Java.lang.ClassCastException:com.sun.proxy. $Proxy cannot is cast to Sm.dao.UserDao

Issues that occur after you add a thing management in spring

Source

New Classpathxmlapplicationcontext ("Applicationcontext.xml"= (Userdao) applicationcontext.getbean ("UserDao" );

Error reasons for spring AOP using two proxy methods, one is a regular JDK, one is cglib, my Userdao an interface Iuserdao, when the proxy object implements at least one interface, the default use JDK dynamically create proxy object, The Cglib method is used when the proxy object does not implement any interfaces. Specific introduction of the article

Workaround:

Because JDK-based proxies are interface-oriented, we modify the code ourselves as follows

   New Classpathxmlapplicationcontext ("Applicationcontext.xml");     = (Iuserdao) applicationcontext.getbean ("Userdao");

Attach Applicationcontext.xml Configuration

<?XML version= "1.0" encoding= "UTF-8"?><Beansxmlns= "Http://www.springframework.org/schema/beans"Xmlns:xsi= "Http://www.w3.org/2001/XMLSchema-instance"Xmlns:jdbc= "Http://www.springframework.org/schema/jdbc"Xmlns:tx= "Http://www.springframework.org/schema/tx"xsi:schemalocation= "Http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd HTTP://WWW.SPRINGFRAMEWORK.ORG/SCHEMA/JDBC http://www.springframework.org/schema/jdbc/spring-jdbc.xsd/HTTP Www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd ">    <BeanID= "Datasoure"class= "Org.apache.commons.dbcp.BasicDataSource">        < Propertyname= "Driverclassname"value= "Com.mysql.jdbc.Driver"></ Property>        < Propertyname= "url"value= "Jdbc:mysql://localhost:3306/sm"></ Property>        < Propertyname= "username"value= "root"></ Property>        < Propertyname= "Password"value= "Genji"></ Property>    </Bean>    <BeanID= "Sessionfactory"class= "Org.springframework.orm.hibernate4.LocalSessionFactoryBean">        < Propertyname= "DataSource">            <refBean= "Datasoure"></ref>        </ Property>        < Propertyname= "Hibernateproperties">            <Props>                <propKey= "Hibernate.dialect">Org.hibernate.dialect.MySQL5Dialect</prop>                <propKey= "Hibernate.current_session_context_class">Org.springframework.orm.hibernate4.SpringSessionContext</prop>            </Props>        </ Property>        < Propertyname= "Mappingresources">            <List>                <value>Sm/po/studentinfo.hbm.xml</value>                <value>Sm/po/user.hbm.xml</value>            </List>        </ Property>    </Bean>    <BeanID= "Userdao"class= "Sm.dao.UserDao">        < Propertyname= "Sessionfactory">            <refBean= "Sessionfactory"></ref>        </ Property>    </Bean>    <BeanID= "Sinfodao"class= "Sm.dao.SinfoDao">        < Propertyname= "Sessionfactory">            <refBean= "Sessionfactory"></ref>        </ Property>    </Bean>
This is where the transaction agent is implemented.
    <BeanID= "Txmanager"class= "Org.springframework.orm.hibernate4.HibernateTransactionManager">        < Propertyname= "Sessionfactory"ref= "Sessionfactory" />    </Bean>    <Tx:annotation-driven/>    <Tx:adviceID= "Txadvice"Transaction-manager= "Txmanager">        <tx:attributes>            <Tx:methodname= "Add"read-only= "true"Propagation= "REQUIRED" />            <Tx:methodname= "read"Propagation= "REQUIRED" />            <Tx:methodname= "Del"Propagation= "REQUIRED" />            <Tx:methodname= "mod"Propagation= "REQUIRED" />            <Tx:methodname= "Sameid"Propagation= "REQUIRED" />            <Tx:methodname= "Finduser"Propagation= "REQUIRED"/>            <Tx:methodname= "AddUser"Propagation= "REQUIRED"></Tx:method>        </tx:attributes>    </Tx:advice></Beans>

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http://cheneyjuu.blog.163.com/blog/static/41917640201051042941159/

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Java.lang.ClassCastException:com.sun.proxy. $Proxy cannot is cast to Sm.dao.UserDao