spring 超类没有空构造函数，但没有给出参数

Superclass has no null constructors but no arguments were given

提问by nilsi

Im using Spring Social in my application:

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>

When I apply

当我申请

private final Facebook facebook;

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

To my HomeController:

到我的家庭控制器：

@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";
    }

}

The injection works like intented and I can get information from facebook. However, when I apply it to one of my other Cotrollers like this one

注入的工作就像意图一样，我可以从facebook. 但是，当我将它应用到我的其他 Cotroller 之一时

@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;

    ...

I getting this error:

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.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)

My guess is that I can't inject facebook to a Controller with annotation @Transactional? I googled around but cant find any solution to this.

我的猜测是我无法将 facebook 注入带有注释 @Transactional 的控制器？我用谷歌搜索，但找不到任何解决方案。

回答by Maksym Demidas

CGlib has one important restriction: the target class must provide a default constructor.

CGlib 有一个重要限制：目标类必须提供默认构造函数。

If you use property-based injection instead of constructor-based injection, the problem will go away.

如果您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。

回答by Smart Coder

I just created an empty default constructor to deal with this.

我刚刚创建了一个空的默认构造函数来处理这个问题。

回答by Navigatron

If you are using Lombokin your code, then you can just add the following annotation to get rid of this error:

如果您在代码中使用Lombok，则只需添加以下注释即可消除此错误：

@NoArgsConstructor
public class SearchController {