Object类共12个方法
2个public
boolean equals(Object obj) : this == obj
String toString(): getClass().getName() + “@” +Integer.toHexString(hascode())
1个public native
int hashCode()
2个public final
wait()
wait(long timeout,int nanos)
4个public final native
Class<?> getClass()
notify()
notifyAll()
wait(long timeout)
1个protected
finalize()
1个protected native
clone()
1个private static native
registernatives()
用来注册5个本地方法