Interview Questions
DB Interview Questions
Databases What is a “database”? What is a “database management system”? What is a “relational data model”? Define the terms “simple”, “composite”, “candidate”, and “alternate” key. What is a “primary key”? What are the criteria for its selection? What is a “foreign key”? What is “normalization”? What normal forms exist? What is “denormalization”? What is it applied for? What types of relationships exist in a database? Provide examples. What are “indexes”?
Understanding Servlets, JSP, and JSTL for Interview Preparation
An extensive guide on Servlets, JSP, and JSTL with common interview questions and answers.
JDBC Interview Questions
JDBC What is JDBC? What are the advantages of using JDBC? What is a JDBC URL? What components make up JDBC? List the main classes and interfaces in JDBC. Describe the main steps for working with the database using JDBC. List the main data types used in JDBC. How are they related to Java types? How do you register a JDBC driver? How do you establish a connection to a database?
Java Collections Framework
Interview Questions Java Collections Framework What is a “collection”? Name the main interfaces of the JCF and their implementations. Arrange the following interfaces in a hierarchy: List, Set, Map, SortedSet, SortedMap, Collection, Iterable, Iterator, NavigableSet, NavigableMap. Why is Map not a Collection, while List and Set are Collection? What is the difference between java.util.Collection and java.util.Collections? What is “fail-fast behavior”? What is the difference between fail-fast and fail-safe? Provide examples of iterators that implement fail-safe behavior.
Design Patterns
Design Patterns What is a “design pattern”? Name the main characteristics of design patterns. Types of design patterns. Provide examples of main design patterns. Provide examples of creational design patterns. Provide examples of structural design patterns. Provide examples of behavioral design patterns. What is an “anti-pattern”? What anti-patterns do you know? What is Dependency Injection? What is a “design pattern”? A design pattern is a proven and ready-to-use solution. It is not a class or a library that can be plugged into a project; it’s something more than that – it is language-independent, not a finished example that can be directly converted into code, and it can be implemented in different ways across various programming languages.
Logging
Interview Questions Interview Questions Logging What types of logs exist? What are the components of the log4j logging system? What is a Logger in log4j? What is an Appender in log4j? What is a Layout in log4j? List the logging levels in log4j. What is their priority order? What configuration methods exist for log4j? What types of logs exist? System; Security; Application (Business). A user logs into the application, and their password is verified.