Graphics.getFontMetrics() has the following syntax.
public FontMetrics getFontMetrics()
In the following code shows how to use Graphics.getFontMetrics() method.
//from ww w .jav a 2 s . com import java.awt.Color; import java.awt.Font; import java.awt.FontMetrics; import java.awt.Graphics; import javax.swing.JFrame; import javax.swing.JPanel; public class Main extends JPanel { public void paint(Graphics g) { int fontSize = 20; g.setFont(new Font("TimesRoman", Font.PLAIN, fontSize)); FontMetrics fm = g.getFontMetrics(); String s = "www.java2s.com"; int stringWidth = fm.stringWidth(s); int w = 200; int h = 200; int x = (w - stringWidth) / 2; int baseline = fm.getMaxAscent() + (h - (fm.getAscent() + fm.getMaxDecent()))/2; int ascent = fm.getMaxAscent(); int descent = fm.getMaxDecent(); int fontHeight = fm.getMaxAscent() + fm.getMaxDecent(); g.setColor(Color.white); g.fillRect(x, baseline-ascent , stringWidth, fontHeight); g.setColor(Color.gray); g.drawLine(x, baseline, x+stringWidth, baseline); g.setColor(Color.red); g.drawLine(x, baseline+descent, x+stringWidth, baseline+descent); g.setColor(Color.blue); g.drawLine(x, baseline-ascent, x+stringWidth, baseline-ascent); g.setColor(Color.black); g.drawString(s, x, baseline); } public static void main(String[] args) { JFrame frame = new JFrame(); frame.add(new Main()); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); frame.setBounds(20,20, 500,500); frame.setVisible(true); } }