现象： 执行demo，比如helloexample ，点击“run as mule application”，弹出框“Could not find the main class.Program will exit”
控制台出现：
java.lang.NoClassDefFoundError: org/mule/tooling/server/application/ApplicationDeployer
Exception in thread "main"
解决方法： 是因为jdk 有问题，在mule官网上要求
Before installing Mule Studio, ensure that the host machine has one of the following Java Development Kit versions installed on it:
- Standard Edition 1.6.0_26 (also known as JDK SE 6 Update 26) or more recent
- Enterprise Edition 1.6u3 (JDK EE 6 Update 3) or more recent
- Any version (SE or EE) of JDK 7
在java build path--》libraries 选择jre system library 为jdk1.7就可以。