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2010-03-24
Revision History | ||
---|---|---|
Revision 1.1 | 2010-03-18 | MEM |
Revision for the release of jAPS 2.0.10 | ||
Revision 1.0 | 2009-11-26 | MEM |
English translation |
Table of Contents
List of Examples
Table of Contents
The aim of this document is to give a detailed description of the architectural model of jAPS 2.0 and the steps to follow to create a new application service.
This document is for developers aiming to build a new Application Service su jAPS 2.0.
In order to take the maximum advantage of the present document, it is necessary to have a basic knowledge about: the Java platform, the Eclipse IDE, the Apache Tomcat servlet container, the PosgreSQL DBMS and the jAPS 2.0 framework.
Additional informations may be obtained through the following mailing-lists:
<japs-devs@lists.sourceforge.net>
, focused on developers<japs-users@lists.sourceforge.net>
, focused on final usersIs it also possible to refer to the documentation found in the:
We define the jAPS Manager as a part of the jAPS Core which implements a basic system funtionality. A jAPS Manger is also the main handler of that particular functionality.
The main services belong to one of the following groups:
Basic services:
AuthenticationProviderManager: authenticator service..
BaseConfigManager: configuration service. Load the configuration parameters from system database, making it available to the invoker.
CacheManager: cache handler service.
CategoryManager: category handler service.
ControllerManager: this service supervises the execution of a request coming from the client.
GroupManager: group handler.
I18nManager: this service returns the localized strings upon request
KeyGeneratorManager: this service superintends the generation of primary keys
LangManager: this service handles the various languages of the system
NotifyManager: event notification dispatcher service
PageManager: page handler
PageModelManager: this service handles the various page models
RoleManager: role manager
ShowletTypeManager: this service manages the showlets (ShowletTypes) types defined in the system
UrlManager: this manager creates a URL to page of the Portal from essential informations.
UserManager: account manager
ContentManager: contents manager
ContentPageMapperManager: this service manages the map of the contents published in the pages of the portal
LinkResolverManager: this manager resolves the symbolic links
ResourceManager: resources (audio, video, images etc.) handler
SearcheEngineManager: this service creates the indexes of all the objects which will be later parsed by the search engine.
It's important to underline that each service has one and only one instance. The invocation of a service can
be obtained in either two ways: through the "Dependency Injection" technique favored by Spring or using the appropriate
elements of the system like ApsWebApplicationUtils
.
Every jAPS manager is described through a specific interface and every object class access a service always
using the appropriate interface, never invoking the class directly.
The manager (o jAPS Manager) is the only linking point between the system data -whatever their origin is- and the functionality which use them.
An example of service is the PageManager
which manages the tree of the portal pages. Every operation
involving the pages, such as addition, removal, displaying and so on is handled by the PageManager.
Architectural model of the jAPS 2.0
To fully understand this document it's necessary to describe the architectural model of jAPS: jAPS is mainly composed by 3 layers:
Data Access Layer: It is composed by all the elements which superintend the Persistence Layer. The main component are the DAO classes (Data Access Object) which are the only linking element between the framework and the data sources (Database, Filesystem, LDAP service directory etc.)
Business Layer:
This is the core of the system. Here the concept of jAPS service as manager of
every macro functionality, takes place. This layer is built upon the Spring Framework, whose listener, during
the system start-up, initializes all the services and injects them in the web application context as
beans
.
The Business Layer utilizes the Data Access layer to get the data needed, gives to the higher layer
(the Presentation layer) the elements to display and supports it in the execution of actions.
Presentation Layer: The aim of this layer is to build the graphic interfaces which represent the mean through which the users interact with the system. This layer gives a pure View layer (that is, a jsp without any business logic) and a "slim" controller (which checks the consistency of the data submitted and serves the data produced); both of them provide support to the layer below, the Business Layer. In the jAPS framework this layer is divided in two parts: the Portal View (referred as Front-end) and the Administration View (Back-end). These views, which differs by functionality and architecture, are completely independent from each other.
