Objective:
Access liferay database services in themes. Means
access Locals Service and Service classes in liferay themes.
Generally some time we need to show some dynamic
data in theme, the data may be stored in any table in liferay database .When we
get such requirement we need to access database from vm files.
In theme level liferay
have given service locater feature to access database services.
Here we are talking about theme means we are access
liferay services in portal_normal.vm file or other VM (velocity) files which is in liferay
themes.
In liferay themes all VM (velocity) files available in
templates
directory. One of the core velocity file is portal_normal.vm.
Liferay already providing many default velocity variables
in theme level such as
$theme_display, $portlet_display, $layout, $company
and $user.
These variables we can see in init.vm file we can use
these variables anywhere in theme vm files when we include vm file in our
working velocity file.
Liferay already include this in portal_notmal.vm
file so that we can use any variable which is available in init.vm
Information
about velocity
Velocity is a Java-based template engine. It permits
anyone to use a simple yet powerful template language to reference objects
defined in Java code.
Liferay uses velocity templates to aggregate dynamic
content of web page.
Here all variable which starts with $ symbol
The following is link to know more about velocity
Declare
variable and assign value
#set(
$a = "Velocity" )
Print
variable
<html>
<body>
#set( $foo = "Velocity" )
Hello $foo World!
</body>
<html>
|
In liferay we can see many declaration of variables
in init.vm
file for example as follows
#set
($user_name = $user.getFullName())
To print user Name
Hi I am $user_name
Note:
Whenever it find the $ it will interpret as velocity variable by velocity engine while
rendering.
This is enough for us to understand about velocity.
Now
accessing liferay data base services in themes
- Make it available of service jar file in liferay global class path
- Use velocity service locater to find data base service in theme
Make
it available of service jar file in liferay global class path
Foremost thing is your service jar file should be available
in liferay
portal global class path
Means liferay portal service (portal-service.jar) available in liferay portal global class path. By
default this jar file available in global lib directory of portal.
For
Tomcat:
The following is liferay portal global class path
tomcat-7.0.27\lib\ext
|
If any jar file which
is available in tomcat-7.0.27\lib\ext path then it can be available to liferay
portal and plug-in portlets too.
By default liferay portal service jar file
available in global lib so we can access all liferay portal services such as UserLocalService,GrouopLocalService
and LayoutLolcaServices.
Note:
There are
many services available in liferay portal level all clasess you can find in portal-service.jar the following
packages com.liferay.portal.service.
For
JBoss:
The following is liferay portal global class path
jboss-7.1.1\modules\com\liferay\portal\main
|
When we work with Liferay JBoss Server this is something different from tomcat
server.
For JBoss the service jar file should available in following
location then it will be treated as global jar so that all liferay portlets can
access these classes.
jboss-7.1.1\modules\com\liferay\portal\main
Once we place the jar in the location we need to entry
the jar file name in module.xml file. The module.xml
also in same location i.e. jboss7.1.1\modules\com\liferay\portal\main
Example for entries like follows
<resource-root
path="portal-service.jar" />
|
module.xml
file
<module
xmlns="urn:jboss:module:1.0"
name="com.liferay.portal">
<resources>
<resource-root
path="hsql.jar" />
<resource-root
path="jtds.jar" />
<resource-root
path="portal-service.jar" />
<resource-root
path="portlet.jar" />
<resource-root
path="postgresql.jar" />
<resource-root
path="mysql.jar" />
<resource-root
path="ojdbc6.jar" />
</resources>
<dependencies>
<module
name="javax.api" />
<module
name="javax.mail.api" />
<module
name="javax.servlet.api" />
<module
name="javax.servlet.jsp.api" />
<module
name="javax.transaction.api" />
</dependencies>
</module>
|
Note:
Liferay by default make the portal services in global
class path level in JBoss .
So we need not do anything and we can use directly
all portal service which in portal-service.jar file.
Use
velocity service locater to find data base service in theme
We can access any portal service in them i.e. in portal_noraml.vm
file or other vm files in liferay. Because
liferay already provided porta-service.jar file in global class path , so
we can access in liferay themes.
In Liferay theme all vm files included in portal_noraml.vm
file this is core vm file for liferay
to aggregate all web page content.
If you use any vm file then it should be included in
portal_noram.vm
file then only it will be rendered.
To access services in them liferay provided service
locater in velocity by using this we can get the services in themes.
