DefaultAdvisorAutoProxyCreator代理

Question

DefaultAdvisorAutoProxyCreator代理应该是动态代理，既然是动态代理:代理类就需要接口，那么为什么下面的例子没有接口的类也能够被代理：
package chapter4.onlyfun.caterpillar.RegexpMatchDemo;public class HelloSpeaker2 { public void helloMaster(String name) {
System.out.println("Hello,"+name+" newbie!");
} public void hello1Newbie(String name) {
System.out.println("Hello,"+name+" master!");

}}package chapter4.onlyfun.caterpillar.RegexpMatchDemo;import java.lang.reflect.Method;
import java.util.logging.Level;
import java.util.logging.Logger;
import org.springframework.aop.MethodBeforeAdvice;public class LogBeforeAdvice 
        implements MethodBeforeAdvice { 
    private Logger logger = 
            Logger.getLogger(this.getClass().getName()); 
    
    public void before(Method method, Object[] args, 
                     Object target) throws Throwable { 
        logger.log(Level.INFO, 
                "liuyi method starts..." + method); 
   } 
}package chapter4.onlyfun.caterpillar.RegexpMatchDemo;import org.springframework.context.support.FileSystemXmlApplicationContext;import chapter3.onlyfun.caterpillar.AutoWireDemo.SpringDemo;public class SpringAOPDemo {
public static void main(String[] args) {

FileSystemXmlApplicationContext context = new FileSystemXmlApplicationContext(
new SpringAOPDemo().getAbsolutePath() + "/beans-config_DefalutAdvisorAutoProxyCreator.xml");

                  HelloSpeaker2 helloProxy=(HelloSpeaker2)context.getBean("helloSpeaker2");

helloProxy.hello1Newbie("Justin");
helloProxy.helloMaster("caterpillar");
}

private String getAbsolutePath() {
return this.getClass().getResource("").getPath().toString();
}
}<?xml version="1.0" encoding="UTF-8"?> 
<beans xmlns="http://www.springframework.org/schema/beans"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://www.springframework.org/schema/beans 
  http://www.springframework.org/schema/beans/spring-beans-2.0.xsd"> <bean id="logBeforeAdvice" class="chapter4.onlyfun.caterpillar.RegexpMatchDemo.LogBeforeAdvice"></bean>

<bean id="regExpAdvice" class="org.springframework.aop.support.RegexpMethodPointcutAdvisor">
<property name="pattern">
<value>.*Newbie</value>
</property>
<property name="advice" ref="logBeforeAdvice"></property>
</bean>
<bean id="helloSpeaker2" class="chapter4.onlyfun.caterpillar.RegexpMatchDemo.HelloSpeaker2"></bean>

<bean id="autoProxyCreator" class="org.springframework.aop.framework.autoproxy.DefaultAdvisorAutoProxyCreator">
</bean>
</beans>