I want to know how to center the JFrame title.I referred following link How to center align the title in a JFrame?
but I need to center title without putting spacing.
Consider leaving the title left-justified...but...this will get you near the center. For resizable frames, you need to rewrite the title on resize.
JFrame t = new JFrame();
t.setSize(600,300);
t.setFont(new Font("System", Font.PLAIN, 14));
Font f = t.getFont();
FontMetrics fm = t.getFontMetrics(f);
int x = fm.stringWidth("Hello Center");
int y = fm.stringWidth(" ");
int z = t.getWidth()/2 - (x/2);
int w = z/y;
String pad ="";
//for (int i=0; i!=w; i++) pad +=" ";
pad = String.format("%"+w+"s", pad);
t.setTitle(pad+"Hello Center");