We have default velocity variable $serviceloacater we can use this variable
to get the service.
The
following is example code
#set
($userLocalService=
$serviceLocator.findService("com.liferay.portal.service.UserLocalService"))
|
In above code we get the user Service and make sure
we have to use full qualified path of java class means class name including
package name.
Example like this
com.liferay.portal.service.UserLocalService
this
is nothing but com.liferay.portal.service.UserLocalService.java
class in portal-service.jar file.
Once we get the service object we can apply any
method which available in service class.
Example
code as follows
#set
($userLocalService= $serviceLocator.findService("com.liferay.portal.service.UserLocalService"))
#set
($user =
$userLocalService.getUserById($request.get("theme-display").get("user-id")))
#set
($emailAddress = $user.getEmailAddress())
|
Now we can simple print email address like this in portal_noram.vm
file as follows
<h1>$emailAddress</h1>
Note:
This just example snippet I showed and we already
have direct $user object in theme we
can use directly that to get user information.
Examples
for Services in portal
#set
($userLocalService= $serviceLocator.findService("com.liferay.portal.service.UserLocalService"))
#set
($groupLocalService= $serviceLocator.findService("com.liferay.portal.service.GroupLocalService"))
#set
($layoutLocalService= $serviceLocator.findService("com.liferay.portal.service.LayoutLocalService"))
#set
($roleLocalService= $serviceLocator.findService("com.liferay.portal.service.RoleLocalService"))
|
Like this we can access any portal services in portal_normal.vm
file
Accessing
plug-in portlet services in themes
We already know to access portal services but some
time we may get requirement to access plug-in portlet services that is our
custom services.
The
following are the steps
- Create plug-in portlet using Liferay IDE with eclipse.
- Write entities in service.xml file
- Run service builder
- Once service builder successfully run then you will get service jar file in plug-in portlet WEB-INF/lib directory.
- Copy the plug-in portlet service jar file and place this into liferay global lib directory based on your liferay server (JBoss/Tomcat)
- Remove service jar file from plug-in portlet WEB-INF/lib directory
- Now deploy portlet and portlet should be successfully deployed
- Now use service locater to get the plug-in service in theme or portal_normal.vm
Example:
Portlet Name: Student-portlet
Table Name: Student
service.xml
file as follows
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE service-builder PUBLIC
"-//Liferay//DTD Service Builder
6.1.0//EN"
"http://www.liferay.com/dtd/liferay-service-builder_6_1_0.dtd">
<service-builder package-path="com.meera.db">
<author>E5410</author>
<namespace>meera</namespace>
<entity name="Student" local-service="true"
remote-service="true">
<column name="studentId" type="long" primary="true"
/>
<column name="studentName" type="String" />
<column name="studentAddress" type="String" />
</entity>
</service-builder>
|
Now run service builder once run service builder
successfully then you can get Student-portlet-service.jar
in WEB-INF/lib
Now we have to copy Student-portlet-service.jar file to liferay global lib
If
Tomcat
tomcat-7.0.27\lib\ext
|
If JBoss
jboss-7.1.1\modules\com\liferay\portal\main
Register
jar file name in module.xml as follows
<resource-root
path=" Student-portlet-service.jar" />
|
Remove Student-portlet-service.jar
file form portlet WEB-INF/lib directory
Now deploy then portlet and portlet should be
successfully deployed.
Now use following code in portal_normal.vm of your
currently working theme
#set
($studentLocalService= $serviceLocator.findService("com.liferay.portal.service.UserLocalService"))
#set
($student = $studentLocalService.getStudent(1)
#set
($studentName= $student.getStudentName())
<div>Hi
I am student my name is <h1>($studentName</h1></div>
|
Note:
When we use plugin portlet services in then we have
to apply above steps to each change/modification in plug-in portlet services .so make sure you
have to follow the steps properly for each change.
Important
points
- Liferay provide many velocity variables to use in themes.
- Service locater is one velocity variable in liferay from that we can get any services from liferay.
- To access service in liferay all services should be in Liferay Global class path.
Reference
Links:
https://www.liferay.com/community/wiki/-/wiki/Main/Access+to+Liferay+services+in+Velocity
https://www.liferay.com/ja/community/forums/-/message_boards/message/13172256
https://www.liferay.com/ja/community/forums/-/message_boards/message/13172256
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