General

General Which version of Pluto should I use? Pluto 1.0.1 is the most recent distribution. This version of Pluto passes all of the TCK tests. I've seen references to both Pluto 1.0.1 and Pluto 1.1. It seems as though both are being developed at the same time. What is the difference between the two versions?

You're right. Pluto 1.0.1 is the current release. Pluto 1.0.x is based off of the code base which was originally donated to the ASF by IBM. The first release candidate in this series was published on October 8, 2004.

Around the same time that this release occured Pluto 1.1.0-ALPHA was imported into our source repository. The 1.1.x series is a refactoring/rewrite of Pluto. It's entire purpose is to simplify the container and make it easier for both Portlet Developers and Portal Developers looking to embed Pluto into their portal to use Pluto. The 1.1.x series has made great progress and currently passes all of the tests available in the Pluto Testsuite. See the Pluto 1.1 documentation for more details.

Do Pluto Versions correspond with Portlet Specification Versions. No. See the Pluto home page for a mapping of Pluto versions to Portlet Specification versions. Portlets and Deployment Why can't I get the Javaworld bookmark example to work with Pluto?

The Javaworld examples are based on the Proposed Final Draft of JSR-168. The final specification included several changes, including some changes to the xsd.

Please see the message archivesfor a modified version of this example which will work with Pluto.

Is Pluto a fully functional portal implementation?

No, Pluto is a Portlet Container. If you are looking for a Portal implementation, try checking out Jetspeed.

Need more information about the difference between a Portal and a Portlet Container? Take a look at this question.

How do I use the Admin Portlet Application to deploy custom portlets?

Click on the Admin link on the Pluto navigation bar and select the Help mode (help link) in the Deploy War Admin Portlet. The resulting page will display information on the deployment of custom portlets and troubleshooting issues with deployment.

I deployed a custom portlet and Pluto crashed! What do I do?

If deployment of a portlet causes an error that breaks Pluto, manually undeploy the portlet by removing its record from portletentityregistry.xml, pageregistry.xml and portletcontexts.txt in the webapps/pluto/WEB-INF/data directory and restart Pluto.

Also take a look at the log files.

Embedding Pluto I'd like to embed Pluto into my Portal. How do I start? Take a look at the Developer documentation on the website. This has an integration and architecture guide. Additionally we suggest that you look at Jetspeed for an example of how it can be done. We readily admit that this embeding documentation may be a little sparse and welcome any documentation patches. What are the required services that must be implemented by a Portal wanting to embed Pluto?

Information Provider
Factory Manager Service
Log Services

What services are optional when integrating Pluto?

Property Manager Service
Dynamic Title Service

Architecture, Design, and Implementation What is the difference between a Portal and a Portlet Container?

This question was answered on the developer list in the following way:

Date: Tue, 11 Nov 2003 15:21:32 -0600

From: Craig Walls [wallsc.AT.michaels.DOT.com]

Subject: setRenderParameter

Content-Type: text/plain; charset=us-ascii

This question seems to come up every other day. Perhaps this should be a FAQ? Let me attempt to answer it...

Pluto is a JSR-168 compliant portlet container. That means that it provides a place for portlets to reside, but nothing else. Think of it this way: A portlet container (which is what Pluto is) is to portlets what an aquarium is to fish.

Pluto comes with a minimal portal implementation. A portal implementation builds on top of the base container providing additional features which may vary from implementation to implementation. Layout and security are features that may be provided by a portal implementation, but they are in addition to what the container provides. Using the fish analogy again, a portal is to a portlet container what decorations are to an aquarium.

That said, a portlet container provides the basic necessities required for portlets to live, just as an aquarium provides water (and a barrier to contain the water) for fish. A portal implementation provides extra stuff in addition to the portlet container just as an aquarium may have plants, rocks, and tiny little treasure chests that open and close. The fish can survive without the extras, just as a portlet can survive without security or some fancy layout engine. But the fish sure do look much nicer when surrounded with the extra stuff, just as portlets are much more useful when used alongside extra portal features.

Date:	Tue, 11 Nov 2003 15:21:32 -0600
From:	Craig Walls [wallsc.AT.michaels.DOT.com]
Subject:	setRenderParameter
Content-Type:	text/plain; charset=us-ascii
This question seems to come up every other day. Perhaps this should be a FAQ? Let me attempt to answer it... Pluto is a JSR-168 compliant portlet container. That means that it provides a place for portlets to reside, but nothing else. Think of it this way: A portlet container (which is what Pluto is) is to portlets what an aquarium is to fish. Pluto comes with a minimal portal implementation. A portal implementation builds on top of the base container providing additional features which may vary from implementation to implementation. Layout and security are features that may be provided by a portal implementation, but they are in addition to what the container provides. Using the fish analogy again, a portal is to a portlet container what decorations are to an aquarium. That said, a portlet container provides the basic necessities required for portlets to live, just as an aquarium provides water (and a barrier to contain the water) for fish. A portal implementation provides extra stuff in addition to the portlet container just as an aquarium may have plants, rocks, and tiny little treasure chests that open and close. The fish can survive without the extras, just as a portlet can survive without security or some fancy layout engine. But the fish sure do look much nicer when surrounded with the extra stuff, just as portlets are much more useful when used alongside extra portal features.

Want a more technical answer? architectural overview for a more complete description

Configuration How do I configure the pluto portal?

