How to get the current logged in user in liferay

There are more than one way to do this. Let's look at some of the options available.

1. User user = (User) request.getAttribute(WebKeys.USER);
   The User class is the Liferay's model User class.
   
   
2. ThemeDisplay td  = (ThemeDisplay) request.getAttribute( WebKeys.THEME_DISPLAY );
   User user = td.getUser();
   
   This ' ThemeDisplay 'class can be used to get various information about the portal page,user and theme. Classes ThemeDisplay, User and WebKeys are available in portal-service.jar
   
   
3. User currentUser = PortalUtil.getUser( request );
   
   The 'PortalUtil' has various utility functions , which come handy during Liferay Programming. This is also a part of the Portal-service.jar.
   
   
4. LiferayFacesContext liferayFacesContext = LiferayFacesContext.getInstance();
   User currentUser=liferayFacesContext.getUser();
   
   The class 'PortalFacesContext' has been renamed to 'LiferayFacesContext'.This class exists in order to assist with migrating old JSF 1.2 based projects from the legacy PortletFaces-Tools project to the new LiferayFaces project.
   
   Hope It helps you in your portal programming. Happy Coding :)
   
   
   

ProcessAction Method

ProcessAction() Method

The JSR-168 Specification defines a portlet container that manages portlets.Each portlet’s life cycle contain some specific methods as per JSR-168 namely init(),ProcessAction(),destroy() method etc. . The portlet developer can implement these methods to provide the desired functionality.Among all the life-cycle methods of a portlet one of the most important method is the ProcessAction() method.This ProcessAction() method is Called after the user submits changes to a jsr-168 compliant portlet. It is Intended to process input from a user Interaction.The user must interact with the portlet giving some or the other kind of data to it which must be processed by a portlet.This way we can say that the portlet processing is done in the ProcessAction() method.Even if one tries to maximize the size of the portlet window it calls the ProcessAction() method.

public void processAction(ActionRequest request, ActionResponse response)
throws PortletException, IOException
{
}

The processAction() method is called only by the ActionURL. The other URL i.e RenderURL doesnt invoke the processAction() method.When the form submit button is pressed, the action url is used. The action url indicates to the portal that it is an action request. Responding to the action request, the portal invokes the processAction() method before invoking the render() method.

The request values are obtained from the actionURL in the following way

public void processAction(ActionRequest request, ActionResponse response)
throws PortletException, IOException
{
// get the values submitted with the form

String identity = request.getParameter("parameter1");
String color = request.getParameter("parameter2");

......
}

the way we set the render parameters for the render() method is

public void processAction(ActionRequest request, ActionResponse response)
throws PortletException, IOException
{

......

response.setRenderParameter("parameter1", value1);
response.setRenderParameter("parameter2", value2);
}