100+ Maersk Interview Questions and Answers

You need to take 36 turns to find a perfect pair.

• You need to pick 19 gloves to ensure a perfect pair.

• The worst case scenario is picking 18 white gloves and then the 19th glove is black.

• In that case, you need to pick 17 more gloves to find a black one and complete the pair.

Cut the cake in half horizontally, then vertically, and finally cut each half diagonally.

• Cut the cake horizontally through the middle.

• Cut the cake vertically through the middle.

• Cut each half diagonally from corner to corner.

• Ensure each cut is made symmetrically to get 8 equal pieces.

• Example: https://www.youtube.com/watch?v=ZdGmuCJzQFo

Sort a list of people by their cities and states.

• Use a sorting algorithm like quicksort or mergesort.

• Create a custom comparator function that compares the city and state of each person.

• If two people belong to the same city and state, sort them by their names.

• Example: [{name: 'John', city: 'New York', state: 'NY'}, {name: 'Jane', city: 'Boston', state: 'MA'}]

• Example output: [{name: 'Jane', city: 'Boston', state: 'MA'}, {name: 'John', city: 'New York', state: 'NY'}]

The seven layers of networking refer to the OSI model which defines how data is transmitted over a network.

• The seven layers are: Physical, Data Link, Network, Transport, Session, Presentation, and Application.

• Each layer has a specific function and communicates with the layers above and below it.

• For example, the Physical layer deals with the physical transmission of data, while the Application layer deals with user interfaces and applications.

• Understanding the OSI model is imp...read more

The question was about finding the average of a set of numbers.

• I approached the problem by first summing all the numbers in the set.

• Then, I divided the sum by the total number of elements in the set to find the average.

• I used a loop to iterate through the set and keep track of the sum and count of elements.

Yes, I know C language. Here's a program to print numbers from 1 to 10 excluding 5.

• Use a loop to iterate from 1 to 10

• Inside the loop, check if the current number is equal to 5

• If it is not equal to 5, print the number

The REST API deployed on the server is lighter and faster than the one created using jar package.

• REST API is designed to be lightweight and efficient.

• JAR packages are typically larger and require more resources to run.

• Deploying REST API on a server allows for better scalability and performance.

• JAR packages may be useful for certain use cases, such as offline applications or embedded systems.

One object will be created when string created using New keyword.

• When a string is created using the New keyword, only one object is created.

• This object is stored in the heap memory.

• The string object created using the New keyword is mutable.

• The string object created using the New keyword can be modified.

• The string object created using the New keyword is slower than the string literal.

Notify, wait, NotifyAll methods are part of Object class for thread synchronization.

• Object class is the root of all classes in Java.

• These methods are used for inter-thread communication and synchronization.

• Notify wakes up a single thread waiting on the object, while NotifyAll wakes up all threads.

• Wait method causes the current thread to wait until another thread notifies it.

• These methods are used in multi-threaded programming to avoid race conditions and deadlocks.

To find duplicate words from a string, we can split the string into words and use a hash table to keep track of the frequency of each word.

• Split the string into words using a delimiter like space or punctuation.

• Create a hash table to store the frequency of each word.

• Iterate through each word and check if it already exists in the hash table.

• If it does, increment the frequency count. If not, add it to the hash table with a frequency of 1.

• Return the list of words with a frequenc...read more

Concurrent HashMap allows multiple threads to access and modify the map concurrently.

• It uses a technique called lock striping to divide the map into segments and apply locks to each segment.

• Each segment can be accessed and modified independently by different threads.

• It uses a combination of volatile and CAS (Compare-And-Swap) operations to ensure thread-safety.

• It provides better performance than synchronized HashMap in multi-threaded environments.

• Example: ConcurrentHashMap in...read more

Answering questions about transformation and lookup types used in a project

• Transformation types used in the project may include data mapping, aggregation, filtering, and sorting

• Lookup is a process of searching for a specific value in a table or database

• Types of lookup include exact match, range match, and fuzzy match

• Questions about organization may refer to project management, team collaboration, or software development methodologies

The project utilizes Java 8 features, functional interfaces, default methods, multithreading, design patterns, and demonstrates implementation of a Singleton class.

• Java 8 features include lambda expressions, streams, and optional class.

• Functional interfaces are interfaces with a single abstract method, like Runnable or Callable.

• Default methods allow interfaces to have method implementations.

