关于pdf文件的类库
1）http://www.javaeye.com/topic/509417
2）the flying saucer project ----- https://xhtmlrenderer.dev.java.net/
3) http://www.javaeye.com/topic/57126
4）http://www.javaeye.com/topic/315849
关于可变参数：
1）http://topic.csdn.net/t/20041124/09/3582660.html