Firstly, please understand that the pluto portal is only intended to be demonstration of how to use pluto-the-container in a portal. The layout of the portal is controlled by two files, WEB-INF\data\pageregistry.xml and WEB-INF\data\portletentityregistry.xml. An explaination for the use of these files follows:

Date: Tue, 11 Nov 2003 02:05:43 +0800

From: Koh Choong Yong [dunpanic.AT.mailhost.DOT.net]

Subject: Re: portletentityregistry.xml and pageregistry.xml

Content-Type: charset=ISO-8859-1; format=flowed

pageregistry.xml describes the layout of the portal in pluto. If you replace the correct sections in the default pageregistry.xml file with the following fragment, you will see that the 2 portlets are displayed one on top of another instead of side-by-side. The attribute for "value" in the <property> tag is a reference to the application id and portlet id in portletentityregistry.xml (see discussion below). <fragment name="row" type="row"> <fragment name="col1" type="column"> <fragment name="p1" type="portlet"> <property name="portlet" value="3.1"/> </fragment> </fragment> </fragment> <fragment name="row2" type="row"> <fragment name="col2" type="column"> <fragment name="p2" type="portlet"> <property name="portlet" value="4.1"/> </fragment> </fragment> </fragment> portletentityregistry.xml describes the portlets available in the portal.

Each <application> tag defines one application (corresponding to one web-app on the portal container), which can contain multiple <portlet> tags. The "id" attribute in this tag identifies the application, and it does not necessary needs to be numeral.

The <definition-id> tag within the <application> refers to the name of the web-app that contains the portlets in this application.

Each <portlet> tag defines one portlet. Similarly the "id" attribute in this tag identifies the portlet. Note that the application id concatenated with the portlet id will be mapped to the "value" attribute in the <proprety> tag in pageregistry.xml

The <definition-id> within the <portlet> is a concatenated id string identifying the portlet within the application. This is a reference to the <portlet-name> tag in the portlet.xml in the respective web-app. In the default setting, <definition-id>testsuite.TestPortlet2</definition-id> the portlet referred to was the TestPortlet2 portlet within the testsuite web-app.

Each <preferences> tag within the <portlet> tag defines name/value pairs for the PorletPreferences. These values can be retrieved within the JSPs using the following code fragment: PortletPreferences preferences = renderRequest.getPreferences(); String testPermanence = preferences.getValue("TEST_PERMANENCE", "Default"); out.println(testPermanence);

Date:	Tue, 11 Nov 2003 02:05:43 +0800
From:	Koh Choong Yong [dunpanic.AT.mailhost.DOT.net]
Subject:	Re: portletentityregistry.xml and pageregistry.xml
Content-Type:	charset=ISO-8859-1; format=flowed
pageregistry.xml describes the layout of the portal in pluto. If you replace the correct sections in the default pageregistry.xml file with the following fragment, you will see that the 2 portlets are displayed one on top of another instead of side-by-side. The attribute for "value" in the <property> tag is a reference to the application id and portlet id in portletentityregistry.xml (see discussion below). <fragment name="row" type="row"> <fragment name="col1" type="column"> <fragment name="p1" type="portlet"> <property name="portlet" value="3.1"/> </fragment> </fragment> </fragment> <fragment name="row2" type="row"> <fragment name="col2" type="column"> <fragment name="p2" type="portlet"> <property name="portlet" value="4.1"/> </fragment> </fragment> </fragment> portletentityregistry.xml describes the portlets available in the portal. Each <application> tag defines one application (corresponding to one web-app on the portal container), which can contain multiple <portlet> tags. The "id" attribute in this tag identifies the application, and it does not necessary needs to be numeral. The <definition-id> tag within the <application> refers to the name of the web-app that contains the portlets in this application. Each <portlet> tag defines one portlet. Similarly the "id" attribute in this tag identifies the portlet. Note that the application id concatenated with the portlet id will be mapped to the "value" attribute in the <proprety> tag in pageregistry.xml The <definition-id> within the <portlet> is a concatenated id string identifying the portlet within the application. This is a reference to the <portlet-name> tag in the portlet.xml in the respective web-app. In the default setting, <definition-id>testsuite.TestPortlet2</definition-id> the portlet referred to was the TestPortlet2 portlet within the testsuite web-app. Each <preferences> tag within the <portlet> tag defines name/value pairs for the PorletPreferences. These values can be retrieved within the JSPs using the following code fragment: PortletPreferences preferences = renderRequest.getPreferences(); String testPermanence = preferences.getValue("TEST_PERMANENCE", "Default"); out.println(testPermanence);

Also note that since Pluto 1.0.1-rc2, another configuration file, portletcontexts.txt, has been included in the Pluto portal. The Portlet Contexts file ($PLUTO_HOME/WEB-INF/data/portletcontexts.txt) lists the webapp contexts for each portlet application that runs in Pluto. Each portlet app has a line in this file corresponding to a path and starting with a slash ('/'). In Tomcat, this path is the value of the 'path' attribute of the 'Context' element in a context XML descriptor in $TOMCAT_HOME/conf/Catalina/localhost (or another 'conf' subdirectory).

How do I make Application Scoped Session Attibutes work? (Do I need to configure Tomcat 5.5 differently?)

Application Scoped Session Attibutes only work in Tomcat 5.5.

In order to enable them on in Tomcat 5.5, you will need to modify your connector configuration. Specifically, set the parameter "emptySessionPath" to true in your connector config in the server.xml.

Note: This setting incorporated into the binary distribution of Pluto since version 1.0.1-RC3..

Common Problems Pluto is driving me crazy! How do I find out what went wrong?

It's a good idea to check the date-stamped pluto.log file in the logs directory to help debug any problems you are having with Pluto. Other log files in that directory might also be helpful. Look at the timestamp of the log files and check them in reverse chronological order.

NullPointerException: org.apache.pluto.invoker.impl.PortletInvokerImpl.invoke

This is usually because pluto cannot load classes for a portlet.

Common causes include:

Cross context dispatching is not turned on for both the pluto portal and your portlet application
The Portlet application has not been installed properly. Use the Maven task or the Admin Portlet Application to install the portlet application properly