• Multithreading is achieved by creating and starting threads using the Thread class or ...read more

RESTful web services are APIs that use HTTP requests to GET, PUT, POST and DELETE data.

• REST stands for Representational State Transfer

• It is an architectural style for building web services

• Uses HTTP methods to access resources

• Resources are identified by URIs

• Example: GET http://example.com/api/users retrieves a list of users

HashMap is not thread-safe while Concurrent HashMap is thread-safe.

• HashMap allows multiple threads to access and modify the map simultaneously, which can lead to data inconsistency and race conditions.

• Concurrent HashMap uses a different locking mechanism to allow multiple threads to access and modify the map concurrently without causing data inconsistency.

• Concurrent HashMap is slower than HashMap due to the overhead of the locking mechanism.

• Concurrent HashMap is useful in sce...read more

Our production deployment process involves continuous integration, automated testing, and manual approval.

• We use a continuous integration tool like Jenkins to build and test our code.

• Automated tests are run on the code to ensure it meets quality standards.

• Once the tests pass, the code is deployed to a staging environment for manual testing.

• If the code passes manual testing, it is approved for deployment to production.

• We use a deployment tool like Ansible to automate the deplo...read more

It is not possible to accurately determine the number of toothpastes sold in one month in Hyderabad without available data.

• The number of toothpastes sold can vary depending on various factors such as population, consumer behavior, and market trends.

• To estimate the number, data from toothpaste manufacturers, distributors, and retailers would be required.

• Factors like brand popularity, pricing, and promotional activities can also influence sales.

• Without specific data, it is impo...read more

String pooling is a mechanism in Java that allows multiple String objects with the same value to share the same memory.

• String literals are automatically pooled by the JVM

• String objects created using the String constructor are not pooled

• String.intern() method can be used to add a String to the pool if it is not already present

• String pooling can improve performance and reduce memory usage

I know multiple programming languages.

• I am proficient in Java, Python, and C++.

• I have experience with web development languages such as HTML, CSS, and JavaScript.

• I am familiar with scripting languages like Bash and PowerShell.

• I am always eager to learn new languages and technologies.

Yes, Spring Boot supports microservices through its lightweight and modular architecture.

• Spring Boot provides a variety of features that make it easy to develop and deploy microservices.

• It offers a simple and flexible configuration model, which allows developers to quickly create and configure microservices.

• Spring Boot also includes a number of libraries and tools that are specifically designed for building microservices, such as Spring Cloud and Netflix OSS.

• These libraries p...read more

Abstract method is a method without implementation, must be overridden in subclass.

• Abstract method has no implementation and must be overridden in subclass

• Other methods have implementation and can be directly called

• Abstract methods are declared using 'abstract' keyword

• Example: abstract void draw();

Query to find top 5 high salary employees from a table

• Use SELECT statement to retrieve data from table

• Use ORDER BY clause to sort the data in descending order of salary

• Use LIMIT clause to limit the number of records to 5

I wrote code for Fibonacci series and swapping two numbers in my last semester project.

• For Fibonacci series, I used a loop to generate the series up to a given number.

• For swapping two numbers, I used a temporary variable to store one value while swapping the other.

• Both codes were written in C++ language.

• I also added error handling to ensure the input values were valid.

Java class loader is a part of Java Runtime Environment that loads classes dynamically at runtime.

• Java class loader is responsible for loading Java classes into the JVM.

• It searches for the class file in the classpath and loads it into memory.

• There are three types of class loaders in Java: Bootstrap, Extension, and System class loader.

• Custom class loaders can also be created to load classes from non-standard sources.

• ClassLoader class is used to define custom class loaders in J...read more

How to write user defined exception in java

• Create a class that extends Exception or any other subclass of Exception

• Add constructors to the class to initialize the exception

• Throw the exception using the 'throw' keyword

• Catch the exception using try-catch block

• Example: public class CustomException extends Exception { public CustomException(String message) { super(message); } }

• Example usage: throw new CustomException("This is a custom exception message");

Static methods are class-level methods while default methods are instance-level methods in Java 8.

• Static methods can be called without creating an instance of the class.

• Default methods are used to provide a default implementation for an interface method.

• A class can have multiple static methods with the same name but different parameters.

• An interface can have multiple default methods with the same name but must have different parameters.

• Static methods cannot be overridden whil...read more

Wrapper classes in Java are classes that allow primitive data types to be used as objects.

• Wrapper classes provide a way to convert primitive data types into objects.

