java.rmi
Class Naming

java.lang.Object
  java.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