30+ BigBasket Interview Questions and Answers

Code to filter out loans with incomplete status using Java 8 features.

• Use stream() method to convert the list of loans into a stream

• Use filter() method to filter out loans with incomplete status

• Use collect() method to collect the filtered loans into a new list

Java is an object-oriented programming language. Inheritance is a mechanism to create new classes based on existing ones. OOPs is a programming paradigm. Method is a block of code that performs a specific task.

• Java is a high-level, class-based, and object-oriented programming language.

• Inheritance is a mechanism in which one class acquires the properties and behaviors of another class.

• OOPs is a programming paradigm that focuses on objects and their interactions.

• Method is a blo...read more

Polymorphism is the ability of an object to take on multiple forms. It can be achieved through method overloading and overriding.

• Method overloading is when multiple methods have the same name but different parameters. The compiler decides which method to call based on the arguments passed.

• Method overriding is when a subclass provides its own implementation of a method that is already present in its parent class. The method signature remains the same.

• Polymorphism allows for co...read more

Yes, Java is an object-oriented language.

• Java supports all the features of object-oriented programming such as encapsulation, inheritance, and polymorphism.

• All code in Java is written inside classes, which are objects.

• Java also has interfaces, which allow for multiple inheritance.

• Example: Java's String class is an object that has methods and properties.

• Example: Inheritance in Java allows a subclass to inherit properties and methods from a superclass.

Answering questions related to Actuator, Dependency Injection, changing embedded server in Spring Boot, and permutation of string.

• Actuator is a Spring Boot feature that provides endpoints for monitoring and managing the application.

• Dependency Injection is a design pattern that allows objects to be created with their dependencies injected from outside.

• To change the embedded server in Spring Boot, you can exclude the default server dependency and add a new one.

• Permutation of st...read more

Java is an object-oriented programming language. OOPs concepts include inheritance, encapsulation, polymorphism, and abstraction.

• Java is a high-level programming language that is platform-independent.

• OOPs concepts are the foundation of Java programming.

• Inheritance is a mechanism in which one class acquires the properties and behaviors of another class.

• A method is a collection of statements that perform a specific task.

• Examples of OOPs concepts in Java include encapsulation, p...read more

Java is an object-oriented programming language. Method is a block of code that performs a specific task. OOPs concepts are principles of object-oriented programming.

• Java is a high-level programming language that is platform-independent.

• Method is a block of code that performs a specific task and can be called multiple times.

• OOPs concepts include inheritance, encapsulation, polymorphism, and abstraction.

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

Java is a programming language. Method is a block of code that performs a specific task. OOPs is a programming paradigm.

• Java is an object-oriented programming language used to develop applications and software.

• A method is a block of code that performs a specific task and can be called by other parts of the program.

• OOPs is a programming paradigm that focuses on objects and their interactions to solve problems.

• OOPs concepts include encapsulation, inheritance, polymorphism, and ...read more

I would rate myself as an 8 in Java.

• I have extensive experience in Java programming and have successfully completed multiple projects using Java.

• I am familiar with various Java frameworks and libraries.

• I have a strong understanding of object-oriented programming principles in Java.

• I am comfortable working with Java's core features and APIs.

• I continuously strive to improve my Java skills through self-learning and staying updated with the latest developments in the Java ecosyst...read more

Final, Finally, Finalize() are keywords in Java used for different purposes.

• Final is used to declare a variable as constant.

• Finally is used to execute a block of code after try-catch block.

• Finalize() is a method used for garbage collection.

• Final can be used with classes, methods, and variables.

• Finally block is always executed whether an exception is thrown or not.

The jQuery ajax GET request syntax is used to send an HTTP GET request to a server and retrieve data.

• Use the $.ajax() method with the 'type' parameter set to 'GET'

• Specify the URL of the server endpoint as the 'url' parameter

• Handle the response using the 'success' callback function

• Optionally, pass data to the server using the 'data' parameter

Functional Interface is an interface with only one abstract method. Flat Map is used to flatten nested collections. Method Reference is a shorthand notation for lambda expressions. Stream API is used to process collections of objects.

• Functional Interface is an interface with a single abstract method, such as Runnable or Comparator.

• Flat Map is a method in Java that is used to flatten nested collections, like List> to List.

• Method Reference is a shorthand notation for lambda exp...read more

In case of order failure with payment deducted, refund the payment and investigate the issue.

• Initiate refund process for the deducted payment

• Investigate the reason for the order failure

• Communicate with the customer about the issue and resolution

• Ensure the payment gateway is functioning correctly to prevent future occurrences

Annotations in Spring Boot are used to provide metadata about the code. @SpringBootApplication is a meta-annotation that combines @Configuration, @EnableAutoConfiguration, and @ComponentScan.

• Annotations in Spring Boot are used to simplify configuration and reduce boilerplate code.

• @SpringBootApplication is a meta-annotation that enables the auto-configuration feature in Spring Boot.

• It combines @Configuration, @EnableAutoConfiguration, and @ComponentScan annotations.

• Example: @S...read more

Establish a JDBC connection and fetch results from a database using Java.

• Import the necessary JDBC packages

• Load and register the JDBC driver

• Establish a connection to the database

• Create a statement object

• Execute a query to fetch results

• Iterate over the result set and print the results

• Close the result set, statement, and connection

Static variables are variables that belong to the class itself, rather than an instance of the class.

• Static variables are declared using the 'static' keyword.

• They are shared among all instances of the class.

• They can be accessed without creating an object of the class.

• Static variables are initialized only once, at the start of the program.

• They are useful for storing data that is common to all instances of a class.

