Module java.rmi

Interface Registry

  • All Superinterfaces:
    Remote

    public interface Registry
    extends Remote
    Registry is a remote interface to a simple remote object registry that provides methods for storing and retrieving remote object references bound with arbitrary string names. The bind, unbind, and rebind methods are used to alter the name bindings in the registry, and the lookup and list methods are used to query the current name bindings.

    In its typical usage, a Registry enables RMI client bootstrapping: it provides a simple means for a client to obtain an initial reference to a remote object. Therefore, a registry's remote object implementation is typically exported with a well-known address, such as with a well-known ObjID and TCP port number (default is 1099).

    The LocateRegistry class provides a programmatic API for constructing a bootstrap reference to a Registry at a remote address (see the static getRegistry methods) and for creating and exporting a Registry in the current VM on a particular local address (see the static createRegistry methods).

    A Registry implementation may choose to restrict access to some or all of its methods (for example, methods that mutate the registry's bindings may be restricted to calls originating from the local host). If a Registry method chooses to deny access for a given invocation, its implementation may throw AccessException, which (because it extends RemoteException) will be wrapped in a ServerException when caught by a remote client.

    The names used for bindings in a Registry are pure strings, not parsed. A service which stores its remote reference in a Registry may wish to use a package name as a prefix in the name binding to reduce the likelihood of name collisions in the registry.

    Since:
    1.1
    See Also:
    LocateRegistry
    • Field Summary

      Fields 
      Modifier and Type Field Description
      static int REGISTRY_PORT
      Well known port for registry.
    • Method Summary

      All Methods Instance Methods Abstract Methods 
      Modifier and Type Method Description
      void bind​(String name, Remote obj)
      Binds a remote reference to the specified name in this registry.
      String[] list()
      Returns an array of the names bound in this registry.
      Remote lookup​(String name)
      Returns the remote reference bound to the specified name in this registry.
      void rebind​(String name, Remote obj)
      Replaces the binding for the specified name in this registry with the supplied remote reference.
      void unbind​(String name)
      Removes the binding for the specified name in this registry.
    • Field Detail

      • REGISTRY_PORT

        static final int REGISTRY_PORT
        Well known port for registry.
        See Also:
        Constant Field Values
    • Method Detail

      • lookup

        Remote lookup​(String name)
               throws RemoteException,
                      NotBoundException,
                      AccessException
        Returns the remote reference bound to the specified name in this registry.
        Parameters:
        name - the name for the remote reference to look up
        Returns:
        a reference to a remote object
        Throws:
        NotBoundException - if name is not currently bound
        RemoteException - if remote communication with the registry failed; if exception is a ServerException containing an AccessException, then the registry denies the caller access to perform this operation
        AccessException - if this registry is local and it denies the caller access to perform this operation
        NullPointerException - if name is null
      • bind

        void bind​(String name,
                  Remote obj)
           throws RemoteException,
                  AlreadyBoundException,
                  AccessException
        Binds a remote reference to the specified name in this registry.
        Parameters:
        name - the name to associate with the remote reference
        obj - a reference to a remote object (usually a stub)
        Throws:
        AlreadyBoundException - if name is already bound
        RemoteException - if remote communication with the registry failed; if exception is a ServerException containing an AccessException, then the registry denies the caller access to perform this operation (if originating from a non-local host, for example)
        AccessException - if this registry is local and it denies the caller access to perform this operation
        NullPointerException - if name is null, or if obj is null
      • unbind

        void unbind​(String name)
             throws RemoteException,
                    NotBoundException,
                    AccessException
        Removes the binding for the specified name in this registry.
        Parameters:
        name - the name of the binding to remove
        Throws:
        NotBoundException - if name is not currently bound
        RemoteException - if remote communication with the registry failed; if exception is a ServerException containing an AccessException, then the registry denies the caller access to perform this operation (if originating from a non-local host, for example)
        AccessException - if this registry is local and it denies the caller access to perform this operation
        NullPointerException - if name is null
      • rebind

        void rebind​(String name,
                    Remote obj)
             throws RemoteException,
                    AccessException
        Replaces the binding for the specified name in this registry with the supplied remote reference. If there is an existing binding for the specified name, it is discarded.
        Parameters:
        name - the name to associate with the remote reference
        obj - a reference to a remote object (usually a stub)
        Throws:
        RemoteException - if remote communication with the registry failed; if exception is a ServerException containing an AccessException, then the registry denies the caller access to perform this operation (if originating from a non-local host, for example)
        AccessException - if this registry is local and it denies the caller access to perform this operation
        NullPointerException - if name is null, or if obj is null
      • list

        String[] list()
               throws RemoteException,
                      AccessException
        Returns an array of the names bound in this registry. The array will contain a snapshot of the names bound in this registry at the time of the given invocation of this method.
        Returns:
        an array of the names bound in this registry
        Throws:
        RemoteException - if remote communication with the registry failed; if exception is a ServerException containing an AccessException, then the registry denies the caller access to perform this operation
        AccessException - if this registry is local and it denies the caller access to perform this operation