stack trace

java.lang.RuntimeException: by java.lang.NoClassDefFoundError: javassist/util/proxy/ProxyObject
	at javassist.util.proxy.ProxyFactory.createClass3(ProxyFactory.java:515)
	at javassist.util.proxy.ProxyFactory.createClass2(ProxyFactory.java:492)
	at javassist.util.proxy.ProxyFactory.createClass1(ProxyFactory.java:428)
	at javassist.util.proxy.ProxyFactory.createClass(ProxyFactory.java:400)
	at mit.proxy.ProxyCreator.create(ProxyCreator.java:112)
	at mit.proxy.ProxyCreator.main(ProxyCreator.java:77)
Caused by: javassist.CannotCompileException: by java.lang.NoClassDefFoundError: javassist/util/proxy/ProxyObject
	at javassist.util.proxy.FactoryHelper.toClass(FactoryHelper.java:170)
	at javassist.util.proxy.ProxyFactory.createClass3(ProxyFactory.java:507)
	... 5 more
Caused by: java.lang.NoClassDefFoundError: javassist/util/proxy/ProxyObject
	at java.lang.ClassLoader.defineClass1(Native Method)
	at java.lang.ClassLoader.defineClass(ClassLoader.java:760)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:483)
	at javassist.util.proxy.FactoryHelper.toClass2(FactoryHelper.java:182)
	at javassist.util.proxy.FactoryHelper.toClass(FactoryHelper.java:164)
	... 6 more
Caused by: java.lang.ClassNotFoundException: javassist.util.proxy.ProxyObject
	at java.net.URLClassLoader$1.run(URLClassLoader.java:372)
	at java.net.URLClassLoader$1.run(URLClassLoader.java:361)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.net.URLClassLoader.findClass(URLClassLoader.java:360)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
	... 14 more