java - The method JFrame is undefined for the type HelloWorld -

i don't know why error on hello world java project:

the method jframe undefined type helloworld".

i started, can please explain me error , solution?

package helloworld;  import javax.swing.jframe;  public class helloworld  { public static helloworld helloworld; public final int width = 800, height = 800;  public helloworld() {      jframe jframe = jframe();     jframe.setsize(width, height);     jframe.setvisible(true);  } public static void main(string[] args) {     helloworld = new helloworld(); } } 

every object must instantiated new keyword in java. jframe jframe = new jframe("it's not hello world program");