Authenticator

public abstract class Authenticator extends Object

The class Authenticator represents an object that knows how to obtain authentication for a network connection. Usually, it will do this by prompting the user for information.

Applications use this class by overriding getPasswordAuthentication() in a sub-class. This method will typically use the various getXXX() accessor methods to get information about the entity requesting authentication. It must then acquire a username and password either by interacting with the user or through some other non-interactive means. The credentials are then returned as a PasswordAuthentication return value.

An instance of this concrete sub-class is then registered with the system by calling setDefault(Authenticator). When authentication is required, the system will invoke one of the requestPasswordAuthentication() methods which in turn will call the getPasswordAuthentication() method of the registered object.

All methods that request authentication have a default implementation that fails.

See Also

• setDefault(java.net.Authenticator)
• getPasswordAuthentication()

Nested Class Summary

enum

Authenticator.RequestorType

The type of the entity requesting authentication.

Public Constructor Summary

Authenticator()

Public Method Summary

static PasswordAuthentication	requestPasswordAuthentication(String host, InetAddress addr, int port, String protocol, String prompt, String scheme, URL url, Authenticator.RequestorType reqType) Ask the authenticator that has been registered with the system for a password.
static PasswordAuthentication	requestPasswordAuthentication(InetAddress addr, int port, String protocol, String prompt, String scheme) Ask the authenticator that has been registered with the system for a password.
static PasswordAuthentication	requestPasswordAuthentication(String host, InetAddress addr, int port, String protocol, String prompt, String scheme) Ask the authenticator that has been registered with the system for a password.
synchronized static void	setDefault(Authenticator a) Sets the authenticator that will be used by the networking code when a proxy or an HTTP server asks for authentication.

Protected Method Summary

PasswordAuthentication	getPasswordAuthentication() Called when password authorization is needed.
final String	getRequestingHost() Gets the hostname of the site or proxy requesting authentication, or null if not available.
final int	getRequestingPort() Gets the port number for the requested connection.
final String	getRequestingPrompt() Gets the prompt string given by the requestor.
final String	getRequestingProtocol() Give the protocol that's requesting the connection.
final String	getRequestingScheme() Gets the scheme of the requestor (the HTTP scheme for an HTTP firewall, for example).
final InetAddress	getRequestingSite() Gets the InetAddress of the site requesting authorization, or null if not available.
URL	getRequestingURL() Returns the URL that resulted in this request for authentication.
Authenticator.RequestorType	getRequestorType() Returns whether the requestor is a Proxy or a Server.

Inherited Method Summary

From class java.lang.Object

Object	clone() Creates and returns a copy of this Object.
boolean	equals(Object obj) Compares this instance with the specified object and indicates if they are equal.
void	finalize() Invoked when the garbage collector has detected that this instance is no longer reachable.
final Class<?>	getClass() Returns the unique instance of Class that represents this object's class.
int	hashCode() Returns an integer hash code for this object.
final void	notify() Causes a thread which is waiting on this object's monitor (by means of calling one of the wait() methods) to be woken up.
final void	notifyAll() Causes all threads which are waiting on this object's monitor (by means of calling one of the wait() methods) to be woken up.
String	toString() Returns a string containing a concise, human-readable description of this object.
final void	wait(long timeout, int nanos) Causes the calling thread to wait until another thread calls the notify() or notifyAll() method of this object or until the specified timeout expires.
final void	wait(long timeout) Causes the calling thread to wait until another thread calls the notify() or notifyAll() method of this object or until the specified timeout expires.
final void	wait() Causes the calling thread to wait until another thread calls the notify() or notifyAll() method of this object.

Public Constructors

public Authenticator ()

Public Methods

public static PasswordAuthentication requestPasswordAuthentication (String host, InetAddress addr, int port, String protocol, String prompt, String scheme, URL url, Authenticator.RequestorType reqType)

Ask the authenticator that has been registered with the system for a password.

First, if there is a security manager, its checkPermission method is called with a NetPermission("requestPasswordAuthentication") permission. This may result in a java.lang.SecurityException.

Parameters

host	The hostname of the site requesting authentication.
addr	The InetAddress of the site requesting authorization, or null if not known.
port	the port for the requested connection
protocol	The protocol that's requesting the connection (getRequestingProtocol())
prompt	A prompt string for the user
scheme	The authentication scheme
url	The requesting URL that caused the authentication
reqType	The type (server or proxy) of the entity requesting authentication.

