Question

我无法将RMI客户端连接到服务器。所以我有这些类/接口：

    package application;

    import java.sql.ResultSet;

    public interface InterfaceRMI {

        public void insererEtudiant(String requete);
        public void supprimerEtudiant(String requete);
        public ResultSet selectionnerEtudiant(String requete);
    }

服务器类：

    package application;

    import java.rmi.RemoteException;
    import java.rmi.server.UnicastRemoteObject;
    import java.sql.Connection;
    import java.sql.DriverManager;
    import java.sql.ResultSet;
    import java.sql.Statement;

    public class ServeurMySQL extends UnicastRemoteObject implements InterfaceRMI {

        public int port;

        public ServeurMySQL(int port) throws RemoteException {
            this.port = port;
        }


        @Override
        public void insererEtudiant(String requete) {
           // Implementation for insertion 
        }

        @Override
        public void supprimerEtudiant(String requete) {
          // Implementation for delete
        }

        @Override
        public ResultSet selectionnerEtudiant(String requete) {
            // Implementation for selection  
        }
    }

连接测试类：

    package application;

    import java.rmi.registry.LocateRegistry;
    import java.rmi.registry.Registry;

    public class test {

        public static void main(String[] args) {
             try {          
                Registry r = LocateRegistry.getRegistry(1098);

                InterfaceRMI serveur = (InterfaceRMI) (r.lookup("serveurMySQL"));

            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    }

当我用InterfaceRMI serveur = (InterfaceRMI) (r.lookup("serveurMySQL"));替换r.lookup("serveurMySQL");行时，我没有得到异常，我知道连接有效，问题只是演员。但我不知道如何解决它。

该例外如下：

    java.lang.ClassCastException: com.sun.proxy.$Proxy0 cannot be cast to application.InterfaceRMI
at application.test.main(test.java:13)

P.S：RMI服务器启动没有任何问题。

Answer 1

第一：

 public interface InterfaceRMI

必须是

 public interface InterfaceRMI extends Remote

第二

InterfaceRMI中的每个方法都必须声明throws RemoteException

Java RMI Client遇到ClassCastException

1 个答案: