how to start java program code example

Example 1: cmd java compile

javac MyFisrtProgam.java // enter to compile 
  java MyfirstProgram // run program

Example 2: java run project from command line

// Assuming that you have an executable jar
java -jar myJavaProject.jar

// Assuming that you have packaged jar
java -jar target/myJavaProject.jar

Example 3: how to start a java program

class A {
 public static void main(String args[]){
     System.out.println("Hello World");
 }
}