To write a custom exception in Java, create a new class that extends Exception or a subclass of Exception.

• Create a new class that extends Exception or a subclass of Exception.

• Add a constructor to the custom exception class to pass a message to the superclass constructor.

• Throw the custom exception using the 'throw' keyword in your code.

• Handle the custom exception using try-catch blocks or propagate it up the call stack.

Functional interfaces are interfaces with only one abstract method, used for functional programming in Java.

• Functional interfaces can have multiple default or static methods, but only one abstract method.

• They are used in lambda expressions and method references for functional programming.

• Examples include java.lang.Runnable, java.util.Comparator, and java.util.function.Function.

Program to find missing element from array of strings

• Iterate through the array and store elements in a HashSet

• Iterate through another array and check if each element is present in the HashSet

• Return the element that is not present in the HashSet

Using lambda expressions in Java 8 to print a message

• Use the lambda syntax (parameters) -> { body } to define the behavior

• Example: () -> System.out.println("Hello, World!")

Constructors are special methods used to initialize objects in Java.

• Constructors have the same name as the class and do not have a return type.

• Types of constructors include default constructor, parameterized constructor, and copy constructor.

• Default constructor is provided by Java if no constructor is defined.

• Parameterized constructor takes parameters to initialize an object with specific values.

• Copy constructor creates a new object by copying the values of an existing object...read more

Volatile keyword in Java is used to indicate that a variable's value will be modified by different threads.

• Volatile keyword ensures visibility of changes made by one thread to other threads.

• It prevents compiler optimizations that could reorder code and cause unexpected behavior in a multi-threaded environment.

• Volatile variables are not cached in thread's local memory, but always read from main memory.

• Example: 'volatile boolean flag = true;'

Strong OOPS concept is essential for Java developers to write efficient and maintainable code.

• Understanding of classes, objects, inheritance, polymorphism, and encapsulation

• Ability to design and implement complex systems using OOPS principles

• Experience with design patterns and SOLID principles

• Knowledge of interfaces, abstract classes, and access modifiers

• Familiarity with UML diagrams for modeling software systems

A functional interface is an interface that contains only one abstract method and can be used as a lambda expression.

• Functional interfaces can have multiple default or static methods, but only one abstract method.

• Examples of functional interfaces in Java include Runnable, Callable, and ActionListener.

• Functional interfaces are often used with lambda expressions to provide a concise way of implementing single abstract method interfaces.

A daemon thread is a low priority thread that runs in the background and does not prevent the JVM from exiting when all user threads have finished.

• Daemon threads are used for tasks that need to run continuously in the background, such as garbage collection.

• They are automatically terminated by the JVM when all user threads have finished execution.

• To create a daemon thread in Java, you can call the setDaemon(true) method on a Thread object before starting it.

Use stream to get 2nd highest salary in Java

• Sort the salaries in descending order using stream

• Skip the first salary to get the second highest salary

FlatMap is a method in Java that transforms each element of a stream into a new stream and then concatenates all the streams into a single stream.

• FlatMap is used to flatten nested collections or maps into a single collection.

• It is commonly used in Java streams to process and transform data efficiently.

• Example: List> nestedList = Arrays.asList(Arrays.asList(1, 2), Arrays.asList(3, 4)); nestedList.stream().flatMap(List::stream).forEach(System.out::println);

Stream API is a feature in Java that allows processing collections of objects in a functional style.

• Stream API provides a way to perform operations on collections like filter, map, reduce, etc.

• It supports functional programming paradigms like lambda expressions and method references.

• Example: List names = Arrays.asList("Alice", "Bob", "Charlie"); Stream stream = names.stream();

HashMap is a data structure that stores key-value pairs and uses hashing to efficiently retrieve values.

• HashMap internally uses an array of linked lists to store key-value pairs.

• When a key-value pair is added, the key is hashed to find the index in the array where it will be stored.

• If multiple keys hash to the same index, a linked list is used to handle collisions.

• To retrieve a value, the key is hashed again to find the index and then the linked list is traversed to find the ...read more

JRE stands for Java Runtime Environment, it is a software package that provides the necessary tools to run Java applications.

• JRE includes Java Virtual Machine (JVM), class libraries, and other necessary files to run Java applications.

• It does not contain development tools like compiler or debugger, which are included in JDK (Java Development Kit).

• JRE is required to run Java applications on a computer, as it provides the environment for executing Java code.

• Examples of JRE imple...read more

JDK stands for Java Development Kit, it is a software development kit used for developing Java applications.

• JDK includes tools for developing, debugging, and monitoring Java applications.

• It contains JRE (Java Runtime Environment) which is necessary for running Java programs.

• JDK also includes a compiler, debugger, and other tools needed for Java development.

• Examples of JDK versions include JDK 8, JDK 11, and JDK 15.

SDLC stands for Software Development Life Cycle, a process used to design, develop, and test software applications.

• SDLC is a structured process that includes planning, designing, coding, testing, and deployment of software.

• Common SDLC models include Waterfall, Agile, and DevOps.

• Each phase of SDLC has specific goals and deliverables to ensure the quality and success of the software project.

Spring Boot simplifies the development of Java applications by providing a set of tools and conventions.

• 1. Rapid development: Spring Boot reduces the amount of boilerplate code needed, allowing developers to quickly build and deploy applications.

• 2. Opinionated defaults: Spring Boot provides sensible defaults for configuration, reducing the need for manual setup.

• 3. Embedded servers: Spring Boot includes embedded servers like Tomcat, Jetty, or Undertow, making it easy to run ap...read more