import java.io.File;
import java.awt.Font;
import java.awt.GraphicsEnvironment;

public class myFontCheck {
  public static void main(String[] args) {
    Font[] fonts = GraphicsEnvironment.getLocalGraphicsEnvironment().getAllFonts();
    for (int i = 0; i < fonts.length; i++) {
      final Font font = fonts[i];
      final String name = font.getFontName();

      if (font.canDisplay('a') &&
        font.canDisplay('z') &&
        font.canDisplay('A') &&
        font.canDisplay('Z') &&
        font.canDisplay('0') &&
        font.canDisplay('1')) {
        //System.out.println(" OK.");
      } else {
        File file = new File("c:\Windows\Fonts\" + name + ".ttf");
        if(file.exists()) {
          System.out.println("Bad Font: " + name);
          file.delete();
        }
      }
    }
  }
}

if (font.canDisplay('a') &&
    font.canDisplay('z') &&
    font.canDisplay('A') &&
    font.canDisplay('Z') &&
    font.canDisplay('0') &&
    font.canDisplay('1')) {
    //System.out.println(" OK.");
  } else {
    System.out.println("Bad Font: " + name);
    File file = new File("c:\Windows\Fonts\" + name + ".ttf");
    file.delete();
  }

} else {
    System.out.println("Bad Font: " + name);
    String fn = "c:\Windows\Fonts\" + name + ".ttf";
    System.out.println("Trying to delete: " + fn);
    File file = new File(fn);
    file.delete();
  }