Some basics about java

1. Real-world objects contain state and behavior.
2. A software object's state is stored in fields.
3. A software object's behavior is exposed through methods.
4. Hiding internal data from the outside world, and accessing it only through publicly exposed methods is known as data encapsulation.
5. A blueprint for a software object is called a class.
6. Common behavior can be defined in a superclass and inherited into a subclass using the extends keyword.
7. A collection of methods with no implementation is called an interface.
8. A namespace that organizes classes and interfaces by functionality is called a package.
9. The term API stands for Application Programming Interface.

Reverse string in java

Simplest Example of making reverse string using java

public class StringReverse
{
  public static void main(String[] args)
  {
  String string=args[0];
  String reverse = new StringBuffer(string).
reverse().toString();
  System.out.println("\nString before reverse:
"+string);
  System.out.println("String after reverse:
"+reverse);
  } 
}