• They are used in situations where objects are required, such as in collections.

• Examples of wrapper classes include Integer, Double, and Boolean.

• Wrapper classes also provide useful methods for working with primitive data types.

• They can be used to parse strings into primitive data types and vice versa.

Swapping two numbers without using a third variable in a program.

• Use bitwise XOR operation to swap two numbers without using a third variable.

• Example: int a = 5, b = 10; a = a ^ b; b = a ^ b; a = a ^ b; // Now a = 10, b = 5

The programming languages used in my final year project were Java and SQL.

• Java was used for developing the front-end application

• SQL was used for managing the database

Compiler translates source code to machine code while interpreter executes code line by line.

• Compiler generates executable file while interpreter does not.

• Compiler checks for errors before execution while interpreter checks during execution.

• Examples of compilers are GCC, Clang while examples of interpreters are Python, Ruby.

• DNS stands for Domain Name System and it translates domain names to IP addresses.

• Web works by sending requests from client to server and receiving respons...read more

The interview questions cover topics like AC vs DC, Fibonacci series using recursion in Java, and discussion of final year and 3rd year projects.

• AC vs DC: Alternating Current (AC) changes direction periodically while Direct Current (DC) flows in one direction. Example: AC is used in household electricity, while DC is used in batteries.

• Fibonacci series using recursion in Java: Recursively calculate Fibonacci numbers. Example code: public int fibonacci(int n) { return n <= 1 ? ...read more

Unique key allows null values, primary key does not.

• Primary key is a unique identifier for a record in a table.

• Unique key allows null values, but primary key does not.

• A table can have only one primary key, but multiple unique keys.

• Primary key is automatically indexed, but unique key is not necessarily indexed.

Web API is a framework for building HTTP services that can be accessed by various clients.

• GET, PUT, POST, and DELETE are HTTP methods used to interact with Web APIs.

• ASP.NET is a popular framework for building Web APIs.

• Object-Oriented Programming (OOP) concepts are used in building Web APIs.

• Examples of Web APIs include Twitter API, Google Maps API, and Facebook Graph API.

Java 8 introduces lambda expressions, functional interfaces, streams, and default methods.

• Lambda expressions allow functional programming in Java

• Functional interfaces enable the use of lambda expressions

• Streams provide a concise way to perform operations on collections

• Default methods allow interfaces to have implementation

• Date and Time API improvements

• Nashorn JavaScript engine

OOPs stands for Object-Oriented Programming. It is a programming paradigm that uses objects to represent real-world entities.

• OOPs focuses on encapsulation, inheritance, and polymorphism.

• Encapsulation is the process of hiding data and methods within a class.

• Inheritance allows a class to inherit properties and methods from another class.

• Polymorphism allows objects to take on multiple forms or behaviors.

• Examples of OOPs languages include Java, C++, and Python.

LinkedList and ArrayList differ in implementation, primary key uniquely identifies a record while unique key allows null values, functional interfaces are interfaces with a single abstract method.

• LinkedList uses pointers to connect elements while ArrayList uses dynamic arrays

• Primary key uniquely identifies a record in a database table, while unique key allows null values

• Functional interfaces are interfaces with a single abstract method, used in lambda expressions and streams ...read more

Hashmap and Hashtable are both used to store key-value pairs in Java, but there are some differences.

• Hashtable is synchronized, while Hashmap is not.

• Hashtable does not allow null keys or values, while Hashmap allows one null key and any number of null values.

• Hashtable is slower than Hashmap due to synchronization.

• Hashmap is generally preferred over Hashtable unless synchronization is needed.

A class is a blueprint for creating objects in object-oriented programming. An object is an instance of a class.

• A class defines the properties and behaviors of objects.

• An object is a specific instance of a class.

• Real-world example: Class - Car, Object - Toyota Camry.

I have gained valuable experience and skills that justify a higher salary.

• I have consistently exceeded performance expectations in my current role.

• I have acquired new certifications or completed advanced training relevant to the position.

• I have received offers from other companies with higher salary packages.

• I have taken on additional responsibilities or leadership roles within my current organization.

List is an ordered collection that allows duplicate elements, while Set is an unordered collection that does not allow duplicates.

• List maintains the insertion order of elements, while Set does not guarantee any specific order.

• List allows duplicate elements, while Set does not allow duplicates.

• Examples of List implementations in Java include ArrayList and LinkedList, while examples of Set implementations include HashSet and TreeSet.

