spring配置问题:'target' is required
为什么报这个错呢?
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'userDAOProxy ' defined in ServletContext resource [/WEB-INF/applicationContext-transa.xml]: Initialization of bean failed; nested exception is java.lang.IllegalArgumentException: 'target ' is required

java.lang.IllegalArgumentException: 'target ' is required

我的配置文件内容如下

<bean id="userDAOProxy" class="org.springframework.transaction.interceptor.TransactionProxyFactoryBean" >

<property name="transactionManager" >
<ref bean="myTransactionManager"/ >
</property >
<property name="transactionAttributes" >
<props >
<prop key="Add*" >PROPAGATION_REQUIRED </prop >
<prop key="Modi*" >PROPAGATION_REQUIRED </prop >
<prop key="Delete*" >PROPAGATION_REQUIRED </prop >
<prop key="Select*" >PROPAGATION_REQUIRED </prop >
</props >
</property >
</bean >

<bean name="/login" class="com.icss.scte.ssh.action.LoginAction" singleton="false" >
<property name="sel" >
<ref bean="userDAOProxy"/ >
</property >
<property name="add" >
<ref bean="userDAOProxy"/ >
</property >
</bean >

<bean id="selectImpl" parent="userDAOProxy" >
<property name="target" >
<ref bean="selectImpl"/ >
</property >
</bean >

<bean name="selectImpl" class="com.icss.scte.ssh.daoimpl.SelectImpl" >
<property name="sessionFactory" >
<ref bean="sessionFactory"/ >
</property >
</bean >

LoginAction中为:

private Select sel;
private Add add;


public Select getSel() {
return sel;
}

public void setSel(Select sel) {
this.sel = sel;
}

public Add getAdd() {
return add;
}

public void setAdd(Add add) {
this.add = add;
}

[解决办法]
<bean id="userDAOProxy" class="org.springframework.transaction.interceptor.TransactionProxyFactoryBean" >

<property name="transactionManager" >
<ref bean="myTransactionManager"/ >
</property >
<property name="target">
<ref local="selectImpl" />
</property>
<property name="transactionAttributes" >
<props >
<prop key="Add*" >PROPAGATION_REQUIRED </prop >
<prop key="Modi*" >PROPAGATION_REQUIRED </prop >
<prop key="Delete*" >PROPAGATION_REQUIRED </prop >
<prop key="Select*" >PROPAGATION_REQUIRED </prop >

</props >
</property >
</bean >

<bean name="/login" class="com.icss.scte.ssh.action.LoginAction" singleton="false" >
<property name="sel" >
<ref bean="userDAOProxy"/ >
</property >
<property name="add" >
<ref bean="userDAOProxy"/ >
</property >
</bean >

<bean id="selectImpl" parent="userDAOProxy" >
<property name="target" >
<ref bean="selectImpl"/ >
</property >
</bean >

<bean name="selectImpl" class="com.icss.scte.ssh.daoimpl.SelectImpl" >
<property name="sessionFactory" >
<ref bean="sessionFactory"/ >
</property >
</bean >