This is the part of the presentation layer where the results of the queries to system services are displayed mainly through the Showlets. Showlets are the preferred method to use to make the system services interact with users. The tasks of the Portal View are to provide services based on the current user permissions (every element of the Portal Layer incorporates the rules which govern the access to services) and to serve content as fast as possible (using content caching mechanism). The portal view is handled by a specialized servlet (ControllerServlet) whose primary target is to invoke a precise succession of services (coherency of the URL, user privilege checks etc) which will finally result in the rendering of the requested page.
This is the area reserved for administration of the various elements of the Portal (Pages, Contents, Resources etc.) whose access is reserved to a restricted pool of users. The view of the Adminstration Area, comprehensive of the controller logic) has been completely redesigned: the reference framework, firmly tied to the Spring framework, is now Struts2. The View has been modified to met the (Italian) Public Administration requisites of accessibility - taking as a firm point the respect of all the W3C standards.
The source files, with the exclusion of the test packages and certain supporting elements (eg. the static resources and the templates directories etc.), are enclosed in two packages:
com.agiletec.aps
:
here can be found all the elements of the Data Access Layer, Business and presentation Layer (the last
limited to the Portal View only)
com.agiletec.apsadmin
:
this package contains all the elements need to manage the presentation layer of the Administration View
WEB-INF
of the web application:
here are contained, including the supporting folders, the usual aps
(which contains
all the jsp and the tld files of the Portal View layer) and apsadmin
(containing all
the jsp files belonging to the Administration Area).
The following paragraphs explain in detail how to create a new service in the jAPS 2.0 framework.
The main objective of the present document is to allow the jAPS-Developers a fast development of new services to integrate with existing ones, without modifying the Base Core sources (java classes, jsp files, configurations, etc).
During the process of the creation of a new service, the following procedure starts from the implementation of the Business and Data Layer of the new functionality.
Active elements: the classes involved are <NAME_OF_THE_HANDLED_OBJECT>Manager (the name of the service) which must extend the AbstractService class. In a similar manner, if the DAO classes are needed, the <NAME_OF_THE_HANDLED_OBJECT>DAO must extend the AbstractDao class.
Create the package, external to the core classes, respecting the same schema used by the core.
Example 4.1. Package Manager Card
If the new service is called Card, the resulting name
will be it.projectname.aps.system.services.card
.
I<NAME_OF_THE_HANDLED_OBJECT>Manager
.
Create the class of the service <NAME_OF_THE_HANDLED_OBJECT>Manager
which extends in turn the
AbstractService and implements the methods declared in the interface seen before.
Example 4.3. Manager Card class
public class CardManager extends AbstractService implements ICardManager { .... }
init
method of the abstract service (which allows the
correct initialization of the service), and the methods declared in the interface properly
Example 4.4. Implementation of the init method
/** * Service initialization */ public void init() throws Exception { ..... }
Example 4.5. Definition of the name of a manager through a constant
public interface MyProjectSystemConstants { public static final String CARD_MANAGER = "CardManager"; ....... }
/WEB-INF/<PROJECT_NAME>/conf/
following
the same pattern used for the configuration files of the core.
The new Manager must be inserted in the Spring context using a syntax similar to the one shown below:
<bean id="CardManager" class="it.projectname.aps.system.services.card.CardManager" parent="abstractService" > </bean>where the id is the value of the constant defined previously.
![]() | Important |
---|---|
Care must be taken in the definition of the bean since it must not match any other existing ids in the system unless we intend to extend an existing service on purpose. |
/WEB-INF/web.xml
and adding
to the xml attribute param-value
of the parameter contextConfigLocation
the
file pattern string WEB-INF/<PROJECT_NAME>/conf/**/**.xml
. This definition must be added in
the last position.
