ERROR [localhost-startStop-1] - Context initialization failed

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'productService' defined in class path resource [applicationContext.xml]: Initialization of bean failed; nested exception is org.springframework.beans.ConversionNotSupportedException: Failed to convert property value of type 'cn.muke.ssh.service.ProductService' to required type 'cn.muke.ssh.dao.ProductDao' for property 'productDao'; nested exception is java.lang.IllegalStateException: Cannot convert value of type [cn.muke.ssh.service.ProductService] to required type [cn.muke.ssh.dao.ProductDao] for property 'productDao': no matching editors or conversion strategy found

 求大神回答这什么问题 万分感谢！