Proxy Exception while injecting spring bean into J

2019-06-04 00:49发布

问题:

I'm trying to inject spring bean into JSF bean, I'm using Spring 3.1 and JSF 2 (Mojarra 2.1.7)

Without a lot of talking my configuration and code and exception listed in the following:

StudentService.java:

@Scope(proxyMode=ScopedProxyMode.TARGET_CLASS)
public class StudentsService extends AbstractMaqraaService {

    @Override
    public Set<Class<?>> getTypes() {
        // TODO Auto-generated method stub
        return null;
    }

    public Student registerStudent(Student student) {
        return this.store(student);
    }

}

StudentRegistrationMBean.java:

@ManagedBean(name="studentRegistrationMBean") 
@SessionScoped
public class StudentRegistrationMBean extends AbstractMBean {

    private Student student;
    @ManagedProperty (value="#{studentsService}")
    private StudentsService studentsService;

    public StudentRegistrationMBean() {
        this.student = new Student();
    }

    /*Setters and getters omitted here only*/

    public String register() {

        studentsService.registerStudent(student);
        return "manageStudents";
    }
}

Spring bean in module context xml file:

<bean id="abstractMaqraaService" class="org.tts.maqraa.service.AbstractMaqraaService" abstract="true"/>

<bean id="studentsService" class="org.tts.maqraa.service.StudentsService" lazy-init="default" parent="abstractMaqraaService"/>

faces-config.xml:

...
<application>
        <el-resolver>org.springframework.web.jsf.el.SpringBeanFacesELResolver</el-resolver>
</application>
...

Eception:

TRACE [http-bio-8080-exec-3] (SpringBeanELResolver.java:53) - Successfully resolved variable 'studentsService' in Spring BeanFactory
DEBUG [http-bio-8080-exec-3] (AbstractBeanFactory.java:245) - Returning cached instance of singleton bean 'studentsService'
نوار 13, 2012 11:10:45 ص com.sun.faces.application.view.FaceletViewHandlingStrategy handleRenderException
SEVERE: Error Rendering View[/teacher/registerNewStudent.xhtml]
com.sun.faces.mgbean.ManagedBeanCreationException: Unable to set property studentsService for managed bean studentRegistrationMBean
    at com.sun.faces.mgbean.ManagedBeanBuilder$BakedBeanProperty.set(ManagedBeanBuilder.java:615)
    at com.sun.faces.mgbean.ManagedBeanBuilder.buildBean(ManagedBeanBuilder.java:133)
    ...
    at java.lang.Thread.run(Unknown Source)
Caused by: javax.el.ELException: Cannot convert org.tts.maqraa.service.StudentsService@8f65bc0 of type class $Proxy10 to class org.tts.maqraa.service.StudentsService
    at org.apache.el.lang.ELSupport.coerceToType(ELSupport.java:420)
    at org.apache.el.ExpressionFactoryImpl.coerceToType(ExpressionFactoryImpl.java:47)
    at com.sun.faces.el.ELUtils.coerce(ELUtils.java:536)
    at com.sun.faces.mgbean.BeanBuilder$Expression.evaluate(BeanBuilder.java:592)
    at com.sun.faces.mgbean.ManagedBeanBuilder$BakedBeanProperty.set(ManagedBeanBuilder.java:606)
    ... 47 more

ERROR [http-bio-8080-exec-3] (MaqraaExceptionHandler.java:83) - Exception
javax.el.ELException: Cannot convert org.tts.maqraa.service.StudentsService@8f65bc0 of type class $Proxy10 to class org.tts.maqraa.service.StudentsService
    at org.apache.el.lang.ELSupport.coerceToType(ELSupport.java:420)
    ...
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
    at java.lang.Thread.run(Unknown Source)

I made a lot of search in Google and found a lot of questions here had issues like mine but nothing helped me, I hope I'll find my solution for my special case !!

回答1:

use <aop:aspectj-autoproxy proxy-target-class="true"/> to enforce use of JDK proxy rather than CGLIB



回答2:

if you inject your Spring service like this don't forget to create the setter for your Service:

@ManagedProperty (value="#{studentsService}")
private StudentsService studentsService;

public void setStudentsService (StudentsService studentsService)
{
    this.studentsService = studentsService;
}

With the @Autowired annotation there was no need to do this.

Take a look at this answer It's about not using an interface for using your proxy.