The same pattern must be inserted in method getSpringConfigFilePaths
of the class
test.com.agiletec.aps.ConfigUtils
. This class is used to setup the proper environment
for the test suites; again, the definition must be placed in the last position.
If the new service uses a DAO (Data Access Object) so that it adds new elements in the Data Layer, the first thing to do is to crate an interface Firma del DAO using this declaration I<NAME_OF_THE_HANDLED_OBJECT>DAO and add, in the class which implements that interface, an instance variable of the same type of the newly created one. This variable must have both getter and setter, with the former being rigorously public.
Example 4.6. Methods signature
public void setCardDao(ICardDAO cardDao); protected ICardDAO getCardDao();
Example 4.8. Full definition of the Manager
<bean id="CardManager" class="it.projectname.aps.system.services.card.CardManager" parent="abstractService" > <property name="cardDao"> <bean class="it.projectname.aps.system.services.card.CardDAO" > <property name="dataSource" ref="dataSourceBeanName" /> </bean> </property> </bean>
Every service in the DAO must be tested in its public methods. In other words it's necessary to:
create a java class named <PROJECT_NAME>ConfigUtils (in the package test.it.projectname
)
which extends the class ConfigUtils
; the methods getSpringConfigFilePaths and closeDataSources must be
extended as well. The former provides the path for the configuration files of the new service needed by
Spring, the latter handles the database connection closure of the new datasources.
create a java class <PROJECT_NAME>BaseTestCase (in the package
test.it.projectname.aps
) which extends the class
test.com.agiletec.aps.BaseTestCase
. Override the method getConfigUtils
so that it returns an instance of <PROJECT_NAME>ConfigUtils (that is, the class
previously created).
Create the test classes Test<NAME_OF_THE_HANDLED_OBJECT>Manager and, if needed, the
Test<NAME_OF_THE_HANDLED_OBJECT>DAO in the package test.it.projectname.aps.system.services.<NAME_OF_THE_HANDLED_OBJECT>
Such classes must extend the classes previously created. Remember to test all the public methods
of the new service.
ImyServiceManager myServiceManager = (ImyServiceManager) this.getService(MyProjectSystemConstants.MY_SERVICE_MANAGER);To test a DAO is necessary to create it as Spring does, passing to it the datasource and as every requested bean.
DataSource dataSource = (DataSource) this.getApplicationContext().getBean("dataSourceName"); MyServiceDAO myServiceDao = new MyServiceDAO(); myServiceDao.setDataSource(dataSource);Two databases, namely jAPStestPort and jAPStestServ, are provided for testing purposes. They reflect their "production" counterparts, the jAPSPort and jAPSServ. If the new service requires additional databases they all must have a test and a production version as well.
For every method of the service to test a corresponding method in the appropriate test class must be created:
public void testNomeMetodoDaTestare() { ........ }When creating test methods it's important to plan the restore of the data in the state they were prior the execution of the test(s), whatever the result is. This assures the coherence and the correctness of the following test. You don't want a failed test to cause a succession of failures in different classes which previously were just fine.
If the newly born service alters existing managers (by either integrating or modifying functionalities)
you are strongly advised to avoid modifying the core! Create inside the package
it.projectname.aps.system.services
of your project, a new manager which extends
the existing one. In the Spring configuration file of your service the id of the service must
perfectly match the one of the existing service (of the core of jAPS) that we are going to extend.
Example 4.9. Extension of the User Manager using the same id of the core service (UserManager)
<bean id="UserManager" class="it.projectname.aps.system.services.user.UserManager" parent="abstractService" > <property name="userDAO" > <bean class="it.projectname.aps.system.services.user.UserDAO"> <property name="dataSource" ref="servDataSource" /> </bean> </property> <property name="configManager" ref="BaseConfigManager"/> </bean>
UserManager
substitutes, having the same name, the
one of the core of jAPS.
Remember to insert all the properties found in the declaration of the core bean in the new one.
