刚才去http://www.yeo.id.au/jmagick/ 搜索了一下。要在tomcat中使用JMagicK需要这三步：
1. Put Jmagick.jar in your WEBINF/lib dir
2. Put the following line in an initialization part of your webapp:
//Tell jmagick.magick.Magick to not use the system ClassLoader
System.setProperty("jmagick.systemclassloader","no");
3. make sure the Jmagick.dll and Imagemagick dlls are on the system
path
如果不做第二步，会一直报错。
