Hello World
In Java, everything goes into a class, into a file with .java extension.
/**
* In Java, everything goes into a class (.java file)
* JVM compiles the file, a .class file is created
*
* The program starts in main()
* The return type void means there is no returned value
* Every statement must end in semicolon
*/
package com.minte9.basics.classes;
public class Classes {
public static void main( String[] args ) {
System.out.println("Hello World!"); // Hello World!
}
}
Blueprint
A class is a blueprint for an object.
/**
* A class is a blueprint for an object
*
* Instance variables (fields) is what an object knows
* Methods is what an object does
*/
package com.minte9.basics.classes;
public class Blueprint {
public static void main(String[] args) {
MyClass obj = new MyClass();
obj.setName("John");
System.out.println("Hello " + obj.name); // Hello John
}
}
class MyClass {
public String name;
public void setName(String name) {
this.name = name;
}
}
Last update: 204 days ago
