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Intro to Java (Intro to Java (Why use Java? (Java is more than a language)…

- - - - It comes packed with a huge library, reusable code, portability, and built-in security
        
        The library seems to be what sets Java apart
  - - - Simple
        
        Java stuck very closely to C++ but wanting a more simple language got rid of the poorly understood and unused features
        
        Along with being simple Java can be compact
        
        The library has grown huge but there are versions for embedded devices
      - Object-Oriented
        
        Just like C++, objects are extremely useful
      - Network-Savvy
        Robust
        Secure
        Architecture-Neutral
        Portable
        Interpreted
        Multithreaded
        High-Performance
        Dynamic
- - - - So what do these keywords mean
        
        public
        
        This is an access modifier
        
        It controls how much access other programs have with this class
        
        class
        
        Everything in Java happens inside a class
        
        For now view class as a container for your code
        
        After class always comes the name of the class
        
        Acceptable naming practice :checkered_flag:
        
        4 more items...
        
        main
        
        Java always starts execution in the main method
        
        main should always be public :!:
        
        static void
        
        For now just know we need it
        
        Remember that void means nothing needs to be returned to the method
        
        System.out
        
        This is an object and we use its println method to print a line then add the new character line
  - - - This is similar to const from C++
        
        This means once set you can't change the value of a variable that is final
    - - Sometimes it's more useful to have a final variable that can be used in multiple methods
        
        static final allows us to do that
        
        public class Constants2
        {
        public static final double CM_PER_INCH = 2.54;
        public static void main(String[] args)
        {
        double paperWidth = 8.5;
        double paperHeight = 11;
        System.out.println("Paper size in centimeters: "
        
        paperWidth CM_PER_INCH + " by " + paperHeight CM_PER_INCH);
        }
        }
        
        Notice that the static final is declared outside the main. This is what allows multiple methods to use it :!: