Comprehensive Java Roadmap.

1. Basics of Java

• Introduction to Java
  • What is Java?
  • Setting Up the Development Environment (JDK, IDEs like IntelliJ IDEA, Eclipse)
• Basic Syntax
  • Hello World Program
  • Understanding Java's Structure (Classes, Methods)
• Variables and Data Types
  • Variable Declaration and Initialization
  • Primitive Data Types (int, float, char, boolean, etc.)
  • Non-Primitive Data Types (String, Arrays, Classes)
• Operators
  • Arithmetic, Assignment, Comparison, Logical, Bitwise

2. Control Structures

• Conditional Statements
  • If, Elseif, Else, Switch
• Loops
  • For, While, Do...While
  • Break, Continue

3. Object-Oriented Programming (OOP)

• Classes and Objects
  • Defining Classes, Creating Objects
• Attributes and Methods
  • Instance Variables, Class Variables, Methods
• Constructors
  • Default and Parameterized Constructors
• Inheritance
  • Single Inheritance, Method Overriding, Using super
• Polymorphism
  • Method Overloading, Method Overriding
• Encapsulation
  • Access Modifiers (public, private, protected), Getters and Setters
• Abstraction
  • Abstract Classes, Interfaces

4. Advanced OOP Concepts

• Inner Classes
  • Static and Non-static Inner Classes
• Anonymous Classes
  • Implementing Anonymous Classes
• Enums
  • Defining and Using Enums

5. Exception Handling

• Basics of Exceptions
  • Try, Catch, Finally
• Custom Exceptions
  • Creating and Throwing Custom Exceptions
• Common Exceptions
  • NullPointerException, ArrayIndexOutOfBoundsException, etc.

6. Java Collections Framework

• Introduction to Collections
  • List, Set, Map Interfaces
• ArrayList and LinkedList
• HashSet and TreeSet
• HashMap and TreeMap
• Iterators and Enhanced for Loop

7. Streams and File I/O

• File Handling
  • Reading and Writing Files
  • File Class and Methods
• Streams
  • Byte Streams, Character Streams
• Serialization
  • Serializing and Deserializing Objects

8. Generics

• Introduction to Generics
  • Generic Classes, Methods, and Interfaces
• Type Parameters and Wildcards
  • Bounded Type Parameters, Wildcard Parameters

9. Multithreading and Concurrency

• Introduction to Threads
  • Creating Threads (Extending Thread Class, Implementing Runnable Interface)
• Thread Lifecycle
  • Thread States, Methods (start, run, sleep, join)
• Concurrency
  • Synchronization, Locks, Executor Framework

10. Java 8+ Features

• Lambda Expressions
  • Syntax and Functional Interfaces
• Streams API
  • Creating and Processing Streams
• Optional Class
  • Avoiding NullPointerExceptions
• Date and Time API
  • Working with LocalDate, LocalTime, LocalDateTime

11. Database Connectivity

• JDBC Basics
  • Setting Up JDBC, Connecting to a Database
• CRUD Operations
  • Creating, Reading, Updating, Deleting Records
• Prepared Statements
  • Using Prepared Statements for Secure Database Access

12. Web Development

• Servlets and JSP
  • Introduction to Servlets, Creating and Deploying Servlets
  • JSP Basics, Using JSP with Servlets
• Frameworks
  • Introduction to Spring Framework, Spring Boot
  • Basics of RESTful Web Services

13. Testing

• Unit Testing
  • Using JUnit for Unit Tests
• Mocking
  • Using Mockito for Mocking Dependencies
• Integration Testing

14. Build Tools and Dependency Management

• Maven
  • Setting Up Maven, POM File, Managing Dependencies
• Gradle
  • Introduction to Gradle, Build Scripts

15. Best Practices

• Code Quality
  • Writing Clean and Maintainable Code
  • Using Static Analysis Tools (SonarQube)
• Design Patterns
  • Singleton, Factory, Observer, etc.
• Version Control
  • Using Git for Version Control, GitHub/GitLab Integration

16. Deployment and Maintenance

• Packaging Java Applications
  • Creating JAR/WAR Files
• Continuous Integration/Continuous Deployment (CI/CD)
  • Using Jenkins, GitHub Actions

17. Continuous Learning

• Staying Updated
  • Following Java Enhancement Proposals (JEPs), New Releases
• Learning Resources
  • Official Documentation, Online Courses, Community Forums

This comprehensive roadmap provides a structured approach to mastering Java, from basic concepts to advanced techniques. Adjust the roadmap according to your learning pace and goals. Happy coding