EJB 注入 - JNDI 查找失败

Question

所以我开始使用 Netbeans 8.2 开发 Java EE 企业应用程序。这是关于一家商店，你有一个购物车，你必须正确地存储每个客户的会话。

在 NetBeans 中我有：Shop-ejb 和 Shop-war。

Shop-ejb 包含以下类:

CartLocal.java

package cart;

@Local
public interface CartLocal{
}

CartBean.java

package cart;

@Stateful
@StatefulTimeout(unit = TimeUnit.MINUTES, value = 20)
public class CartBean implements CartLocal{
}

然后，Shop-war 包含以下 servlet：

Servlet.java

import cart.CartLocal;
import java.io.*;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.naming.InitialContext;
import javax.naming.NamingException;
import javax.servlet.*;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.*;

@WebServlet(name = "Servlet", urlPatterns = {"/Servlet"})
public class Servlet extends HttpServlet {

private static final String CARRITO_SESSION_KEY = "shoppingCart";

public Servlet() {
    super();
}

@Override
public void doGet(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException {
    CartLocal carrito = (CartLocal) request.getSession().getAttribute(CARRITO_SESSION_KEY);

    try {
        if (carrito == null) {
            InitialContext ic = new InitialContext();
            carrito = (CartLocal) ic.lookup("java:global/Shop/Shop-ejb/CartBean!cart.CartLocal");

            request.getSession().setAttribute(CARRITO_SESSION_KEY, carrito);
        }
    } catch (NamingException ex) {
        Logger.getLogger(Servlet.class.getName()).log(Level.SEVERE, null, ex);
    }
}

我正在使用 GlasshFish，当我访问 http://localhost:8080/Shop-war/Servlet 时，我在 NetBeans 控制台上收到以下错误：

Grave:   javax.naming.NamingException: Lookup failed for 'java:global/Shop/Shop-ejb/CartBean!cart.CartLocal' in SerialContext[myEnv={java.naming.factory.initial=com.sun.enterprise.naming.impl.SerialInitContextFactory, java.naming.factory.state=com.sun.corba.ee.impl.presentation.rmi.JNDIStateFactoryImpl, java.naming.factory.url.pkgs=com.sun.enterprise.naming} [Root exception is javax.naming.NameNotFoundException: Shop]

我知道 lookup 失败了，但我尝试了多种方法，但没有结果。希望你能帮助我。

Answer 1

您需要在 web.xml 上设置一个 <ejb-local-ref> 标签：

例如：

<ejb-local-ref>
        <ejb-ref-name>CartLocal</ejb-ref-name>
        <ejb-ref-type>Session</ejb-ref-type>
        <local>cat.CartLocal</local>
        <ejb-link>CartLocal</ejb-link>
</ejb-local-ref>

并通过查找访问：

try {
        if (carrito == null) {
            InitialContext ic = new InitialContext();
            carrito = (CartLocal) ic.lookup("java:comp/env/CartLocal");

            request.getSession().setAttribute(CARRITO_SESSION_KEY, carrito);
        }
    } catch (NamingException ex) {
        Logger.getLogger(Servlet.class.getName()).log(Level.SEVERE, null, ex);
    }

EJB 注入 - JNDI 查找失败

EJB injection - JNDI lookup fails

java

lookup

netbeans

jndi

jakarta-ee