引发nullpointerexception的EJB远程客户端：无法获取SerialContextProvider

Question

我有一个无状态bean

 @Stateless
 public class CalculatorImpl implements Calculator {
 private static final long serialVersionUID = 1L;
 @Override
  public int add(int a, int b) {
return a+b;
  }
    @Override
   public int sub(int a, int b) {
return a-b;
   }
   @Override
   public int mul(int a, int b) {
return a*b;
  }
   @Override
    public float div(int a, int b) {
return a/b;
   }
    }

我已经在带有@remote注释的界面的glassfish上部署了这个功能

  @Remote
  public interface Calculator extends Serializable{
  public int add(int a, int b)throws RemoteException;
  public int sub(int a, int b)throws RemoteException;
   public int mul(int a, int b)throws RemoteException;
   public float div(int a, int b)throws RemoteException;
  }

客户端代码：

      MyClient client= new MyClient();
  Properties props = new Properties();
  props.put(Context.INITIAL_CONTEXT_FACTORY, "com.sun.enterprise.naming.SerialInitContextFactory");
  props.setProperty("org.omg.CORBA.ORBInitialHost", "localhost");

  // glassfish default port value will be 3700, 
  // but im using tcpviewer to redirect my 50005 port to 3700
  props.setProperty("org.omg.CORBA.ORBInitialPort", "3700");

  InitialContext context = new InitialContext(props);

 client.cart = (ShoppingCart) context
        .lookup("java:global/EJBDemo2EAR/EJBDemo2/CalculatorImpl!com.java.stateless.Calculator");
System.out.println("In doget");
client.cart.buy("soap", 12);
client.cart.getCartContents();

错误为：java.lang.NullPointerException（位于com.sun.Enterprise.Naming.Impl.SerialContext.GetOrb（位于com.sun.Enterprise.Naming.Impl.SerialContext.GetProviderCacheKey（位于com.sun.Enterprise.Naming.Impl.SerialContext.354)（位于com.sun.Enterprise.Naming.Impl.SerialContext.GetRemoteProvider（位于com.sun.Enterprise.Naming.Impl.SerialContext.GetProvider（位于ing.factory.url.pkgs=com.sun.enterprise.naming,java.naming.factory.state=com.sun.corba.ee.impl.presentation.rmi.jndistatefactoryimpl}[根异常是javax.naming.namingexception：无法获取SerialContext的SerialContextProvider[myenv={org.omg.corba.orbinitialport=3700,

Answer 1

在context.lookup中，只需传递完全限定的接口名称：

client.cart=(ShoppingCart)context.lookup("com.java.stateless.Calculator");