Returns

• The username/password, or null if one can't be gotten.

Throws

SecurityException	if a security manager exists and its checkPermission method doesn't allow the password authentication request.

See Also

• SecurityManager.checkPermission(Permission)
• NetPermission

public static PasswordAuthentication requestPasswordAuthentication (InetAddress addr, int port, String protocol, String prompt, String scheme)

Ask the authenticator that has been registered with the system for a password.

First, if there is a security manager, its checkPermission method is called with a NetPermission("requestPasswordAuthentication") permission. This may result in a java.lang.SecurityException.

Parameters

addr	The InetAddress of the site requesting authorization, or null if not known.
port	the port for the requested connection
protocol	The protocol that's requesting the connection (getRequestingProtocol())
prompt	A prompt string for the user
scheme	The authentication scheme

Returns

• The username/password, or null if one can't be gotten.

Throws

SecurityException	if a security manager exists and its checkPermission method doesn't allow the password authentication request.

See Also

• SecurityManager.checkPermission(Permission)
• NetPermission

public static PasswordAuthentication requestPasswordAuthentication (String host, InetAddress addr, int port, String protocol, String prompt, String scheme)

Ask the authenticator that has been registered with the system for a password. This is the preferred method for requesting a password because the hostname can be provided in cases where the InetAddress is not available.

First, if there is a security manager, its checkPermission method is called with a NetPermission("requestPasswordAuthentication") permission. This may result in a java.lang.SecurityException.

Parameters

host	The hostname of the site requesting authentication.
addr	The InetAddress of the site requesting authentication, or null if not known.
port	the port for the requested connection.
protocol	The protocol that's requesting the connection (getRequestingProtocol())
prompt	A prompt string for the user which identifies the authentication realm.
scheme	The authentication scheme

Returns

• The username/password, or null if one can't be gotten.

Throws

SecurityException	if a security manager exists and its checkPermission method doesn't allow the password authentication request.

See Also

• SecurityManager.checkPermission(Permission)
• NetPermission

public static synchronized void setDefault (Authenticator a)

Sets the authenticator that will be used by the networking code when a proxy or an HTTP server asks for authentication.

First, if there is a security manager, its checkPermission method is called with a NetPermission("setDefaultAuthenticator") permission. This may result in a java.lang.SecurityException.

Parameters

a	The authenticator to be set. If a is null then any previously set authenticator is removed.

Throws

SecurityException	if a security manager exists and its checkPermission method doesn't allow setting the default authenticator.

See Also

• SecurityManager.checkPermission(Permission)
• NetPermission

Protected Methods

protected PasswordAuthentication getPasswordAuthentication ()

Called when password authorization is needed. Subclasses should override the default implementation, which returns null.

Returns

• The PasswordAuthentication collected from the user, or null if none is provided.

protected final String getRequestingHost ()

Gets the hostname of the site or proxy requesting authentication, or null if not available.

Returns

• the hostname of the connection requiring authentication, or null if it's not available.

protected final int getRequestingPort ()

Gets the port number for the requested connection.

Returns

• an int indicating the port for the requested connection.

protected final String getRequestingPrompt ()

Gets the prompt string given by the requestor.

Returns

• the prompt string given by the requestor (realm for http requests)

protected final String getRequestingProtocol ()

Give the protocol that's requesting the connection. Often this will be based on a URL, but in a future JDK it could be, for example, "SOCKS" for a password-protected SOCKS5 firewall.

Returns

• the protocol, optionally followed by "/version", where version is a version number.

See Also

• URL.getProtocol()

protected final String getRequestingScheme ()

Gets the scheme of the requestor (the HTTP scheme for an HTTP firewall, for example).

Returns

• the scheme of the requestor

protected final InetAddress getRequestingSite ()

Gets the InetAddress of the site requesting authorization, or null if not available.

Returns

• the InetAddress of the site requesting authorization, or null if it's not available.

protected URL getRequestingURL ()

Returns the URL that resulted in this request for authentication.

Returns

• the requesting URL

protected Authenticator.RequestorType getRequestorType ()

Returns whether the requestor is a Proxy or a Server.

Returns

• the authentication type of the requestor