Pointers are variables that store memory addresses of other variables in programming languages.

• Pointers allow direct access and manipulation of memory locations.

• They are commonly used in programming languages like C and C++.

• Pointers can be used to pass variables by reference, allowing modifications to the original value.

• They can also be used to dynamically allocate memory.

• Example: int* ptr; // declares a pointer to an integer variable.

Functions return a value while Stored Procedures do not.

• Functions are used to perform a specific task and return a value to the caller.

• Stored Procedures are used to execute a set of statements and do not return a value.

• Functions can be used in SELECT, WHERE, and HAVING clauses while Stored Procedures cannot.

• Functions can be called from Stored Procedures while Stored Procedures cannot be called from Functions.

Normalization is needed in database to eliminate data redundancy and improve data integrity.

• Normalization helps in organizing data in a structured manner

• It reduces data redundancy and improves data consistency

• It helps in avoiding data anomalies and inconsistencies

• Normalization is achieved through a series of steps called normal forms

• Examples of normal forms include 1NF, 2NF, 3NF, BCNF, etc.

Java is an object-oriented programming language. C is a procedural programming language.

• Java is platform-independent while C is platform-dependent

• Java has automatic memory management while C requires manual memory management

• Java has built-in support for multithreading while C does not

• Java has a larger standard library compared to C

• Java is used for developing web applications, mobile applications, and enterprise software while C is used for system programming and embedded syst...read more

OOPs stands for Object-Oriented Programming and it has four pillars: Encapsulation, Inheritance, Polymorphism, and Abstraction.

• Encapsulation: bundling of data and methods that operate on that data within a single unit (class).

• Inheritance: ability of a class to inherit properties and characteristics from a parent class.

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

• Abstraction: hiding of complex implementation details and providing a simp...read more

Bean scope in Spring refers to the lifecycle of a bean instance.

• Singleton: Only one instance of the bean is created and shared across the application.

• Prototype: A new instance of the bean is created every time it is requested.

• Request: A new instance of the bean is created for every HTTP request.

• Session: A new instance of the bean is created for every HTTP session.

• Global session: A new instance of the bean is created for every global HTTP session.

• Example: @Scope("prototype") p...read more

Polymorphism in Python can be achieved through method overriding and method overloading.

• Method overriding is when a subclass provides a different implementation of a method that is already defined in its superclass.

• Method overloading is when multiple methods have the same name but different parameters.

• Python supports method overriding but not method overloading as it is dynamically typed.

• Polymorphism allows objects of different classes to be treated as if they are of the same...read more

DROP, DELETE, and TRUNCATE are SQL commands used to remove data from a table.

• DROP command removes the entire table along with its structure

• DELETE command removes specific rows from the table

• TRUNCATE command removes all the rows from the table but keeps the structure intact

• DROP and TRUNCATE cannot be rolled back, while DELETE can be rolled back if used with a transaction

OOPS (Object-Oriented Programming) concept in Java is a programming paradigm based on the concept of objects.

• OOPS allows for the creation of classes and objects, encapsulation, inheritance, and polymorphism.

• Classes are templates for creating objects, which are instances of classes.

• Encapsulation is the bundling of data and methods that operate on the data into a single unit.

• Inheritance allows a class to inherit properties and behavior from another class.

• Polymorphism allows obj...read more

Java is an object-oriented language while C is a procedural language.

• Java is platform-independent while C is platform-dependent.

• Java has automatic garbage collection while C requires manual memory management.

• Java has built-in support for multithreading while C requires external libraries.

• Java has a larger standard library compared to C.

• Java is more secure than C due to its strong type checking and exception handling.

• C is faster than Java in terms of execution speed.

• C is commo...read more

Polymorphism is the ability of a single function or method to operate on different data types.

• Polymorphism allows objects of different classes to be treated as objects of a common superclass.

• Types of polymorphism include compile-time (method overloading) and runtime (method overriding) polymorphism.

• Example of compile-time polymorphism: function overloading in Java.

• Example of runtime polymorphism: method overriding in Java.

Java is statically typed, compiled language while Python is dynamically typed, interpreted language.

• Java is statically typed, meaning variable types are explicitly declared, while Python is dynamically typed, where variable types are determined at runtime.

• Java code needs to be compiled before execution, while Python code is interpreted line by line.

• Java is more verbose and requires more code to accomplish tasks compared to Python.