The most of the Application services will need an administration interface. In the core of jAPS, the class which superintend the interface mechanism are all grouped inside the package com.agiletec.aspadmin. This package in turn contains other sub packages organized (and separated) by functionality; each serves a well determined function whose controls are displayed in the Administration Area. The new service must present the sources to manage the back-end interfaces developed following the same structure used in the core.
Create the package -outside the Core path!- respecting the schema used in jAPS 2.0, as stated earlier.
Example 4.10. Create a package for the Action classes for the Card service
Suppose to have the need to create Actions to handle the Cards (defined in the homonym class):
the resulting name of the package will be: it.projectname.apsadmin.card
.
If our service provides some search function of the object handled by the service we have to create an additional java interface, namely I<NAME_OF_THE_HANDLED_OBJECT>FinderAction. This is the gate to the finder action class.
Create the action class named <NAME_OF_THE_HANDLED_OBJECT>Action which extends the BaseAction and implements the interface above. If needed, create the finder action class which manages the search operations.
Any action class must have a corresponding Spring configuration file; the syntax to use is close to the one shown in the example below.
Example 4.12. Definition of the action bean
<bean id="cardAction" scope=”prototype” class="it.projectname.apsadmin.card.CardAction" parent="abstractBaseAction" > </bean>
![]() | Important |
---|---|
The scope of the bean of the action classes must be "prototype" and care must be taken when defining the bean: it must not match any other bean id of the core, unless we are extending an existing service, as we have already seen. |
/WEB-INF/<PROJECT_NAME>/apsadmin/conf/
.
Once again, make spring aware of the new action by adding the followin string WEB-INF/<PROJECT_NAME>/apasadmin/conf/**/**.xml
in the xml attribute param-value
of the parameter contextConfigLocation
located
in the file /WEB-INF/web.xml
. This definition must be placed in the last position.
Create, at the same level of the interfaces and classes, a xml file which contains the definitions of the actions previously implemented. These definitions follow the Struts2 rules; there is one definition for every action which can be triggered by users from the user interface.
Example 4.13. Action definitions in the file card.xml
<struts> <package name="portalExample_do/Card" namespace="/do/Card" extends="japs-default"> <action name="list" class="cardFindingAction"> <result type="tiles">admin.Card.list</result> <interceptor-ref name="japsDefaultStack"> <param name="requestAuth.requiredPermission">superuser</param> </interceptor-ref> </action> ...... <action name="edit" class="cardAction" method="edit"> <result type="tiles">admin.Card.entry</result> <interceptor-ref name="japsDefaultStack"> <param name="requestAuth.requiredPermission">superuser</param> </interceptor-ref> </action> .... </package> </struts>
Make use of the stack interceptors defined in the file struts.xml
:
japsDefaultStack
:
this is the default for the actions of the Administration view which need specific permissions to be
executed (eg. check for the user permission when accessing the Administration area). This stack does
not enforce validation or range check of the submitted parameters. This stack needs the explicit
declaration of the permission needed to execute the action in the requiredPermission
tag.
japsValidationStack
: extension of the japsDefaultStack with the addition of validation checks.
japsFreeStack
:
This stack is to be used for actions both internal and external to the Administration area, which
require neither permission nor validation checks.
japsFreeValidationStack
: Extension of the japsFreeStack stack with validation check enabled.
Create at the same level of the java interface and action classes the appropriate xml files to define the kind and the number of validation checks to perform. These validation files follow the Struts2 syntax for the validation.
Create a new <PROJECT_NAME>-struts.xml in the root of the source files or, in other word, in the same level of the directory where the struts.xml resides. This file must contain all the references to the configuration files of the new actions of the project.
Example 4.14. Example of actions definition in the file PortalExample.xml
<struts> <include file="it/myprojectname/apsadmin/card/card.xml"/> </struts>
Struts2Config
within the /WEB-INF/web.xml
file. As always
the definition must be inserted in the last position.
