Why the info from introspection. GetPropertyDescriptors () to obtain properties will have a class this term?

By means of an introspection for ordinary javabean properties, why many a class, I thought this class animal sign are inherited from the Object, but view the Object class source code Only this way the public final native Class getClass (); , and this method is final, and do not make me the javabean object inheritance. But why would the class this term?

This is java bean:

public class ITest {
    private String appid;
    private String mch_id;
    private String device_info;
    private String Body;
    private String nonce_str;
    public String getAppid() {
        return appid;
    }
    public void setAppid(String appid) {
        this.appid = appid;
    }
    public String getMch_id() {
        return mch_id;
    }
    public void setMch_id(String mch_id) {
        this.mch_id = mch_id;
    }
    public String getDevice_info() {
        return device_info;
    }
    public void setDevice_info(String device_info) {
        this.device_info = device_info;
    }
    public String getBody() {
        return Body;
    }
    public void setBody(String body) {
        Body = body;
    }
    public String getNonce_str() {
        return nonce_str;
    }
    public void setNonce_str(String nonce_str) {
        this.nonce_str = nonce_str;
    }
}

This is my method:

public static Map<String, Object> beanToMap(Object bean, boolean isempty)
        throws IntrospectionException, IllegalAccessException, IllegalArgumentException {
    Class<? extends Object> type = bean.getClass();
    Map<String, Object> params = new TreeMap<String, Object>();
    BeanInfo info = Introspector.getBeanInfo(type);
    PropertyDescriptor[] descriptors = info.getPropertyDescriptors();
    for (int i = 0; i < descriptors.length; i++) {
        PropertyDescriptor descriptor = descriptors[i];
        String propertyName = descriptor.getName();
        Method readMethod = descriptor.getReadMethod();
        try {
            Object result = readMethod.invoke(bean, new Object[0]);
            System.out.println(propertyName + "=" + result);
            if (result != null) {
                params.put(propertyName, result);
            } else {
                if (isempty)
                    params.put(propertyName, "");
            }
        } catch (InvocationTargetException e) {
            log.error("readMethod invoke" + bean + ":" + e.getMessage());
        }
    }
    return params;
}

Why did the results more class attribute this item

appid=wxd930ea5d5a258f4f
body=test
class=class com.haothink123.entity.ITest
device_info=1000
mch_id=10000100
nonce_str=ibuaiVcKdpRxkhJA