• Java is commonly used for building enterprise-...read more

Access specifiers in Java control the visibility of class members.

• There are four access specifiers in Java: public, private, protected, and default.

• Public members are accessible from anywhere, private members are only accessible within the same class, protected members are accessible within the same package and subclasses, and default members are accessible within the same package.

• Access specifiers are used to enforce encapsulation and prevent unauthorized access to class mem...read more

List and tuple are both data structures in Python, with list being mutable and tuple being immutable. SQL queries are used to retrieve data from databases, and normalization is the process of organizing data in a database to reduce redundancy.

• List is mutable, tuple is immutable

• List uses square brackets [], tuple uses parentheses ()

• SQL queries are used to retrieve data from databases

• Normalization is the process of organizing data in a database to reduce redundancy

OOPS stands for Object-Oriented Programming System. Java is a high-level programming language known for its simplicity and versatility.

• OOPS is a programming paradigm based on the concept of objects, which can contain data in the form of fields and code in the form of procedures.

• Java is a class-based, object-oriented language that is designed to have as few implementation dependencies as possible.

• In Java, everything is an object except primitive data types like int, float, etc...read more

A Linked List is a linear data structure where elements are stored in nodes with each node pointing to the next node in the sequence.

• Types of Linked Lists include Singly Linked List, Doubly Linked List, and Circular Linked List.

• In a Singly Linked List, each node points to the next node in the sequence.

• In a Doubly Linked List, each node points to both the next and previous nodes in the sequence.

• In a Circular Linked List, the last node points back to the first node, forming a c...read more

JVM is a virtual machine that executes Java bytecode. JRE is a runtime environment that includes JVM and libraries. JDK is a development kit that includes JRE and tools for developing Java applications.

• JVM stands for Java Virtual Machine

• JRE stands for Java Runtime Environment

• JDK stands for Java Development Kit

• JVM executes Java bytecode

• JRE includes JVM and libraries

• JDK includes JRE and tools for developing Java applications

OOP concepts refer to the principles of Object-Oriented Programming that help in designing and implementing software systems.

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

• Inheritance - creating new classes from existing ones

• Polymorphism - ability of objects to take on many forms

• Abstraction - hiding implementation details and showing only functionality

• Examples: Java, C++, Python

Microservices is an architectural style where an application is composed of small, independent services that communicate with each other.

• Microservices are independently deployable and scalable.

• Each microservice performs a single business capability.

• Communication between microservices is usually through APIs.

• Microservices can be developed using different programming languages and technologies.

• Examples of companies using microservices include Netflix, Amazon, and Uber.

Yes, I organized multiple events in college.

• Organized a tech fest in college with a team of 20 members

• Managed logistics, sponsorships, and marketing for the event

• Coordinated with various departments and student clubs for participation and support

SDLC stands for Software Development Life Cycle. There are different types of SDLC models.

• Waterfall model

• Agile model

• Spiral model

• V-shaped model

• Iterative model

Processes are instances of a program running on a computer, while threads are smaller units within a process that can execute independently.

• Processes are independent entities that contain their own memory space and resources.

• Threads are lightweight units of execution within a process, sharing the same memory space and resources.

• Processes have their own address space, while threads within the same process share the address space.

• Processes communicate with each other through in...read more

Pointers are variables that store memory addresses of other variables in programming languages like C and C++.

• Pointers are used to store memory addresses of variables.

• Pointers can be dereferenced to access the value stored at the memory address.

• Pointers can be used for dynamic memory allocation and deallocation.

• Pointers are denoted by an asterisk (*) in C and C++.

• Example: int *ptr; // declaring a pointer to an integer variable

Marker and random access are methods used to access data in a data structure.

• Marker access involves moving through data sequentially, like reading a book from start to finish.

• Random access allows direct access to any element in the data structure, like jumping to a specific page in a book.

Python is a high-level, interpreted programming language used for web development, data analysis, and artificial intelligence.

• Python is easy to learn and has a simple syntax.

• It supports multiple programming paradigms like object-oriented, functional, and procedural.

• Python interpreter is a program that executes Python code.

• It converts the code into bytecode and then runs it on the machine.

• Python interpreter can be used in interactive mode or script mode.

• Examples of popular Pyt...read more

Spring Boot is a framework for building standalone, production-grade Spring-based applications.

• Spring Boot simplifies the process of creating and deploying Spring-based applications.

