Javassistを使ってJavaのfinalクラスの拡張は・・・

できなかった。
Stringクラスの拡張をしたかった。

ExtendSample.java

package javassist.test;

import javassist.ClassPool;
import javassist.CtClass;

public class ExtendSample {
	public static void main(String[] args) throws Exception{
		ClassPool pool = ClassPool.getDefault();
		CtClass cc = pool.makeClass("dynamic.clazz.Sample");
		cc.setSuperclass(pool.get("java.lang.String"));
		Class<?> clazz = cc.toClass();
		Object obj = clazz.newInstance();
	}
}

Exception in thread "main" javassist.CannotCompileException: by java.lang.VerifyError: Cannot inherit from final class
	at javassist.ClassPool.toClass(ClassPool.java:1099)
	at javassist.ClassPool.toClass(ClassPool.java:1042)
	at javassist.ClassPool.toClass(ClassPool.java:1000)
	at javassist.CtClass.toClass(CtClass.java:1224)
	at javassist.test.ExtendSample.main(ExtendSample.java:11)
Caused by: java.lang.VerifyError: Cannot inherit from final class
	at java.lang.ClassLoader.defineClass1(Native Method)
	at java.lang.ClassLoader.defineClassCond(Unknown Source)
	at java.lang.ClassLoader.defineClass(Unknown Source)
	at java.lang.ClassLoader.defineClass(Unknown Source)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
	at java.lang.reflect.Method.invoke(Unknown Source)
	at javassist.ClassPool.toClass2(ClassPool.java:1112)
	at javassist.ClassPool.toClass(ClassPool.java:1093)
	... 4 more