在java面板中绘制矩形，三角形，圆形，箭头，直线等图形，并实现拖动，变化大小，可以保存当前文件，并打开文件进行编辑-Draw a rectangle, triangle, circle, arrow, straight line, etc. in the Java panel, and realize the drag, change the size, you can save the current file, and open the file to edit