使用Swing绘制Java网格

该代码有效。

只需删除25

import java.awt.*; import javax.swing.*; public class Grid extends Jframe { public Grid()    {        setSize( 500, 500 ); setVisible( true );    } public void paint( Graphics g )     {   for ( int x = 30; x <= 300; x += 30 ) for ( int y = 30; y <= 300; y += 30 )  g.drawRect( x, y, 30, 30 ); }  public static void main( String args[] )  {     Grid application = new Grid(); application.setDefaultCloseOperation( Jframe.EXIT_ON_CLOSE );   }  }