java.rmi
Class Naming

java.lang.Object
  extended byjava.rmi.Naming

public final class Naming
extends Object

The Naming class provides methods for storing and obtaining references to remote objects in a remote object registry. Each method of the Naming class takes as one of its arguments a name that is a java.lang.String in URL format (without the scheme component) of the form:

    //host:port/name
 

where host is the host (remote or local) where the registry is located, port is the port number on which the registry accepts calls, and where name is a simple string uninterpreted by the registry. Both host and port are optional. If host is omitted, the host defaults to the local host. If port is omitted, then the port defaults to 1099, the "well-known" port that RMI's registry, rmiregistry, uses.

Binding a name for a remote object is associating or registering a name for a remote object that can be used at a later time to look up that remote object. A remote object can be associated with a name using the Naming class's bind or rebind methods.

Once a remote object is registered (bound) with the RMI registry on the local host, callers on a remote (or local) host can lookup the remote object by name, obtain its reference, and then invoke remote methods on the object. A registry may be shared by all servers running on a host or an individual server process may create and use its own registry if desired (see java.rmi.registry.LocateRegistry.createRegistry method for details).

Since:
JDK1.1
Author:
Ann Wollrath, Roger Riggs
See Also:
Registry, LocateRegistry, LocateRegistry.createRegistry(int)

Nested Class Summary
private static class Naming.ParsedNamingURL
          Simple class to enable multiple URL return values.
 
Constructor Summary
private Naming()
          Disallow anyone from creating one of these
 
Method Summary
static void bind(String name, Remote obj)
          Binds the specified name to a remote object.
private static Registry getRegistry(Naming.ParsedNamingURL parsed)
          Returns a registry reference obtained from information in the URL.
static String[] list(String name)
          Returns an array of the names bound in the registry.
static Remote lookup(String name)
          Returns a reference, a stub, for the remote object associated with the specified name.
private static Naming.ParsedNamingURL parseURL(String str)
          Dissect Naming URL strings to obtain referenced host, port and object name.
static void rebind(String name, Remote obj)
          Rebinds the specified name to a new remote object.
static void unbind(String name)
          Destroys the binding for the specified name that is associated with a remote object.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

Naming

private Naming()
Disallow anyone from creating one of these

Method Detail

lookup

public static Remote lookup(String name)
                     throws NotBoundException,
                            MalformedURLException,
                            RemoteException
Returns a reference, a stub, for the remote object associated with the specified name.

Parameters:
name - a name in URL format (without the scheme component)
Returns:
a reference for a remote object
Throws:
NotBoundException - if name is not currently bound
RemoteException - if registry could not be contacted
AccessException - if this operation is not permitted
MalformedURLException - if the name is not an appropriately formatted URL
Since:
JDK1.1

bind

public static void bind(String name,
                        Remote obj)
                 throws AlreadyBoundException,
                        MalformedURLException,
                        RemoteException
Binds the specified name to a remote object.

Parameters:
name - a name in URL format (without the scheme component)
obj - a reference for the remote object (usually a stub)
Throws:
AlreadyBoundException - if name is already bound
MalformedURLException - if the name is not an appropriately formatted URL
RemoteException - if registry could not be contacted
AccessException - if this operation is not permitted (if originating from a non-local host, for example)
Since:
JDK1.1

unbind

public static void unbind(String name)
                   throws RemoteException,
                          NotBoundException,
                          MalformedURLException
Destroys the binding for the specified name that is associated with a remote object.

Parameters:
name - a name in URL format (without the scheme component)
Throws:
NotBoundException - if name is not currently bound
MalformedURLException - if the name is not an appropriately formatted URL
RemoteException - if registry could not be contacted
AccessException - if this operation is not permitted (if originating from a non-local host, for example)
Since:
JDK1.1

rebind

public static void rebind(String name,
                          Remote obj)
                   throws RemoteException,
                          MalformedURLException
Rebinds the specified name to a new remote object. Any existing binding for the name is replaced.

Parameters:
name - a name in URL format (without the scheme component)
obj - new remote object to associate with the name
Throws:
MalformedURLException - if the name is not an appropriately formatted URL
RemoteException - if registry could not be contacted
AccessException - if this operation is not permitted (if originating from a non-local host, for example)
Since:
JDK1.1

list

public static String[] list(String name)
                     throws RemoteException,
                            MalformedURLException
Returns an array of the names bound in the registry. The names are URL-formatted (without the scheme component) strings. The array contains a snapshot of the names present in the registry at the time of the call.

Parameters:
name - a registry name in URL format (without the scheme component)
Returns:
an array of names (in the appropriate format) bound in the registry
Throws:
MalformedURLException - if the name is not an appropriately formatted URL
RemoteException - if registry could not be contacted.
Since:
JDK1.1

getRegistry

private static Registry getRegistry(Naming.ParsedNamingURL parsed)
                             throws RemoteException
Returns a registry reference obtained from information in the URL.

Throws:
RemoteException

parseURL

private static Naming.ParsedNamingURL parseURL(String str)
                                        throws MalformedURLException
Dissect Naming URL strings to obtain referenced host, port and object name.

Returns:
an object which contains each of the above components.
Throws:
MalformedURLException - if given url string is malformed