Learn Java on Your Own in 20 Days- Free

When it comes to software development. Few tools are as dynamic and powerful as Java -- ideal for both small and industrial scale projects alike. Its versatility enables developers to create an extensive range of applications and systems with ease: from simple mobile apps all the way up to intricate company wide software solutions. However, If taking formal training courses isn't feasible or desirable for you right now but learning Java is still something that interests you greatly -- don't worry! There are numerous free resources accessible online that allow self learners like yourself to become proficient in no more than 20 days.

Day 1-2 (Fundamentals)

The key to understanding programming languages like JAVA lies in developing an extensive comprehension of their nature and components.With that said,dive into it by delving into introductory material that explores the language itself along with its potential applications.Next up,double check to ensure proper configuration setups before trying out your hand at creating,gathering,tweaking code lines.An added advantage of this method is improving one's knowledge on syntax as well as discovering highly resourceful Integrated Development Environments.

• Introduction to Java and It’s Features

• Java Virtual Machine (JVM)

• Setting up the Java Environment

• Hello World Program in Java

• Integrated Development Environments (IDEs) for Java

Day 2-3 (Data Types, Variables and Conditional Statements)

Becoming a proficient programmer requires mastering a few essential concepts. Understanding variables, modifiers, operators and loop statements in JAVA is crucial before exploring language-specific subjects. Once the fundamentals are clear, one can gain more insight into this field by attempting basic programs to assess their level of understanding. Remember: the key to successful programming is a good dose of perplexity and burliness.

• Data Types

• Variables

• Conditional Statements

• Loops in Java

• Modifiers

• Operators

• Programs: Swapping of Numbers, Factorial, Fibonacci Series, etc.

Day 4-5 (Arrays and String Manipulation)

With arrays, strings, and other concepts, learning JAVA can be a confusing task. However, taking a step forward and learning them can be so rewarding. Working with arrays in JAVA has many modest differences compared to C/C++ - as they are dynamically allocated and have some additional features as well. To further one's understanding, type conversions, variable scopes, and other tips can be explored. To truly master any language and be able to bridge the gap between theory and application, it is essential to understand the basics and the finer details.

• Arrays

• Strings

• Array VS Array List in Java

• Scope of Variables

• Type conversion in Java

• Switch statement in Java

Day 6-8 (Objects, Classes and Methods)

To become fluent in programming using the Java language requires developing a clear grasp on its essential components first-hand thoroughly. This necessitates becoming proficient in understanding concepts like classes and objects since doing so allows us to discern their indistinct properties more effectively.Incorporating knowledge about using approaches like method construction and further interpretation is also a critical aspect of acquiring Java programming proficiency. Constructors represent key components when working with Java programs, so devoting time towards comprehending their workings as well would be wise. Fully comprehending and mastering these essential building blocks is a prerequisite for unlocking the intricate complexities present within the inner machinations of Java programming.

• Classes

• Objects

• Methods

• Method Overloading

• Method Overriding

• Parameter Passing in Java

• Constructors in Java

Day 9-10 (OOPs Concept)

JAVA is an Object-Oriented Programming language which puts forth complex principles such as polymorphism, inheritance, encapsulation and abstraction. Mastering these paradigms is essential to become a proficient JAVA coder and to make focused progress in topics like overloading, overriding and more. A robust grasp on the core concepts can feel intimidating but is pivotal for both comprehensive understanding and successful programming. Achieving maximum potential with JAVA requires investing experienced dedication into finding an intimate familiarity with its workings, which includes extensive exploration into Object-Oriented Programming (OOPs) principles.

• Inheritance

• Encapsulation

• Polymorphism

• Runtime Polymorphism

• Abstraction

• Super Keyword

• Association, Composition and Aggregation

Day 11-13 (Interfaces and Packages)

Java programming offers an in-depth exploration of a variety of topics such as interfaces, packages, abstract classes, and nested interfaces. Interfaces can contain methods and variables, however, by default all methods declared are abstract. Packages encapsulate a group of classes, sub-packages and interfaces. An examination into the discrepancies between Javas' interfaces and abstract classes exposes slight distinctions in their underlying concepts. Notably where an interface is limited to purely containing entirely abstract approaches an internal class affords some degree of adaptability by allowing both concrete and symbolic techniques to be defined therein. Individuals looking to gain a better grasp on these subtleties are encouraged to take a closer look at such ideas within the realm of Java programming.

• Interfaces

• Packages

• Nested Interface

• Marker Interface

• Abstract Class

• Difference between Abstract class and Interfaces

• Java.Time, Java.lang, Java.Math and other packages

Day 14-16 (Exception Handling, I/O Streams and Multi-threading)

There are several principles to become familiar with, such as Exception Handling for dealing with exceptions and warnings, multi-threading for the concurrent execution of two or more parts of the program, I/O Streams for input and output streams in Java, and Regular Expressions (Regex) which define String patterns used for searching, manipulating, and editing text. These topics are charged with complexity and diverse in application, creating a wide range of possible approaches and techniques. As such, one can approach Exception Handling, for instance, by exploring the topic to uncover the numerous techniques that come with it; or one can take a more structured approach and learn the processes and methods necessary to understand it in its entirety. Similarly, when it comes to multi-threading, it offers countless avenues for learning the concurrent execution of parts of a program, such as methods for managing the processor, diminishing latency, or optimizing the performance.

To reach the highest level of proficiency in using the language, understanding the basics, experimenting with various approaches, and obtaining the tactical knowledge necessary to handle any situation are all important steps. Through gaining an understanding of Exception Handling, Multi-threading, I/O Streams, and Regular Expressions, any JAVA programmer can be sure to develop the skills and know-how needed to excel.

• Exception Handling

• Types of Exceptions

• Multi-threading

• Regular Expressions

• File Handling

Day 17-20 (Collection Framework, AWT & SWING)

With implementation aspects of all the concepts and theoretical knowledge discussed in the previous sections, it is essential to become acquainted with the Collection Framework, a set of classes and interfaces which represent a group of objects as a single unit. Moreover, one has to gain proficiency with the Abstract Window Toolkit (AWT) and the Swing in Java to be able to take up various small or large projects featuring GUI (Graphical User Interface).

• Collections in Java

• Generics in Java

• Java Swing

• Java Calculator

• Java AWT

• Java Projects

Conclusion

If you want to get really deep into Java programming, you're going to need a clear road map. Difficult but doable – if you plan right. To cover the entire Java curriculum, split the work: dedicate two topics per day and you'll master the language in just 20 days. All you need is some hard work and devotion. So why wait? Start digging into Java and let your passion guide you through the journey!