为什么用BeanUtils就报错啊，求指导啊 - 黑马程序员技术交流社区

package zhangTech;
import java.beans.IntrospectionException;
import java.beans.PropertyDescriptor;
import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import org.apache.commons.beanutils.BeanUtils;
/*
* 定义一个标准的JavaBean，名叫Person，包含属性name、age。使用反射的方式创
建一个实例、调用构造函数初始化name、age，使用反射方式调用setName方法对名称进
行设置，不使用setAge方法直接使用反射方式对age赋值。
*/
class Person
{
public String name;
private int age;
public Person(String name, int age) {
this.name = name;
this.age = age;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
}
public class BeanDemo {
public static void main(String[] args) {
// TODO Auto-generated method stub
Class<Person> cls=Person.class;//获取字节码
String propertyName="name";
String name="yu";
String propertyAge="age";
int age=22;
Person p;
try{
Constructor<Person> con=cls.getConstructor(String.class,int.class);
p=con.newInstance("zhang",20);
//调用方法设置年龄和姓名属性值
mSetName( p, propertyName, name);
mSetAge(p ,propertyAge,age );
System.out.println(p.getName()+"--"+p.getAge());
BeanUtils.setProperty(p, propertyName, name);//这里一用就报错啊，为啥？
System.out.println(BeanUtils.getProperty(p, propertyName));//这列也是报错，求指导
}catch(Exception e){
e.printStackTrace();
}
}
private static void mSetName(Person p ,String propertyName, String name
) throws IntrospectionException, IllegalAccessException,
InvocationTargetException {
PropertyDescriptor pd=new PropertyDescriptor(propertyName, p.getClass());
Method methodSetName=pd.getWriteMethod();
methodSetName.invoke(p, name);
}
private static void mSetAge(Person p,String propertyAge,int age)
throws IntrospectionException, IllegalAccessException,
InvocationTargetException {
PropertyDescriptor pd=new PropertyDescriptor(propertyAge, p.getClass());
Method methodSetAge=pd.getWriteMethod();
methodSetAge.invoke(p, age);
}
}

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yu--22
java.lang.reflect.InvocationTargetException: Cannot set name
at org.apache.commons.beanutils.BeanUtilsBean.setProperty(BeanUtilsBean.java:1017)
at org.apache.commons.beanutils.BeanUtils.setProperty(BeanUtils.java:456)
at zhangTech.BeanDemo.main(BeanDemo.java:61)
Caused by: java.lang.NoSuchMethodException: Property 'name' has no setter method in class 'class zhangTech.Person'
at org.apache.commons.beanutils.PropertyUtilsBean.setSimpleProperty(PropertyUtilsBean.java:2128)
at org.apache.commons.beanutils.PropertyUtilsBean.setNestedProperty(PropertyUtilsBean.java:1948)
at org.apache.commons.beanutils.PropertyUtilsBean.setProperty(PropertyUtilsBean.java:2054)
at org.apache.commons.beanutils.BeanUtilsBean.setProperty(BeanUtilsBean.java:1015)
... 2 more

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