Pollution Protection Systems Interview Questions and Answers

Explanation of Java features, Stream API, microservices, HTTP vs HTTPS, and SQL joins.

• Lambda expressions allow for concise syntax to implement functional interfaces.

• Stream API provides a way to process collections of objects in a functional style.

• Microservices architecture breaks down applications into smaller, independent services.

• HTTP is unencrypted protocol, HTTPS is encrypted using SSL/TLS for secure communication.

• Inner join combines rows from two tables based on a relate...read more

Answers to common Java Spring Boot Developer interview questions.

• Java8 features include lambda expressions, functional interfaces, streams, and default methods.

• String is immutable in Java to ensure thread safety and prevent unintended modifications.

• Checked exceptions are checked at compile time, while unchecked exceptions are not. Example: IOException vs NullPointerException.

• throw is used to explicitly throw an exception, while throws is used to declare that a method may thro...read more

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

• Singleton classes are often used in Spring Boot for managing resources such as database connections or thread pools.

• In Spring Boot, singleton beans are created by default, meaning that only one instance of a bean is created and shared across the application.

• To create a singleton bean in Spring Boot, you can use the @Component annotation or ...read more

The question covers topics like method overriding, method overloading, exceptions, Java 8 features, and string manipulation.

• Method overriding is when a subclass provides a specific implementation of a method that is already provided by its superclass.

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

• Exception handling is used to handle errors that occur during the execution of a program.

• Java 8 introduced features like lambda expressions, ...read more

Rest controllers are specifically used for RESTful web services, while normal controllers are used for traditional web applications.

• Rest controllers are used to build RESTful web services that can accept and return JSON or XML data.

• Normal controllers are used for traditional web applications that render HTML views.

• Rest controllers use annotations like @RestController and @RequestMapping to define endpoints.

• Normal controllers use annotations like @Controller and @GetMapping to...read more

Memory leak is a situation where a program uses memory inefficiently, causing memory to be allocated but not released.

• Memory leak occurs when a program allocates memory but does not release it after it is no longer needed.

• Identifying memory leaks can be done using tools like profilers to analyze memory usage over time.

• Common signs of memory leaks include increasing memory usage over time, frequent garbage collection, and application crashes due to out-of-memory errors.

Stateless API does not store client state on the server, while stateful API does.

• Stateless API: Each request from client to server must contain all necessary information for the server to fulfill the request. No client state is stored on the server. Example: RESTful APIs.

• Stateful API: The server stores client state, which can be accessed by subsequent requests. Example: HTTP sessions.