import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import javax.swing.JComponent;
import javax.swing.JFrame;
public class Main {
public static void main(String[] args) {
new Main();
}
Main() {
JFrame frame = new JFrame();
frame.add(new MyComponent());
frame.setSize(300, 300);
frame.setVisible(true);
}
}
class MyComponent extends JComponent {
public void paint(Graphics g) {
Graphics2D g2d = (Graphics2D) g;
RenderingHints rhints = g2d.getRenderingHints();
boolean antialiasOn = rhints.containsValue(RenderingHints.VALUE_ANTIALIAS_ON);
g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
}
}