Jsp Java EE错误：javax.enterprise.inject.UnsatifiedResolutionException:Api类型

我正在构建一个基于MVC架构的简单webapp。我有一个带有HTML表单的小JSP页面。表单数据被转发到servlet，然后servlet委托给控制器类

在表单上单击submit时，我得到一个HTTP状态500-由“UnsatifiedResolutionException”引起的错误。容器似乎找不到控制器

Context.xml

文件用作我的数据源。我正在使用ApacheTomee webprofile 1.7.4

错误：

type Exception report

message Error instantiating servlet class a1.DispatcherServlet

description The server encountered an internal error that prevented it from fulfilling this request.

exception

javax.servlet.ServletException: Error instantiating servlet class a1.DispatcherServlet
    org.apache.tomee.catalina.OpenEJBValve.invoke(OpenEJBValve.java:44)
    org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
    org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:956)
    org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:436)
    org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1078)
    org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:625)
    org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:318)
    java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
    java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
    org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
    java.lang.Thread.run(Thread.java:745)
root cause

javax.enterprise.inject.UnsatisfiedResolutionException: Api type [a1.Controller] is not found with the qualifiers 
Qualifiers: [@javax.inject.Named(value=customerController)]
for injection into Field Injection Point, field name :  customerController, Bean Owner : [DispatcherServlet, Name:null, WebBeans Type:DEPENDENT, API Types:[java.io.Serializable,javax.servlet.GenericServlet,java.lang.Object,a1.DispatcherServlet,javax.servlet.Servlet,javax.servlet.http.HttpServlet,javax.servlet.ServletConfig], Qualifiers:[javax.enterprise.inject.Any,javax.enterprise.inject.Default]]
    org.apache.webbeans.util.InjectionExceptionUtil.throwUnsatisfiedResolutionException(InjectionExceptionUtil.java:60)
    org.apache.webbeans.container.InjectionResolver.getInjectionPointBean(InjectionResolver.java:250)
    org.apache.webbeans.inject.AbstractInjectable.inject(AbstractInjectable.java:76)
    org.apache.webbeans.inject.InjectableField.doInjection(InjectableField.java:65)
    org.apache.webbeans.portable.InjectionTargetImpl.injectFields(InjectionTargetImpl.java:208)
    org.apache.webbeans.portable.InjectionTargetImpl.inject(InjectionTargetImpl.java:194)
    org.apache.webbeans.portable.InjectionTargetImpl.inject(InjectionTargetImpl.java:184)
    org.apache.webbeans.component.AbstractOwbBean.create(AbstractOwbBean.java:125)
    org.apache.openejb.core.WebContext.newInstance(WebContext.java:138)
    org.apache.tomee.catalina.JavaeeInstanceManager.newInstance(JavaeeInstanceManager.java:46)
    org.apache.tomee.catalina.JavaeeInstanceManager.newInstance(JavaeeInstanceManager.java:66)
    org.apache.tomee.catalina.JavaeeInstanceManager.newInstance(JavaeeInstanceManager.java:61)
    org.apache.tomee.catalina.OpenEJBValve.invoke(OpenEJBValve.java:44)
    org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
    org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:956)
    org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:436)
    org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1078)
    org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:625)
    org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:318)
    java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
    java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
    org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
    java.lang.Thread.run(Thread.java:745)

DispatcherServlet.java：

package a1;

/* Imports */

public class DispatcherServlet extends HttpServlet {
    private static final long serialVersionUID = 1L;

    @Inject
    @Named("customerController")
    private Controller customerController;

    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        try {
            String methodName = "addCustomer";

            Method method = customerController.getClass().getDeclaredMethod(methodName, HttpServletRequest.class);
            method.setAccessible(true);
            method.invoke(customerController, req);

            req.getRequestDispatcher("/success.jsp").forward(req, resp);
        } catch (SecurityException | IllegalArgumentException | NoSuchMethodException | IllegalAccessException | InvocationTargetException e) {
            throw new RuntimeException(e);
        }
    }
}