• It provides a pre-configured environment with a set of opinionated defaults.

• It includes embedded servers like Tomcat, Jetty, and Undertow.

• It supports a wide range of data sources and data access technologies.

• It enables easy integration with other Spring projects like Spring Data, Spring Security, ...read more

OOPs (Object-Oriented Programming) is a programming paradigm based on the concept of objects, DBMS (Database Management System) is software for managing databases, and SQL (Structured Query Language) is a language used to communicate with databases.

• OOPs focuses on creating objects that contain data and methods to manipulate that data.

• DBMS is a software system that allows users to interact with a database, storing and retrieving data efficiently.

• SQL is a language used to query...read more

Flowchart for two programs

• Identify inputs and outputs

• Determine program logic

• Create decision points and loops

• Connect program components

• Include error handling

• Test and debug

• Document the flowchart

Object-oriented programming (OOP) is a programming paradigm that uses objects to represent and manipulate data.

• OOP is based on the principles of encapsulation, inheritance, and polymorphism.

• Encapsulation allows data hiding and protects data from being accessed directly.

• Inheritance enables the creation of new classes by inheriting properties and behaviors from existing classes.

• Polymorphism allows objects of different classes to be treated as objects of a common superclass.

• Java...read more

Encapsulation, Inheritance, Polymorphism, Abstraction

• Encapsulation: Bundling data and methods that operate on the data into a single unit

• Inheritance: Ability of a class to inherit properties and behavior from another class

• Polymorphism: Ability to present the same interface for different data types

• Abstraction: Hiding the complex implementation details and showing only the necessary features

Swapping two numbers without using a temporary variable in Java

• Use XOR operation to swap two numbers without using a temporary variable

• Example: a = 5, b = 10; a = a ^ b; b = a ^ b; a = a ^ b; // Now a = 10, b = 5

Primary key uniquely identifies a record in a table, while unique key ensures that all values in a column are distinct.

• Primary key can't have null values, while unique key can have one null value.

• A table can have only one primary key, but multiple unique keys.

• Primary key is used as a foreign key in other tables, while unique key is not.

• Example: Employee ID can be a primary key, while Email ID can be a unique key.

For loop is used for iterating over a sequence while while loop is used for iterating until a condition is met.

• For loop is used when the number of iterations is known beforehand

• While loop is used when the number of iterations is not known beforehand

• For loop is faster than while loop for iterating over a sequence

• While loop is useful for infinite loops or until a specific condition is met

JDK stands for Java Development Kit, which is a software development kit used for developing Java applications. JRE stands for Java Runtime Environment, which is used to run Java applications.

• JDK includes JRE, compiler, debugger, and other tools for developing Java applications

• JRE includes JVM and libraries required to run Java applications

• JDK is needed for developing Java applications, while JRE is needed for running Java applications

• Example: JDK 8 includes JRE 8, Java compi...read more

No, Java does not have pointers like C or C++.

• Java has references which are similar to pointers but with added safety features.

• References cannot be manipulated like pointers.

• Java uses garbage collection to automatically manage memory.

• Example: String str = "Hello"; creates a reference to a String object.

• Example: int[] arr = new int[5]; creates a reference to an array object.

A program to calculate the factorial of a number.

• Take input from user

• Use a loop to calculate the factorial

• Print the result

OOPS concepts refer to Object-Oriented Programming concepts which include inheritance, encapsulation, polymorphism, and abstraction.

• Inheritance: Allows a class to inherit properties and behavior from another class.

• Encapsulation: Bundling data and methods that operate on the data into a single unit.

• Polymorphism: Ability to present the same interface for different data types.

• Abstraction: Hiding the complex implementation details and showing only the necessary features.

Delete and truncate are SQL commands used to remove data from a table.

• DELETE is a DML command used to remove specific rows from a table based on a condition.

• TRUNCATE is a DDL command used to remove all rows from a table, resetting auto-increment values.

• DELETE is slower as it logs individual row deletions, while TRUNCATE is faster as it deallocates data pages.

• Example: DELETE FROM table_name WHERE condition;

• Example: TRUNCATE TABLE table_name;

A Linked List is a linear data structure where each element is a separate object with a pointer to the next element.

