Create a simple JSR 286 Portlet - Part 2

In the last article we had completed the setup.


Now we will create our first JSR 286 Portlet.

1. In Eclipse navigate and go to File->new->other.

2. Type Maven.

3. Next type web and select maven-archetype-webapp
4. Type FirstPortlet next

5. Update your pom.xml file to add the following dependencies:

<dependencies>
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>servlet-api</artifactId>
            <version>2.5</version>
        </dependency>
        <dependency>
            <groupId>javax.portlet</groupId>
            <artifactId>portlet-api</artifactId>
            <version>2.0</version>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>jstl</artifactId>
            <version>1.1.1</version>
        </dependency>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>3.8.1</version>
            <scope>test</scope>
        </dependency>
    </dependencies>

If you are only interested in the Portlet you can skip the section below and directly go to the Portlet creation section. Below I have demonstrated how a simple servlet can be created and deployed in the tomcat bundle.

Sample Servlet:

In the Portlet Application open the web.xml file. Its located in /webapps/WEB-INF/web.xml :

Add/Update the following.

<servlet>
    <servlet-name>SampleServlet</servlet-name>
    <servlet-class>com.code.servlets.SampleServlet</servlet-class>
</servlet>
<servlet-mapping>
    <servlet-name>SampleServlet</servlet-name>
    <url-pattern>/testservlet/*</url-pattern>
</servlet-mapping>
<servlet-mapping>
    <servlet-name>SampleServlet</servlet-name>
    <url-pattern>/testservlet</url-pattern>
</servlet-mapping>

2. Create the Servlet class

Create a new package com.code.servlets in the main/java folder.
Your package hierarchy should look like the one below

Create a new class in this package. Call it SampleServlet.java


Create a Servlet class to handle the request Refer to the code below:

package com.code.servlets;

import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public class SampleServlet extends HttpServlet{

    private static final long serialVersionUID = 1L;
   
    public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException{
        request.getRequestDispatcher("/WEB-INF/jsp/home.jsp").forward(request, response);
    }

}

Also create a JSP file home.jsp with some welcome message. This completes the sample Servlet.


Create the Portlet


Now we create the Portlet. Here is the Portlet class MainControllerwhich extends GenericPortlet.

package com.code.controller;

import java.io.IOException;

import javax.portlet.GenericPortlet;
import javax.portlet.PortletException;
import javax.portlet.PortletRequest;
import javax.portlet.PortletResponse;
import javax.portlet.RenderMode;

public class MainController extends GenericPortlet{
    /*Using Annotation for invoking the render method for View mode*/
    @RenderMode(name = "view")
    public void render(PortletRequest request, PortletResponse response) throws PortletException, IOException{
        getPortletContext().getRequestDispatcher("/WEB-INF/jsp/main.jsp").include(request, response);
    }
}

Also create a main.jsp file which is a simple JSP with some welcome message.


We will need three XML files. The main one is portlet.xml file which identifies an application as a Portlet Application.

Below is the portlet.xml I have used for this application

<portlet>
    <portlet-name>FirstPortlet</portlet-name>
    <portlet-class>com.code.controller.MainController</portlet-class>
    <init-param>
        <name>owner</name>
        <value>Ankur</value>
    </init-param>
    <expiration-cache>60</expiration-cache>
    <cache-scope>private</cache-scope>
    <supports>
        <mime-type>text/html</mime-type>
        <portlet-mode>view</portlet-mode>
        <portlet-mode>edit</portlet-mode>
        <portlet-mode>print</portlet-mode>
        <portlet-mode>help</portlet-mode>
        <window-state>pop_up</window-state>
    </supports>
    <resource-bundle>Language-ext</resource-bundle>
</portlet>

We also need two more XML files which are specific to Liferay.

liferay-portlet.xml, liferay-display.xml


We are all set to deploy and test our first application.

Build and Deploy:

• If you have the Eclipse Maven plugin then you can build this application from Eclipse itself.
• Just right click go to Run As -> Maven Build. In the Goals box enter clean install.
• Go to JRE tab and select the alternate JRE, the custom JDK on your machine.
• Click on Run. Maven will create the war file which can be hot deployed to Liferay server.
• Just refresh your project once build is complete and copy the war from target folder.
• Place this in the deploy folder of your Liferay bundle.

Now start the server.

Sign in to the Portal using test@liferay.com / test and then add a new Page. On this page add the FirstPortlet Portlet.

You can test the servlet by going to: http://localhost:8080/FirstPortlet/testservlet