Check out example codes for "what is java". It will help you in understanding the concepts better.

Code Example 1

Java is dynamic. It’s an object oriented programming language.
architecture-neutral. Because applications written in java are convenient 
across many platforms.

Code Example 2

Java is a general-purpose programming language that is 
class-based, object-oriented, and designed to have as 
few implementation dependencies as possible.

Hello World in Java:
public class FileName {
  public static void main(String args[]) {
    System.out.println("Hello World!");
  }
}

Code Example 3

abstract class scratch{
  
}

Code Example 4

public abstract class GraphicObject {

   abstract void draw();
}

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