CustomerController.java：

package a1;

/* Imports */

@Named("customerController")
public class CustomerController implements Controller {

    @EJB
    private CustomerService customerServiceImpl;

    private void addCustomer(HttpServletRequest req) {
        long cn1 = Long.parseLong(req.getParameter("form_cust_no"));
        String n = req.getParameter("form_name");
        String s = req.getParameter("form_surname");

        try {
            SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMdd");
            String formDate = req.getParameter("form_dob");
            java.util.Date dateUtil = sdf.parse(formDate);
            java.sql.Date dateSql = new java.sql.Date(dateUtil.getTime());
            Customer customer = new Customer(cn1, n, s, dateSql);

            customerServiceImpl.addCustomer(customer);
        } catch (ParseException e) {
            throw new RuntimeException(e);
        }
    }
}

Web.xml：

<?xml version="1.0" encoding="ISO-8859-1"?>

<web-app xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
                      http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"
    version="3.0" metadata-complete="true">

    <servlet>
        <servlet-name>dispatcher</servlet-name>
        <servlet-class>a1.DispatcherServlet</servlet-class>
    </servlet>
    <servlet-mapping>
        <servlet-name>dispatcher</servlet-name>
        <url-pattern>/dispatcher/*</url-pattern>
    </servlet-mapping>

    <resource-ref>
        <res-ref-name>jdbc/MyDataSource</res-ref-name>
        <res-type>javax.sql.DataSource</res-type>
        <res-auth>Container</res-auth>
    </resource-ref>
</web-app>

文件夹结构：

我不建议像本例中那样基于字符串进行注入；您的代码实际上对我来说运行得很好，所以您项目中的其他错误导致了您没有发布的问题。通过使用编译的限定符而不是基于字符串的限定符，可以避免这些问题

因此，与此相反：

@Named("customerController")
public class CustomerController implements Controller {

只需这样做：（如果您只有一个

控制器的实现

）

你完成了。您没有将代码发布到

控制器

，或者如果有多个

控制器

的实现。假设您有多个实现，根据您的需求，有很多方法可以处理它

最简单的：

@Inject
private CustomerController customerController;

更灵活：

@Qualifier
@Retention(RUNTIME)
@Target({FIELD, TYPE})
public @interface Customer {
}

或者，您可能只有多个实现，但需要在应用程序范围内每隔一段时间更改一次实现：

@Inject
private Controller customerController;

然后激活替代方案：

<beans ... >
    <alternatives>
        <class>a1.AnotherCustomerController</class>
    </alternatives>
</beans>

a1.另一个客户控制器

祝你好运！用进一步的问题或跟进回帖

附言：

---

我使用了

@ApplicationScoped

而不是

@Dependent

，因为您的代码似乎没有共享状态

出色的工作为您的问题提供了100%的所需信息。我不知道你为什么会被否决，但你提问的方式令人难以置信。@exabrial我担心我可能包含了太多的信息。也许这就是投票失败的原因。谢谢你的提示。在web.xml中将

metadata complete

设置为

false

，似乎解决了这个问题。但是，我确实打算添加更多的

Controller

实现，然后使用属性文件将表单数据映射到相关的控制器。你提到的注释可能还有用。很高兴你能理解它！

@Inject
@Named("customerController")
private Controller customerController;

@Inject
private Controller customerController;

@ApplicationScoped
public class CustomerController implements Controller {

@Inject
private CustomerController customerController;

@Qualifier
@Retention(RUNTIME)
@Target({FIELD, TYPE})
public @interface Customer {
}

@Inject
@Customer
private Controller customerController;

@ApplicationScoped
@Customer
public class CustomerController implements Controller {

@Inject
private Controller customerController;

@ApplicationScoped
@Default
public class CustomerController implements Controller {

@ApplicationScoped
@Alternative
public class AnotherCustomerController implements Controller {

<beans ... >
    <alternatives>
        <class>a1.AnotherCustomerController</class>
    </alternatives>
</beans>