c3p0 配置问题。

Question

当我把 user 改成 usename 会报这个错误，觉得很奇怪（name="" ）名字不可以随便填吗？还有当我改变jdcbUrl的名字也会出现类似错误,如果名字如下图，就没有报错，可以执行，是c3p0规定了他们的名字吗？

Error creating bean with name 'dataSource' defined in class path resource [spring/spring-dao.xml]: Error setting property values; nested exception is org.springframework.beans.NotWritablePropertyException: Invalid property 'username' of bean class [com.mchange.v2.c3p0.ComboPooledDataSource]: Bean property 'username' is not writable or has an invalid setter method. Does the parameter type of the setter match the return type of the getter?