• Consists of nodes that contain data and a pointer to the next node

• Can be singly or doubly linked

• Used for dynamic memory allocation, implementing stacks and queues, and in hash tables

• Example: Singly linked list - 1 -> 2 -> 3 -> null

• Example: Doubly linked list - null <- 1 <-> 2 <-> 3 -> null

Control flow statements in programming for decision making and looping

• if statement is used for conditional execution

• else statement is used with if to execute code when the condition is false

• break statement is used to exit a loop or switch statement

• switch statement is used to select one of many code blocks to be executed

Yes, I enjoy playing basketball and volunteering at a local coding club.

• I play basketball twice a week with a local league.

• I volunteer at a coding club for kids on weekends.

• I also participate in hackathons and attend tech meetups.

Spring MVC life cycle involves several phases from initialization to destruction of the application.

• Initialization of DispatcherServlet

• Processing of client request

• Handling of request by Controller

• View resolution and rendering

• Sending response to client

• Destruction of DispatcherServlet

Pseudocode for a basic DSA question

• Start by defining the problem statement and input/output requirements

• Identify the key data structures and algorithms needed to solve the problem

• Write step-by-step instructions in pseudocode to solve the problem

• Test the pseudocode with sample inputs to ensure correctness

The main difference between .NET Core and .NET Framework is that .NET Core is cross-platform and open-source, while .NET Framework is Windows-only and closed-source.

• NET Core is cross-platform, meaning it can run on Windows, macOS, and Linux, while .NET Framework is limited to Windows.

• .NET Core is open-source, allowing for community contributions and transparency, while .NET Framework is closed-source.

• .NET Core is modular, allowing developers to include only the necessary comp...read more

SQL query to find the 3rd highest salary in a table

• Use the ORDER BY clause to sort the salaries in descending order

• Use the LIMIT and OFFSET keywords to skip the first two highest salaries

• Example: SELECT salary FROM employees ORDER BY salary DESC LIMIT 1 OFFSET 2

Collections are data structures that store and manipulate groups of objects.

• Collections provide a way to organize and manage large amounts of data

• They can be used to perform operations on groups of objects, such as sorting or searching

• Examples of collections include arrays, lists, sets, and maps

Encapsulation is the concept of bundling data and methods that operate on the data into a single unit.

• Encapsulation helps in hiding the internal state of an object and restricting access to it.

• It allows for better control over the data by preventing outside interference.

• Encapsulation also promotes code reusability and modularity.

• Example: In object-oriented programming, a class encapsulates data (attributes) and methods (functions) that operate on that data.

Java is a high-level, object-oriented programming language used to develop applications for various platforms.

• Java is platform-independent, meaning it can run on any platform with a Java Virtual Machine (JVM)

• It is known for its security features and automatic memory management

• Java is used to develop a wide range of applications, from mobile apps to enterprise-level software

• Some popular Java frameworks include Spring, Hibernate, and Struts

I have a strong understanding of OOP concepts and have worked on various projects utilizing them.

• I have implemented inheritance, encapsulation, and polymorphism in my projects.

• For example, in a project for a banking system, I used inheritance to create different types of accounts with common functionalities.

• I have also used encapsulation to hide the implementation details of certain classes from other classes.

• In a project for a car rental system, I used polymorphism to allow ...read more

JPA stands for Java Persistence API, a specification for object-relational mapping in Java applications.

• JPA is used to map Java objects to relational database tables.

• It provides a set of annotations to define the mapping between Java classes and database tables.

• JPA also supports querying data using the Java Persistence Query Language (JPQL).

MVC architecture separates application into Model, View, and Controller components for efficient code flow.

• Model represents data and business logic

• View displays the data to the user

• Controller handles user input and updates the model and view accordingly

Print Fibonacci series upto n terms using iterative approach

• Initialize variables for first two terms of Fibonacci series

• Use a loop to calculate and print the next term based on previous two terms

• Continue the loop until n terms are printed

Equals compares the content of two strings, while == compares their references.

• Equals method checks if two strings have the same content.

• == operator checks if two strings refer to the same object in memory.

• Equals method is case-sensitive by default, but can be made case-insensitive.

• Example: String str1 = "hello"; String str2 = "hello"; str1.equals(str2) returns true, str1 == str2 returns true because of string interning.

• Example: String str1 = new String("hello"); String str2 ...read more

Multi-threading is the ability of a CPU to execute multiple threads concurrently, allowing for parallel processing.

• Allows for parallel execution of multiple tasks

• Improves performance by utilizing CPU resources efficiently

• Requires synchronization to prevent data corruption

• Examples: running multiple tasks simultaneously in a web server, video editing software