参考：
http://chenchaobox.blog.163.com/blog/static/6043759020127845945569/
https://blog.csdn.net/cl18652469346/article/details/53117023
Java-awt-获取g.drawString绘制文字的宽度和高度
原文：https://www.cnblogs.com/cappuccinom/p/9190600.html
