java - Focus not being set by method to grab focus -

learning code, building gui figure out how interacts. trying write method set focus on (component) @ points need in larger program - ie call focusgrabber(jtextfield1) , have set input focus on jtextfield1. in attempt best sscce, i've made simple main makes enough gui give 2 textfields should set focus on second.

package odin; import java.awt.component; import java.util.list; import javax.swing.jcomponent; import javax.swing.jframe; import javax.swing.jlabel; import javax.swing.jtextfield; /* */ class focusgrabber implements runnable {     private jcomponent component;     public focusgrabber(jcomponent component) {         this.component = component;     }     @override     public void run() {         component.grabfocus();     }      public static void main(string[] args){         //draw , show gui         jframe gui = new jframe();         gui.settitle("new provider interface");         gui.setdefaultcloseoperation(jframe.exit_on_close);         final jtextfield textid = new jtextfield("providerid ", 20);         final jtextfield textname = new jtextfield("provider name ", 20);          gui.add(textid);         gui.add(textname);         gui.pack();         gui.setvisible(true);         focusgrabber(textname);     }  } 

use requestfocusinwindow on grabfocus...

it helpful if called run method @ point

also, shouldn't more like

focusgrabber fg = new focusgrabber(textname); fg.run();