The property files reside in the same directory of the newly created Action classes; theese files provide support for the Internationalization (i18n). These file must follow strictly the rules as specified in documentation released in the Struts2 framework website.
In the properties files must be inserted not only the static labels of the jsp files of the user interfaces,
but all the labels correlated to the validation support.
These labels must be provided for both English and Italian language (the file
package_it.properties
and package_en.properties
serve this
purpose).
As for the id of the service beans, the keys of the labels must not match any of the common resources keys contained
in the files global-messages_en.properties
and global-messages_it.properties
.
To avoid problems, you are encouraged to subdivide the label in the following groups:
on menu basis
per titles (h1 e h2)
static strings of the jsp files
string used by the validation files
Create the proper environment and the classes to test new newly created actions. In other words:
create a java class named <PROJECT_NAME>ConfigUtils (or use the class used to test the manager
methods) which extends the class ConfigUtils
; the methods
getSpringConfigFilePaths and closeDataSources must be extended as well. The former provide the path
for the configuration files of the new service needed by Spring, the latter handles the database
connection closure of the new datasources.
Create a java class <PROJECT_NAME>ApsAdminTestCase (inside the package test.it.projectname.apsadmin) which extends the class test.com.agiletec.apsadmin.ApsAdminTestCase, then override the method getConfigUtils (so that it returns an instance of the class previously created) and the setInitParameters (so to load the definition of your actions and all those defined in the same level of the struts.xml)
Create the Action classes named Test<NAME_OF_THE_HANDLED_OBJECT>Action which extends the class of the previous step. If needed create the test class of the action which uses the search engine of your service; always test all the Actions!
All the jsp files composing the user interfaces are located in the directory /WEB-INF/<PROJECT_NAME>/apsadmin/jsp/
.
Example 4.15. jsp of the card manager service
cardFinder.jsp
: this is the interface for the search card service; the search
itself is handled by the Action class CardFinderAction.
entryCard.jsp
generates the Card add/remove interface, handled by the Action
class CardAction.
The (jsp) interfaces must be declared inside the template called main.layout
in the file
/WEB-INF/apsadmin/tiles.xml
which specifies the configuration of the pages being invoked
as a result of the action. Such configuration must obey the rules of Tiles2, a Struts2 plugin.
Define a new Tiles configuration file for the pages, <PROJECT_NAME>-tiles.xml inside the folder
/WEB-INF/<PROJECT_NAME>/apsadmin
.
The pages must extend the main.layout
and the single ids represent the result (in the form of
tiles
type) of every action.
The tiles configuration must be declared within the parameter org.apache.tiles.impl.BasicTilesContainer.DEFINITIONS_CONFIG
of the descritptor file web.xml of the web application. Again, it must be placed in the last position.
To add a new element in the Plugin
menu create in the directory
/WEB-INF/<PROJECT_NAME>/apsadmin/jsp/common/template/
a file named
subMenu.jsp
which contains the new menu item referring to the new application service
(a plugin, in this case)
Then create a new bean (a Spring Object) with id <SERVICE_NAME>SubMenu which refers to the class
PluginSubMenuContainer
; this class has a property called submenuFilePath
whose value
is the path of the subMenu.jsp
just created.
Example 4.16. Declaration of the Menu
<bean id="cardPluginSubMenu" class="com.agiletec.apsadmin.system.plugin.PluginSubMenuContainer" > <property name="subMenuFilePath"> <value>/WEB-INF/demo/apsadmin/jsp/common/template/subMenu.jsp</value> </property> </bean>
Plugin
menu in the
administration area.
If the Application service is going to modify exinsting interfaces for any reason (eg. integration of new modules, link or whatever) you are adviced to avoid any modification of the Core interfaces. Create instead in the tiles configuration file <PROJECT_NAME>-tiles.xml a new definition with the same name of the core interface to override. So the element to modify is simply rewritten from scratch.
