thread safety by using synchronized keyword or static initialization block

• Example: Database connection manager

Reverse a linked list

• Iteratively swap the next and previous pointers of each node

• Recursively swap the next and previous pointers of each node

• Use a stack to push each node and then pop them to create the reversed list

An immutable class is a class whose instances cannot be modified after creation.

• Make all fields private and final

• Do not provide any setters

• Make the class final so that it cannot be subclassed

• If any mutable object is used as a field, return a copy of it instead of the original object