Infinite Computer Solutions Java Developer Interview Questions and Answers

Qualifier and Primary are annotations used in Spring framework for dependency injection.

• Qualifier annotation is used to specify which bean should be autowired when multiple beans of the same type are present

• Primary annotation is used to specify the primary bean to be autowired when multiple beans of the same type are present

• Qualifier can be used in combination with Autowired annotation to specify the bean name to be in...read more

Sort an array of 0s and 1s in linear time complexity.

• Use two pointers approach - one from the start and one from the end.

• Swap 0s to the left and 1s to the right until the pointers meet.

• Time complexity: O(n), Space complexity: O(1).

I actively participate in code reviews to ensure code quality and learn from others.

• I actively participate in code reviews by providing constructive feedback on others' code.

• I also seek feedback on my own code to improve its quality and learn from others.

• I follow coding standards and best practices during code reviews to maintain consistency and quality.

• I use code review tools like GitHub pull requests or Bitbucket to

Developed a web-based inventory management system for a retail company.

• Used Java, Spring Boot, and MySQL for backend development.

• Implemented user authentication and authorization using Spring Security.

• Designed a responsive front-end using HTML, CSS, and JavaScript.

• Integrated barcode scanning functionality for efficient inventory tracking.

A class is a blueprint or template for creating objects, while an object is an instance of a class.

• A class defines the properties and behaviors of objects, while an object is a specific instance of a class.

• Classes can be used to create multiple objects with similar characteristics.

• Objects have state (attributes) and behavior (methods) defined by the class.

• Example: Class 'Car' defines properties like 'color' and 'model'...read more

Comparable is an interface used for natural ordering, while Comparator is used for custom ordering in Java.

• Comparable interface is used to define the natural ordering of objects. It is implemented by the class whose objects are to be sorted.

• Comparator interface is used to define custom ordering of objects. It is implemented by a separate class that compares objects based on specific criteria.

• Example: Sorting a list of ...read more

List allows duplicate elements and maintains insertion order, while Set does not allow duplicates and does not maintain order.

• List can contain duplicate elements, Set cannot

• List maintains insertion order, Set does not guarantee order

• List is implemented by classes like ArrayList, LinkedList, Set is implemented by classes like HashSet, TreeSet

• Example: List list = new ArrayList<>(); Set set = new HashSet<>();