Example 4.17. Redefinition of the "Pages Tree" interface
copy the following definition in the files <PROJECT_NAME>-tiles.xml:
<definition extends="main.layout" name="admin.Page.viewTree"> <put-attribute name="title" value="title.pageManagement" /> <put-attribute name="extraResources" value="/WEB-INF/apsadmin/jsp/common/template/extraresources/pageTree.jsp" /> <put-attribute name="body" value="/WEB-INF/<PROJECT_NAME>/apsadmin/jsp/page/pageTree.jsp" /> </definition>where the
admin.Page.viewTree
is the id of the interface of the page tree handler.
Nei limiti del possibile, è sconsigliato utilizzare questa tecnica; nel caso di inserimento nuove
funzionalità che integrano alcune preesistenti,
è consigliato utilizzare la tecnica dei SubMenu
dei Plugin per creare gli
EntryPoint
della funzionalità.
Whenever it's possible please follow these directions; if the new service adds some new functionality
extentending the existing ones, a good practice is to use the submenu technique used for the plugins
so to create the entry point for the new service.
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You may add a passage of up to five words as a Front-Cover Text, and a passage of up to 25 words as a Back-Cover Text, to the end of the list of Cover Texts in the Modified Version. Only one passage of Front-Cover Text and one of Back-Cover Text may be added by (or through arrangements made by) any one entity. If the Document already includes a cover text for the same cover, previously added by you or by arrangement made by the same entity you are acting on behalf of, you may not add another; but you may replace the old one, on explicit permission from the previous publisher that added the old one.
The author(s) and publisher(s) of the Document do not by this License give permission to use their names for publicity for or to assert or imply endorsement of any Modified Version.
You may combine the Document with other documents released under this License, under the terms defined in section 4 above for modified versions, provided that you include in the combination all of the Invariant Sections of all of the original documents, unmodified, and list them all as Invariant Sections of your combined work in its license notice, and that you preserve all their Warranty Disclaimers.
The combined work need only contain one copy of this License, and multiple identical Invariant Sections may be replaced with a single copy. If there are multiple Invariant Sections with the same name but different contents, make the title of each such section unique by adding at the end of it, in parentheses, the name of the original author or publisher of that section if known, or else a unique number. Make the same adjustment to the section titles in the list of Invariant Sections in the license notice of the combined work.
In the combination, you must combine any sections Entitled “History” in the various original documents, forming one section Entitled “History”; likewise combine any sections Entitled “Acknowledgements”, and any sections Entitled “Dedications”. You must delete all sections Entitled “Endorsements”.
You may make a collection consisting of the Document and other documents released under this License, and replace the individual copies of this License in the various documents with a single copy that is included in the collection, provided that you follow the rules of this License for verbatim copying of each of the documents in all other respects.
You may extract a single document from such a collection, and distribute it individually under this License, provided you insert a copy of this License into the extracted document, and follow this License in all other respects regarding verbatim copying of that document.
A compilation of the Document or its derivatives with other separate and independent documents or works, in or on a volume of a storage or distribution medium, is called an “aggregate” if the copyright resulting from the compilation is not used to limit the legal rights of the compilation’s users beyond what the individual works permit. When the Document is included in an aggregate, this License does not apply to the other works in the aggregate which are not themselves derivative works of the Document.
If the Cover Text requirement of section 3 is applicable to these copies of the Document, then if the Document is less than one half of the entire aggregate, the Document’s Cover Texts may be placed on covers that bracket the Document within the aggregate, or the electronic equivalent of covers if the Document is in electronic form. Otherwise they must appear on printed covers that bracket the whole aggregate.
