import java.util.*;
import java.awt.*;
import javax.swing.*;
public class Center{
  Dimension screenSize,frameSize;
  JFrame frame;
  public Center(JFrame frame){
    this.frame=frame;
    screenSize=Toolkit.getDefaultToolkit().getScreenSize();
    frameSize=frame.getSize();
  }
  public void center(){
    if(frameSize.height > screenSize.height){
      frameSize.height=screenSize.height;
    }
    if(frameSize.width >screenSize.width){
      frameSize.width=screenSize.width;
    }
    frame.setLocation((screenSize.width - frameSize.width)/2,
           (screenSize.height - frameSize.height)/2);
  }
}