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Lucy Oleschuk
Level 31

The Most Challenging Topics in Learning Java

Published in the Learning Java group
First introduced in 1995, Java has become one of the most widely-used programming languages. This success is justified because Java is a platform-independent language running on over 3 billion devices with different operating systems. Among other strong points, Java attracts with its simplicity. As a result, Java is relatively easy to learn and deploy compared to many other programming languages. In addition, Java is friendly to beginners, being quick to learn if you put in the effort. The Most Challenging Topics in Learning Java - 1However, even the most diligent students may face difficulties. The most challenging topics and the best ways to "overcome" them are described below.

Why Does Java Seem Difficult for Beginners?

If you already have some technical background, learning Java may be a piece of cake for you. Yet, you may find it challenging to grasp if you're a complete newbie. The thing is that Java syntax is a statically-typed machine language with a wide variety of features and frameworks, not to mention it can be integrated into several platforms. So, what are the "hottest" topics for beginners?

Variable Visibility

Local variables can be a bit of a hustle for complete newbies (though a breeze for seasoned learners). In Java, local variables are extra helpful when we need a temporary variable to hold the values inside the block, and we don't need that variable(s) for other methods. Sounds tricky? You're not alone! That's why we have a lesson dedicated to local variables:

Result of a Method

What are the perks of using methods? For one, it's code reusability and for two, it's the fact that methods make code much more readable and easier to debug. However, you probably already know that the method might return to the code. It happens in three cases:
  • when it completes all the statements in the method,
  • when it throws an exception (covered later),
  • when it reaches a return statement.
If these aspects confuse you, then our lection about the return statements will come you in great handy:

When It Comes to Creating Your Methods

Of course, Java provides pre-defined methods, but if you create your methods, you'll open a new universe where you can perform certain actions tailored to your needs. In the following tutorial, you'll learn more about Java methods (how to define and use them) as well as how to create your ones with minimum effort and time put into it:

Method Parameters in Java

Simply put, parameters are variables defined within the method. Information can be passed to methods as parameters, which may include primitive types such as int, float, boolean, and so on (as well as non-primitive or object types such as an array, String, etc.). To find out more about this topic, you may refer to the following lecture:


Another complex topic for fresh learners is ArrayList. Being a part of the collection framework, ArrayList is used in Java to store a dynamically sized collection of elements. It's an element of Java's collection framework that implements Java's List interface. To get familiarity with this topic, you may refer to our lecture:

Arrays Class

The next topic that may frustrate you is the Arrays class and its use. The Arrays class is a part of the Java Collection Framework. This class contains different methods for manipulating arrays (sorting and searching). Also, it includes a static factory that allows arrays to be viewed as lists. Arrays class consists of only static methods and the methods of Object class. The dedicated article along with the lesson, will make things much easier and more understandable for you.

Objects and Classes

An entity with a state, behavior, and identity is an object in Java. An object is an instance of a class. A class is a group of objects that have common properties. It's a template from which objects are created. Hence, an object is the instance (result) of a class. Sounds quirky? You're not alone. The following lessons can help shed light on ways to initialize objects, how to create objects in Java, and many more:

Constructors and Their Peculiarities

Generally, constructors in Java can be divided into No-Arg constructors, Parameterized constructors, and Default constructors. These constructors may or may not have any parameters (arguments) similar to methods. In addition, some of them can also accept one or more parameters. Not surprisingly, this topic may be incredibly confusing for beginners. Therefore, we have a few lessons targeted toward constructors and their specific features:


Inheritance is a potent tool for creating OO structures. It's an essential mechanism in Java, allowing you to inherit another class's features (fields and methods). However, when not used properly, it can create a very tightly coupled code and is hard to maintain. Inheritance has gathered a pretty fearsome reputation because of this. And to help students get the hang of using it correctly, we have prepared an extensive lesson and article:


Not without reason, many fresh learners get stuck in the Static classes, Static methods, and Static Variables. Why are static variables considered evil? Whereas some believe that "They are contrary to the object-oriented paradigm. In particular, it violates the principle that data is encapsulated in objects (that can be extended, information hiding, etc.)" whereas others believe that "Static variables represent the global state. That's hard to reason about and hard to test". Our comprehensive topics will help you overcome difficulties with static variables and make you love them, not hate:That just being said, some other concepts can make your brain melt. For example, Generics appears to be one of the most head-cranking parts for many learners. Others mention that multi-thread concepts, native interface, polymorphism, Apt implementation of Synchronization and Serialization, and usage of Vectors and Matrix are also those aspects that you are likely to grapple with.


Java is vast, and there could be many aspects that could be harassing someone. But, with that, Java is flexible, and there are many ways to solve the same challenge. So, if you get stuck, try thinking about other steps to solve the problem. Java is fun, and its code challenges can help you become more skillful and self-confident. Remember that if you are a complete newbie in the IT world, learning the basics of Java is the first step. But another great move is to connect with seasoned developers and fellow Java learners like you. Of course, CodeGym will help you go through the most challenging topics, but if you hit a dead-end, Java communities can be beneficial. And finally, the last component of successful learning is practice. If you want to learn Java programming quickly and easily, taking a lot of practice coding is extra helpful. For a dedicated person (with no prior programming experience), it may take just 9-12 months to understand Java and begin writing programs completely. So, let's get down to practice!
Comments (1)
Hoist Level 29, San Diego, United States
7 October 2022
Yet another worthwhile read from a codegym ! Tons of articles on complex topics made so much easier to comprehend and make useful.