Translation is considered a kind of modification, so you may distribute translations of the Document under the terms of section 4. Replacing Invariant Sections with translations requires special permission from their copyright holders, but you may include translations of some or all Invariant Sections in addition to the original versions of these Invariant Sections. You may include a translation of this License, and all the license notices in the Document, and any Warranty Disclaimers, provided that you also include the original English version of this License and the original versions of those notices and disclaimers. In case of a disagreement between the translation and the original version of this License or a notice or disclaimer, the original version will prevail.
If a section in the Document is Entitled “Acknowledgements”, “Dedications”, or “History”, the requirement (section 4) to Preserve its Title (section 1) will typically require changing the actual title.
You may not copy, modify, sublicense, or distribute the Document except as expressly provided under this License. Any attempt otherwise to copy, modify, sublicense, or distribute it is void, and will automatically terminate your rights under this License.
However, if you cease all violation of this License, then your license from a particular copyright holder is reinstated (a) provisionally, unless and until the copyright holder explicitly and finally terminates your license, and (b) permanently, if the copyright holder fails to notify you of the violation by some reasonable means prior to 60 days after the cessation.
Moreover, your license from a particular copyright holder is reinstated permanently if the copyright holder notifies you of the violation by some reasonable means, this is the first time you have received notice of violation of this License (for any work) from that copyright holder, and you cure the violation prior to 30 days after your receipt of the notice.
Termination of your rights under this section does not terminate the licenses of parties who have received copies or rights from you under this License. If your rights have been terminated and not permanently reinstated, receipt of a copy of some or all of the same material does not give you any rights to use it.
The Free Software Foundation may publish new, revised versions of the GNU Free Documentation License from time to time. Such new versions will be similar in spirit to the present version, but may differ in detail to address new problems or concerns. See Copyleft.
Each version of the License is given a distinguishing version number. If the Document specifies that a particular numbered version of this License “or any later version” applies to it, you have the option of following the terms and conditions either of that specified version or of any later version that has been published (not as a draft) by the Free Software Foundation. If the Document does not specify a version number of this License, you may choose any version ever published (not as a draft) by the Free Software Foundation. If the Document specifies that a proxy can decide which future versions of this License can be used, that proxy’s public statement of acceptance of a version permanently authorizes you to choose that version for the Document.
“Massive Multiauthor Collaboration Site” (or “MMC Site”) means any World Wide Web server that publishes copyrightable works and also provides prominent facilities for anybody to edit those works. A public wiki that anybody can edit is an example of such a server. A “Massive Multiauthor Collaboration” (or “MMC”) contained in the site means any set of copyrightable works thus published on the MMC site.
“CC-BY-SA” means the Creative Commons Attribution-Share Alike 3.0 license published by Creative Commons Corporation, a not-for-profit corporation with a principal place of business in San Francisco, California, as well as future copyleft versions of that license published by that same organization.
“Incorporate” means to publish or republish a Document, in whole or in part, as part of another Document.
An MMC is “eligible for relicensing” if it is licensed under this License, and if all works that were first published under this License somewhere other than this MMC, and subsequently incorporated in whole or in part into the MMC, (1) had no cover texts or invariant sections, and (2) were thus incorporated prior to November 1, 2008.
The operator of an MMC Site may republish an MMC contained in the site under CC-BY-SA on the same site at any time before August 1, 2009, provided the MMC is eligible for relicensing.
To use this License in a document you have written, include a copy of the License in the document and put the following copyright and license notices just after the title page:
Copyright © YEAR YOUR NAME Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.3 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license is included in the section entitled “GNU Free Documentation License”.
If you have Invariant Sections, Front-Cover Texts and Back-Cover Texts, replace the “with… Texts.” line with this:
with the Invariant Sections being LIST THEIR TITLES, with the Front-Cover Texts being LIST, and with the Back-Cover Texts being LIST.
If you have Invariant Sections without Cover Texts, or some other combination of the three, merge those two alternatives to suit the situation.
If your document contains nontrivial examples of program code, we recommend releasing these examples in parallel under your choice of free software license, such as the GNU General Public License, to permit their use in free software.