Hello World - WebSphere Portal V5 The simplest portal: Part 2, rendering JSP

This article will learn how to develop and deploy a portlet-based simple JSP in IBM WebSphere Portal Version 5.

Introduction In the first article of the "Hello World" sequence, you have already learned how to create a portlet in Java, which can output "Hello, World". This is exemplary, not a practical method for developing portlets. So, what kind of problem is it? This article (second article) solves one of the problems in the future.

In this simplest "Hello World!" Program, the Java code contains text "Hello, World", and also contains logic that displays this text. If you can separate the portlet's logic and the part of the logic, the program will do better because this allows you to create a portlet that supports different dollars and different national languages. Today, you may not need to create a portlet for wireless tag language (Wireless Markup Language, WML), or do not need to create a German version of Portlet. But what about tomorrow?

You may also work with a graphic designer, and he frequently changes the appearance and feel. If the presentation part is done in the Java code, a developer and a editorial processor need to be modified. The way to solve this problem is to use JSP to present your portlet, which allows you to create a separate JSP file, each file supporting a metadata or a national language. Designers can fully control JSP and make changes to it, and no longer need to assist in developers.

In this article, you will see how to build a portlet in IBM® WebSphere® Portal Version 5, which calls a JSP to present it in it. Then we will introduce this JSP and some tags from the portlet tag library. Finally, create a deployment descriptor and put all these things into a package and deploy it into the portal.

Creating a directory structure First, you must create a directory structure where your portlet can be stored. The following is that you will be used in the portlet:

HelloWorld / COM / IBM / Portlets / Sample - The location of the source code is stored. HelloWorld / Web-INF - Stores the location of the deployment descriptor. HelloWorld / Web-INF / LIB - The location of the JAR file is stored. HelloWorld / JSP - Stores the location of the JSP file.

Important: All directory and environmental references are based on Windows practices. You can do some corresponding adjustments to make it suitable for UNIX systems.

Creating a Java Code Sample Directory is where you store the Java source file. Create a file called HelloWorld.java in this directory and open it with your favorite text editor. Below you need to type it (or cut and paste into) the HelloWorld.java file created:

Package com.ibm.portlets.sample;

// portlet APIT

Import org.apache.jetspeed.portlet. *;

// java stuff

Import java.io. *;

Public class helloworld extends portletadapter {

Public Void Service (PortletRequest Request, PortletResponse Response)

Throws portletException, IOEXCEPTION {

// incrude the view jsp

GetPortletConfig (). getContext (). include ("/jsp/view.jsp",

REQUEST, RESPONSE;

}

}

After the code creates a source file, you can compile the Java code. You can use the following scripts to compile this portlet in a batch file. First define some environment variables, such as defining the environment variables of the Java installation location (java_home). Compiling the JDK provided by WebSphere Application Server is usually a good idea because this is the environment you want to run.

You also need to set the PATH environment variable to include the installation location of the Java compiler. Also set the libpath variable to point to the directory where the WebSphere JAR file is located.

Next, design a variable called CP for our compile class path. The CP variable can be built on a row, but in order to illustrate the different JAR files required, we disassemble the branch display. Then call the Java compiler to compile the code. The code assumes that you are in the HelloWorld directory. Adjust the directory path to the path to your installation.

Set java_home = c: / WebSphere / AppserVer / Java

SET PATH =% java_home% / bin

SET LIBPATH = C: / WebSphere / AppServer / LIB

SET CP =.

SET CP =% CP%;% libpath% / j2ee.jar

SET CP =% CP%;% libpath% / Dynacache.jar

SET CP =% CP%; c: /websphere/portalser/shared/app/portlet-api.jar

Javac-ClassPath% CP% COM / IBM / Portlets / Sample / HelloWorld.java

If this is not compiled because some reason, you must correct the error before proceeding. Some common mistakes are:

Enter an error - class name, path, and variable name input error. File Name Error - File Name must match the class name. In our example, the file name is HelloWorld.java, and the class name is HelloWorld. If you have changed a name, another name must also change. Editor Error - Determines the editor to store files as text. An editor like a writing panel does not store the file to be stored as text.

Creating a JAR file After completing the compilation of the Java source file, you need to create a JAR file in a web-inf / lib directory. It is assumed that you are located in the HelloWorld directory. These statements can be included as part of the batch file you created above. This depends on the PATH set to point to the JAR program.

Set java_home = c: / WebSphere / AppserVer / Java

SET PATH =% java_home% / bin

Jar -cv0f ./web-inf/lib/helloworldfromjsp.jar COM / IBM / Portlets / Sample / *. Class

After creating a JSP file, you can concentrate on creating a JSP file after the JSP file is compiled. The JSP directory is where the JSP source file is stored. Create a file called View.jsp in this JSP directory and open it with your favorite text editor. Here is some JSP code, you need to type them (or cut and paste into the view.jsp file:

Hello World from the JSP!

It's that simple. Now you can pack them and run! After that, you can look back at this JSP and see what you can add to support different national languages ​​and different meta languages. Create a deployment descriptor now, you need to create two XML files:

HelloWorld / Web-INF / Web.xml - Web Deployment Descriptor. HelloWorld / Web-INF / portlet.xml - portlet deployment descriptor.

Web.xml - Web Deployment Descriptor Web Deployment Descriptor is required for WebSphere Portal. Now the portlet extends servlet, so you need to use the web deployment descriptor to declare the Servlet (portlet) class.

Application 2.3 // en "

"http://java.sun.com/j2ee/dtds/web-app_2_3.dtd">

HelloWorldFromjspportlet

HelloWorldFromJsp

com.ibm.portsets.sample.HelloWorld

HelloWorldFromJsp

/ helloworldfromjsp / *

Portlet.xml - Portlet Deployment Descriptor Portlet Deployment Descriptor defines portlets to the portal. Each portlet is mapped to a servlet defined in the web deployment descriptor through the HREF property of the portlet element. These references are represented by bold. Portlets must define a unique ID, each of which can reference the ID. Each specific portlet uses the given ID of the HREF attribute of the concrete-portlet element to reference the portlet. Take these references in blue.

1.1 // en "" portlet_1.1.dtd ">

Minor-version = "0"> HelloWorldFromJSP0Portlet

Minor-version = "0">

HelloWorldFromJsp

0

no

concrete helloworldfromjsp

author

tcat@us.ibm.com

HelloWorldFromJsp

en