[Java] Introduction to Java

[Java] Introduction to Java

I even studied "sequential progress," "conditional branching," and "repetition."



class Hello {
    public static void main(String[] args){





class variable {
    public static void main(String[] arg){
        int var = 1;





class Array{
    public static void main(final String[] args) {
        int[] arr = new int[] { 8, 12, 21 };
         System.out.println("breakfast" + arr[0] + "From time");
         System.out.println("lunch" + arr[1] + "From time");
         System.out.println("Supper" + arr[2] + "From time");


Breakfast is from 8 o'clock
It's from 12:00 lunch
It's from 21:00 at night

Conditional branch


class Age{
    public static void main(String[] args){
      int humidity;
      humidity = 50;

      if (humidity >= 60){
        System.out.println("Humidity" + humidity + "%is");
        System.out.println("I'm messy");
      }else if((humidity <= 60) && (humidity >= 40)){
        System.out.println("Humidity" + humidity + "%is");
      }else if(humidity <= 40) {
        System.out.println("Humidity" + humidity + "%is");
        System.out.println("I'm crazy");



Humidity is 50%


Install JDK and editor VSCode on windows


This article was written with reference to the following information. Kinocode / YouTuber for programming learning videos

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