错误笔记

1、

Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type

‘studentManager.dao.ZhuanYeDao’ available: expected at least 1 bean which qualifies as autowire candidate.

Dependency annotations: {@javax.annotation.Resource(shareable=true, lookup=, name=, description=,

authenticationType=CONTAINER, type=class java.lang.Object, mappedName=)}

原因：在dao里未配置@respository

2、

org.hibernate.HibernateException: Could not obtain transaction-synchronized Session for current thread

原因：忘记写上<tx:annotation-driven transaction-manager=“txManager”/>

此句的意思为声明事物处理为注释类型，如果不写上此句，默认为以下的事物处理为xml配置

<bean id="txManager"
     class="org.springframework.orm.hibernate4.HibernateTransactionManager">
    <property name="sessionFactory" ref="sessionFactory"/>
</bean>

org.hibernate.HibernateException: Could not obtain transaction-synchronized Session for current thread

原因：忘记写上<tx:annotation-driven transaction-manager=“txManager”/>

此句的意思为声明事物处理为注释类型，如果不写上此句，默认为以下的事物处理为xml配置

<bean id="txManager" class="org.springframework.orm.hibernate4.HibernateTransactionManager">
    <property name="sessionFactory" ref="sessionFactory"/>
</bean>

3、

org.springframework.dao.InvalidDataAccessApiUsageException: deleted object would be re-saved by cascade

(remove deleted object from associations): [studentmanagement.po.Student#1]; nested exception is

org.hibernate.ObjectDeletedException: deleted object would be re-saved by cascade (remove deleted object from

associations): [studentmanagement.po.Student#1]

原因：级联操作删除时，需要级联删除但是没有设置级联删除 或者是级联操作的参数权限大小有问题，例如删除

student（class cascade=“none”）时class（student cascade=“delete”）指的是student的操作不对class产生影响，删除

class的同时student

级联配置的是本对象的改变对相关连对象产生什么样影响

none：在保存，删除或修改当前对象时，不对其附属对象（关联对象）进行级联操作。它是默认值。

save-update：在保存，更新当前对象时，级联保存，更新附属对象(临时对象，游离对象)。

delete：在删除当前对象时，级联删除附属对象。

all：所有情况下均进行级联操作，即包含save-update和delete操作。

delete-orphan：删除和当前对象解除关系的附属对象。

4、

There is no Action mapped for namespace [/] and action name [ZhuanYeAction_addZhuanYeUI] associated with

context path [].

原因：struts2未放在src的根下