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Tuesday, 15 September 2009 09:32

J2EE Design Patterns: The Business Tier

The Business Tier Business tiers are about complexity, memory, and scale. Business tiers are complex because they implement the rules the business must follow. The rules themselves can be simple ("mark each item shipped as removed from inventory," "when shipping to Massachusetts, add a 5% sales tax") but the interconnected system of rules can rapidly become more than any one person can easily handle. Memory, in the long-term recollection sense rather than the hardware sense, is important because businesses need to record every activity they participate in. Humans aren't well equipped to do this reliably, at least without tools and time. Finally, business tiers are about scale. Even if process and record-keeping activities are simple enough to be done by hand, repeating them several thousand times over the course of a day is costly, error-prone, and inflexible.[1] In the business tier, more than anywhere else, you have to keep an eye out for the unexpected. Creating domain models and business logic that meet the growth requirements of the environment presents a challenge to system architects. Even when the initial application requirements may not seem to impose much in terms of complexity, memory, and scale, change is inevitable. Business tiers require…
Thursday, 06 August 2009 12:38

Liferay Features

Liferay offers several benefits over similar frameworks in the market: • Ease of use • Support for a wide variety of applications • Liberal licensing and open source code • Extensibility • Scalability • Internationalization support • Integration with other tools • Adherence to industry standards Ease of Use Like the Yahoo! portal, portals created using Liferay are easy to use. You can add variousapplications to portal pages by using Liferay’s drag-and-drop feature, and you can move themaround by clicking and dragging. You can remove an existing application from the page with asingle click on the close icon, and you can easily change the page layout by applying a differentpage template. You can also change the look and feel of a page by applying a theme providedby Liferay or third parties. So you can create a portal easily and allow the user to configure it asdesired. You can take advantage of all these features without writing a single line of code. Support for a Wide Variety of Applications Liferay provides a wide range of applications or portlets that you can use, including wikis,blogs, chat, and discussion forums, to name a few. In addition to these, you can incorporateapplications made available…
Wednesday, 19 August 2009 09:58

Doing Portal Administration

Using the Admin Portlet Liferay provides a useful application called Admin that helps you perform several administrative tasks. Such tasks involve monitoring resource utilization to ensure optimal portal performance, logging messages from various classes in the system to get insight into what’s happening under the hood, checking the various system and portal properties, monitoring server instances, shutting down the server, and so on. You will now learn to use the Admin portlet. First, you need to install this portlet on your ISI portal. For this, you will create a private page in your own community. Users without administrator privileges will not be able to use the portlet, but it’s still a good idea to put it on a private page rather than a public page. Perform these steps to create a private page: 325 1. Log on to the portal using your Administrator account. 2. Open the drop-down Welcome menu. 3. Navigate to the Private Pages menu item of the Fundamental Analysts community that you created previously 4. Click the new-page icon on the right side of the menu item This opens the Manage Pages screen, which lets you create a new page 5. Enter Administration as the page name.…
Configuring the Journal Application Now we will study the configuration settings for the Journal portlet at the application level. When you click the application-configuration icon, you will see four tabbed options:   • Setup: Lets you set various e‑mail formats • Permissions: Lets you set permissions for different user roles • Export/Import: Facilitates the export and import of data • Sharing: Facilitates application sharing Setup Under the Setup option , you can set up the formats for various e‑mail messages, such as these:   • Email From • Article Denied Email • Article Granted Email • Article Requested Email • Article Review Email   Email From In the Email From tabbed option, you can set the sender information for all the applicationgenerated e‑mail messages. In particular, you enter the sender’s name and e‑mail ID. Article Denied Email The Article Denied Email tab allows you to set the format for the e‑mail message that communicates an article rejection. If you decide to reject an article because its contents are unsuitable, the application sends an automated message to the author using the format specified on this screen (see Figure 10-24). The message format uses several predefined fields, which are listed at the…
Tuesday, 18 August 2009 13:09

Managing Content

  Implementing Document Management First, we will consider text-based documents in various formats, such as PDFs, Word documents, spreadsheets, and so on. For managing such documents, Liferay provides two important applications: • Document Library • Document Library Display You will now study the use of these applications, starting with Document Library. The Document Library application allows you to organize and manage your documents. You use it to create a tree-structured hierarchy where the documents are published and stored. Thus, you can organize the document storage logically so that users can easily locate the files. Adding the Application To add the Document Library application on our ISI portal page, follow the steps listed here:   1. Log in as Administrator on the ISI portal. 2. Create a new page called Document Library under our predefined communities, or at any other location you’d like. 3. Select the Add Application menu. 4. Select and add the Document Library application from the CMS category.   Now you’re ready to create a folder structure for document storage. You’ll create a hierarchy of folders for storing documents created by our analysts and categorize the documents into two types: • Fundamental Analysis Documents • Technical Analysis Documents…
Installing the Calendar Application   To install the Calendar application on your portal, follow these steps:   1. Log in to the portal using your administrator account.   2. Create a new public page called Shared Calendar under either the Fundamental or Technical community. Or you could create a general page that’s accessible to both groups.   3. Select the Add Application menu item.   4. Open the Collaboration category and click the Add link associated with the Calendar application   Setting Up Events Adding an Event To set up an event, follow these steps:   1. View the Calendar application, which initially shows the calendar for the current system date   2. Select the date on which you want to set the event.   3. Click the Add Event button. You will see the screen shown in Figure 8-3.     4. Select the date and time for the event.   5. Select the event duration by selecting hours and minutes from the two displayed dropdown boxes. If it is an all-day event, check the corresponding check box.   6. If your event is conducted at a location that abides by Daylight Saving Time, check the Time Zone Sensitive…
Tuesday, 18 August 2009 16:45

Publishing Dynamic Content

Installing the Journal Application The application that we are going to use for creating regularly changing content is called the Journal portlet. First, you need to install this application on the ISI portal. Follow these steps to perform the installation:   1. Log on to the ISI portal using your Administrator account. 2. Create a public page called Dynamic under one of our communities, or at any other location of your choice. 3. Select the Add Application menu. 4. Locate the Journal application under the CMS category. 5. Add the application to the page. Creating Article Structures To create a new journal-article structure, follow these steps:   1. Click the Structures tab in the main application window of the Journal portlet. The screen shows a list of available structures. As no structures are currently defined, this list is blank. 2. Click the Add Structure button to create a new structure. 3. Take these actions on this screen: a. Autogenerate ID: Each structure has its own unique ID. If you do not wish to track your own IDs, allow the application to autogenerate the IDs by marking this check box. b. Name: Enter Announcement Structure. c. Description: Enter This defines the…
Tuesday, 18 August 2009 09:50

Setting Wiki Application-level Properties

Setting Application Properties To set the application-level properties, return to full-application view if you are still within the application. Click the Configuration button on the top-right corner of the screen. You will see the following tabbed options: • Setup   • Permissions   • Export/Import   • Sharing Setup When you select the configuration option in the application menu, the first tab that you see is the Setup tab  Here, you will see the five tabbed options for setup:  • Email From    • Page Added Email    • Page Updated Email    • Display Settings    • RSS  Email From The Email From option allows you to set the sender information for messages that the application sends to an outsider. Usually, the application will send automatic mail notifications to its e‑mail subscribers whenever a new page is added or updated on the wiki. As Figure 7-26 shows, this screen accepts the Name and Address of the sender. After entering this information, you can save your changes by clicking the Save button. The mail notifications will now carry this sender information in each message.  Page Added Email The Page Added Email option asks you to enter the subject, body, and…
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