S. Soni & Co. Interview Questions and Answers

Count the occurrence of each word in a given string and store it in a map.

• Split the string into words using whitespace as delimiter

• Create a map to store the word count

• Iterate through the words and update the count in the map

• Return the map

Class not found and no class definition found exception occurs when a required class is not found during runtime.

• This exception occurs when the JVM tries to load a class but cannot find it in the classpath.

• It can happen if the class is missing from the project dependencies or if the classpath is not properly configured.

• Check if the class is present in the correct package and if it is included in the project dependencies.

• Verify the classpath settings and ensure that all requir...read more

Java 8 introduced several new features including lambda expressions, streams, and default methods.

• Lambda expressions for functional programming

• Streams for efficient processing of large data sets

• Default methods to add new functionality to interfaces

• Date and Time API for improved handling of date and time

• Nashorn JavaScript engine for improved performance

• Parallel array sorting for faster sorting of large arrays

Singleton class is a class that allows only one instance of itself to be created and provides a global point of access to it.

• Singleton class restricts the instantiation of a class to a single object.

• It is used when only one instance of a class is required to control actions throughout the system.

• The Singleton pattern is implemented by creating a class with a method that creates a new instance of the class if one doesn't exist and returns it if it does.

• The constructor of the S...read more

Design patterns are reusable solutions to common software development problems.

• Design patterns provide a common language for developers to communicate about solutions to common problems.

• They can improve the quality, maintainability, and scalability of software.

• Examples include the Singleton pattern, Factory pattern, and Observer pattern.

• Design patterns can be categorized into three groups: creational, structural, and behavioral patterns.

JVM is an environment to run Java programs, JRE is a runtime environment, and JDK is a development kit.

• JVM stands for Java Virtual Machine and is responsible for executing Java bytecode.

• JRE stands for Java Runtime Environment and provides a runtime environment for Java programs.

• JDK stands for Java Development Kit and includes tools for developing Java applications.

• JDK includes JRE and additional development tools such as compilers and debuggers.

• JVM is platform-dependent, whil...read more

Annotations are used in Spring Boot for various purposes such as mapping requests, defining beans, and handling exceptions.

• Annotations are used to provide metadata to the Spring framework.

• They are used to map requests to controller methods using @RequestMapping.

• Annotations like @Component, @Service, and @Repository are used to define beans.

• Annotations like @ExceptionHandler and @ControllerAdvice are used for handling exceptions.

• Annotations like @Autowired and @Value are used ...read more