说明：  util实现Java图片水印添加功能，有添加图片水印和文字水印，可以设置水印位置，透明度、设置对线段锯齿状边缘处理、水印图片的路径，水印一般格式是gif，png,这种图片可以设置透明度、水印旋转等，可以参考代码加以改进做成小工具。
(Util realize the Java image watermark to add functionality, add watermark images and text watermark, watermark can set the transparency, set position, on the line of jagged edge processing, watermark image path, image formats are GIF, PNG, this picture can set the transparency of watermark, rotation, can refer to the code can be improved to make gadgets.)