Alpha IT Web Solutions Interview Questions and Answers

Database is crucial for storing and managing data in backend development.

• Database stores and organizes data for efficient retrieval and manipulation.

• It allows for easy querying and filtering of data.

• It enables data consistency and integrity through constraints and validations.

• It facilitates data migration and backup.

• Examples include MySQL, MongoDB, and PostgreSQL.

Java is a compiled language that also uses interpretation at runtime.

• Java code is compiled into bytecode which is then interpreted by the Java Virtual Machine (JVM) at runtime.

• This allows Java to be platform-independent as the bytecode can be executed on any system with a JVM.

• However, some modern JVMs also use just-in-time (JIT) compilation to improve performance.

• JIT compilation compiles bytecode into native machine co...read more

Polymorphism is the ability of an object to take on many forms.

• It allows objects of different classes to be treated as if they were objects of the same class.

• It is achieved through method overloading and method overriding.

• Example: A shape class can have different subclasses like circle, square, and triangle, each with their own implementation of the draw method.

• Polymorphism makes code more flexible and reusable.

The 'implements' keyword is used to indicate that a class is implementing an interface.

• The 'implements' keyword is followed by the name of the interface that the class is implementing.

• A class can implement multiple interfaces by separating them with commas.

• All methods declared in an interface must be implemented by the class that implements it.

• Example: 'public class MyClass implements MyInterface { ... }'