If the user-attribute is not defined for the current user it will not show up in the Map.

The value is javax.portlet.userinfo. 

 public Object getAttribute(String name)
Returns the value of the named attribute as an Object,
or null if no attribute of the given name exists.

Attribute names should follow the same conventions as package
names. This specification reserves names matching java.*,
and javax.*.

In a distributed portlet web application the Object
needs to be serializable.

 public Enumeration getAttributeNames()
Returns an Enumeration containing the
names of the attributes available to this request.
This method returns an empty Enumeration
if the request has no attributes available to it.

 public String getAuthType()
Returns the name of the authentication scheme used for the
connection between client and portal,
for example, BASIC_AUTH, CLIENT_CERT_AUTH,
a custom one or null if there was no authentication.

 public String getContextPath()
Returns the context path which is the path prefix associated with the deployed
portlet application. If the portlet application is rooted at the
base of the web server URL namespace (also known as "default" context),
this path must be an empty string. Otherwise, it must be the path the
portlet application is rooted to, the path must start with a '/' and
it must not end with a '/' character.

To encode a URL the PortletResponse#encodeURL  method must be used.

 public Locale getLocale()
Returns the preferred Locale in which the portal will accept content.
The Locale may be based on the Accept-Language header of the client.

 public Enumeration getLocales()
Returns an Enumeration of Locale objects indicating, in decreasing
order starting with the preferred locale in which the portal will
accept content for this request.
The Locales may be based on the Accept-Language header of the client.

 public String getParameter(String name)
Returns the value of a request parameter as a String,
or null if the parameter does not exist. Request parameters
are extra information sent with the request. The returned parameter
are "x-www-form-urlencoded" decoded.

Only parameters targeted to the current portlet are accessible.

This method should only be used if the
parameter has only one value. If the parameter might have
more than one value, use #getParameterValues .

If this method is used with a multivalued
parameter, the value returned is equal to the first value
in the array returned by getParameterValues.

 public Map getParameterMap()
Returns a Map of the parameters of this request.
Request parameters are extra information sent with the request.
The returned parameters are "x-www-form-urlencoded" decoded.

The values in the returned Map are from type
String array (String[]).

If no parameters exist this method returns an empty Map.

 public Enumeration getParameterNames()
Returns an Enumeration of String
objects containing the names of the parameters contained
in this request. If the request has
no parameters, the method returns an
empty Enumeration.

Only parameters targeted to the current portlet are returned.

 public String[] getParameterValues(String name)
Returns an array of String objects containing
all of the values the given request parameter has, or
null if the parameter does not exist.
The returned parameters are "x-www-form-urlencoded" decoded.

If the parameter has a single value, the array has a length
of 1.

 public PortalContext getPortalContext()
Returns the context of the calling portal.

 public PortletMode getPortletMode()
Returns the current portlet mode of the portlet.

 public PortletSession getPortletSession()
Returns the current portlet session or, if there is no current session,
creates one and returns the new session.

Creating a new portlet session will result in creating
a new HttpSession on which the portlet session is based on.

 public PortletSession getPortletSession(boolean create)
Returns the current portlet session or, if there is no current session
and the given flag is true, creates one and returns
the new session.

If the given flag is false and there is no current
portlet session, this method returns null.

Creating a new portlet session will result in creating
a new HttpSession on which the portlet session is based on.

 public PortletPreferences getPreferences()
Returns the preferences object associated with the portlet.

 public Enumeration getProperties(String name)
Returns all the values of the specified request property
as a Enumeration of String objects.

If the request did not include any propertys
of the specified name, this method returns an empty
Enumeration.
The property name is case insensitive. You can use
this method with any request property.

 public String getProperty(String name)
Returns the value of the specified request property
as a String. If the request did not include a property
of the specified name, this method returns null.

A portlet can access portal/portlet-container specific properties
through this method and, if available, the
headers of the HTTP client request.

This method should only be used if the
property has only one value. If the property might have
more than one value, use #getProperties .

If this method is used with a multivalued
parameter, the value returned is equal to the first value
in the Enumeration returned by getProperties.

 public Enumeration getPropertyNames()
Returns a Enumeration of all the property names
this request contains. If the request has no
properties, this method returns an empty Enumeration.

 public String getRemoteUser()
Returns the login of the user making this request, if the user
has been authenticated, or null if the user has not been authenticated.

 public String getRequestedSessionId()
Returns the session ID indicated in the client request.
This session ID may not be a valid one, it may be an old
one that has expired or has been invalidated.
If the client request
did not specify a session ID, this method returns
null.

 public String getResponseContentType()
Returns the portal preferred content type for the response.

The content type only includes the MIME type, not the
character set.

Only content types that the portlet has defined in its
deployment descriptor are valid return values for
this method call. If the portlet has defined
'*' or '* / *' as supported content
types, these may also be valid return values.

 public Enumeration getResponseContentTypes()
Gets a list of content types which the portal accepts for the response.
This list is ordered with the most preferable types listed first.

The content type only includes the MIME type, not the
character set.

Only content types that the portlet has defined in its
deployment descriptor are valid return values for
this method call. If the portlet has defined
'*' or '* / *' as supported content
types, these may also be valid return values.

 public String getScheme()
Returns the name of the scheme used to make this request.
For example, http, https, or ftp.
Different schemes have different rules for constructing URLs,
as noted in RFC 1738.

 public String getServerName()
Returns the host name of the server that received the request.

 public int getServerPort()
Returns the port number on which this request was received.

 public Principal getUserPrincipal()
Returns a java.security.Principal object containing the name of the
current authenticated user.

 public WindowState getWindowState()
Returns the current window state of the portlet.

 public boolean isPortletModeAllowed(PortletMode mode)
Returns true, if the given portlet mode is a valid
one to set for this portlet in the context
of the current request.

 public boolean isRequestedSessionIdValid()
Checks whether the requested session ID is still valid.

 public boolean isSecure()
Returns a boolean indicating whether this request was made
using a secure channel between client and the portal, such as HTTPS.

 public boolean isUserInRole(String role)
Returns a boolean indicating whether the authenticated user is
included in the specified logical "role". Roles and role membership can be
defined using deployment descriptors. If the user has not been
authenticated, the method returns false.

 public boolean isWindowStateAllowed(WindowState state)
Returns true, if the given window state is valid
to be set for this portlet in the context
of the current request.

 public  void removeAttribute(String name)
Removes an attribute from this request. This method is not
generally needed, as attributes only persist as long as the request
is being handled.

Attribute names should follow the same conventions as
package names. Names beginning with java.*,
javax.*, and com.sun.* are
reserved for use by Sun Microsystems.

 public  void setAttribute(String name,
    Object o)
Stores an attribute in this request.

Attribute names should follow the same conventions as
package names. Names beginning with java.*,
javax.*, and com.sun.* are
reserved for use by Sun Microsystems.

 If the value passed into this method is null,
the effect is the same as calling #removeAttribute .