Superclass没有null构造函数,但没有给出参数

nil*_*lsi 31 spring facebook hibernate inject spring-social

我在我的应用程序中使用Spring Social:

<spring.framework.version>3.2.0.RELEASE</spring.framework.version>
<hibernate.version>4.1.9.Final</hibernate.version>
<commons-dbcp.version>1.4</commons-dbcp.version>
<org.springframework.social-version>1.1.0.BUILD-SNAPSHOT</org.springframework.social-version>
<org.springframework.social.facebook-version>1.1.0.BUILD-SNAPSHOT</org.springframework.social.facebook-version>
<org.springframework-version>3.2.1.RELEASE</org.springframework-version>
<org.springframework.security.crypto-version>3.1.3.RELEASE</org.springframework.security.crypto-version>
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当我申请

private final Facebook facebook;

@Inject
public SearchController(Facebook facebook) {
    this.facebook = facebook;
}
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到我的HomeController:

@Controller
public class HomeController {


    private final Facebook facebook;

    @Inject
    public HomeController(Facebook facebook) {
        this.facebook = facebook;
    }

    private static final Logger logger = LoggerFactory.getLogger(HomeController.class);

    /**
     * Simply selects the home view to render by returning its name.
     */
    @RequestMapping(value = "/", method = RequestMethod.GET)
    public String home(Model model) {
        return "home";
    }

}
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注射工作就像有意,我可以从中获取信息facebook.但是,当我将它应用到我的其他Cotrollers之类的时候

@Controller
@Transactional
@RequestMapping(value = "/search")
public class SearchController {

    private static final Logger logger = LoggerFactory.getLogger(SearchController.class);

    private final Facebook facebook;

    @Inject
    public SearchController(Facebook facebook) {
        this.facebook = facebook;
    }

    @PersistenceContext
    private EntityManager entityManager;

    ...
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我收到此错误:

mar 05, 2013 12:46:36 EM org.apache.catalina.core.StandardWrapperValve invoke
SEVERE: Servlet.service() for servlet [appServlet] in context with path [/project] threw exception [Request processing failed; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'searchController' defined in file [C:\Users\Nilsi\Downloads\springsource\vfabric-tc-server-developer-2.7.2.RELEASE\base-instance\wtpwebapps\course_info\WEB-INF\classes\com\courseinfo\project\controller\SearchController.class]: Initialization of bean failed; nested exception is org.springframework.aop.framework.AopConfigException: Could not generate CGLIB subclass of class [class com.courseinfo.project.controller.SearchController]: Common causes of this problem include using a final class or a non-visible class; nested exception is java.lang.IllegalArgumentException: Superclass has no null constructors but no arguments were given] with root cause
java.lang.IllegalArgumentException: Superclass has no null constructors but no arguments were given
    at org.springframework.cglib.proxy.Enhancer.emitConstructors(Enhancer.java:721)
    at org.springframework.cglib.proxy.Enhancer.generateClass(Enhancer.java:499)
    at org.springframework.cglib.transform.TransformingClassGenerator.generateClass(TransformingClassGenerator.java:33)
    at org.springframework.cglib.core.DefaultGeneratorStrategy.generate(DefaultGeneratorStrategy.java:25)
    at org.springframework.cglib.core.AbstractClassGenerator.create(AbstractClassGenerator.java:216)
    at org.springframework.cglib.proxy.Enhancer.createHelper(Enhancer.java:377)
    at org.springframework.cglib.proxy.Enhancer.create(Enhancer.java:285)
    at org.springframework.aop.framework.CglibAopProxy.getProxy(CglibAopProxy.java:205)
    at org.springframework.aop.framework.ProxyFactory.getProxy(ProxyFactory.java:111)
    at org.springframework.aop.framework.autoproxy.AbstractAutoProxyCreator.createProxy(AbstractAutoProxyCreator.java:477)
    at org.springframework.aop.framework.autoproxy.AbstractAutoProxyCreator.wrapIfNecessary(AbstractAutoProxyCreator.java:362)
    at org.springframework.aop.framework.autoproxy.AbstractAutoProxyCreator.postProcessAfterInitialization(AbstractAutoProxyCreator.java:322)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyBeanPostProcessorsAfterInitialization(AbstractAutowireCapableBeanFactory.java:412)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1492)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:524)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:461)
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:295)
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:223)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:292)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194)
    at org.springframework.context.support.AbstractApplicationContext.getBean(AbstractApplicationContext.java:1117)
    at org.springframework.web.method.HandlerMethod.createWithResolvedBean(HandlerMethod.java:202)
    at org.springframework.web.servlet.handler.AbstractHandlerMethodMapping.getHandlerInternal(AbstractHandlerMethodMapping.java:233)
    at org.springframework.web.servlet.handler.AbstractHandlerMethodMapping.getHandlerInternal(AbstractHandlerMethodMapping.java:55)
    at org.springframework.web.servlet.handler.AbstractHandlerMapping.getHandler(AbstractHandlerMapping.java:297)
    at org.springframework.web.servlet.DispatcherServlet.getHandler(DispatcherServlet.java:1091)
    at org.springframework.web.servlet.DispatcherServlet.getHandler(DispatcherServlet.java:1076)
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:896)
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:856)
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:920)
    at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:827)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:641)
    at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:801)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:168)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:99)
    at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:929)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:407)
    at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1002)
    at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:585)
    at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:312)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)
    at java.lang.Thread.run(Thread.java:722)
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我的猜测是我不能将注入@Transactional注入facebook的控制器?我google了一下,但无法找到任何解决方案.

Mak*_*das 60

CGlib有一个重要的限制:目标类必须提供默认构造函数.

如果使用基于属性的注入而不是基于构造函数的注入,问题就会消失.

  • 扩展这个答案:如果没有将`@Transactional`添加到控制器,这可以通过构造函数注入(这是首选)工作正常.一旦你添加了`@Transactional`,AOP就会启动并且必须创建一个代理.CGLib需要一个默认的构造函数.另一种解决方案是将Spring事务配置为使用AspectJ而不是代理.这需要更多的设置,但允许没有默认构造函数的类上的事务. (45认同)
  • 在Spring 4之前,基于CGLIB的代理类需要一个默认构造函数.这不是CGLIB库的限制,而是Spring本身.幸运的是,从春季开始,这不再是一个问题.基于CGLIB的代理类不再需要默认构造函数.请参阅此文章:http://blog.codeleak.pl/2014/07/spring-4-cglib-based-proxy-classes-with-no-default-ctor.html (8认同)
  • 这是一个非常好的评论!我认为它应该添加到答案中. (3认同)
  • 我发现了一种使用构造函数注入和`@Transactional`的方法.创建一个`SearchController`实现的接口,并改变`HomeController`的构造函数来取代这个接口的实例. (3认同)
  • 基本上使`HomeController`依赖于接口,而不是实现. (2认同)