|By David Bismut, Krishnakumar Pooloth, Swaminathan Natarajan||
|July 31, 2005 07:00 PM EDT||
Property files are frequently used in systems built using Java whether it's a thick Java client, a servlet, or a business component. Java specifies the format for a property file and provides the Properties class to read from and write to these files. However, Java is silent on the aspects related to validations of a value entered in a property file, providing room for errors to creep into an application system. How many times have you started to debug a failure in an application only to realize that it's because of an incorrect value in a property file?
The Properties Editor Framework detailed in this article was developed to solve the problem of managing application properties. It provides a convenient way to define a data type for each property and have a companion component in Swing to edit the property value. The framework can be used as a standalone tool or as part of a user interface.
One of the framework's design criteria was that it should work out of a property file, i.e., no other files or databases should be required for managing the property file. This is achieved by using certain meta-attributes to describe the characteristics of each property in the properties file. These meta-attributes are embedded along with each property in the property file as comments (Any line, in a property file, starting with '#' is considered a comment in Java).
In this article, we'll describe the framework's use, the concept of meta-attributes, and the default set of the attributes supported by the framework. And then, we'll explain the framework's design and how to extend it to support a new property data type.
Using the Property Editor Framework
The first step in using the Property Editor Framework is to decide on the Parameter type of each property in the properties file. Currently the framework supports the types listed in Table 1.
The next step is to modify the properties file and add the necessary meta-attributes for each property. Listing 1 shows a sample properties file with meta-attributes.
The final step is to set up the environment for the Property Editor Framework and invoke the Property Editor Dialog to start updating the property values. Figure 1 shows the properties as rendered in the Property editor Dialog.
The basic meta-attributes speci-fied by the framework for each property are Parameter Type, Editable, and Documentation. The Parameter Type represents the type of a property. It's used to render a suitable component for editing the property value. The table below lists the components rendered for the each of the possible values of PARAMETER TYPE.
The meta-attribute EDITABLE indicates whether the user can edit the value of a property. In the Property Editor Dialog, only properties that have a true value for EDITABLE meta-attribute are displayed. This lets the application developer make certain attributes in a property file not editable through the dialog.
The DOCUMENTATION meta-attribute specifies the text (which can be specified using HTML) that provides assistance to the end user while editing any particular property. In Figure 1, this documentation is displayed below the JTable con-taining the editable properties. As HTML tags are accepted, the <A> anchor tag can be used to provide a link to more comprehensive documentation.
Apart from the basic meta-attributes, there are two special meta-attributes. First one, GROUP NAME, is used to group related properties together. In the Property Editor Dialog, each property group is displayed in a separate tab. This could be used to group your attributes into, say, 'Basic' and 'Advanced.' Note that this parameter shouldn't be specified for each property separately. Once a GROUP NAME tag appears, all the parameters till the next GROUP NAME tag are grouped together. Another special meta-attribute is ALLOWED VALUES, which is used in conjunction with the SYMBOL parameter type. This lets you specify the list of valid choices for a SYMBOL property. These values should be separated by commas.
Now that we have a good idea about meta-attributes, let's walk through the steps in adding them to the Property File. Consider the following set of Properties.
Step 1: Decide the Grouping of the Properties
In the example the properties can be split into two groups based on their purpose, Logging and Database connection. Let's call these groups Logging and Database.
#GROUPNAME = Database
# GROUPNAME = Logging
Step 2: Decide on the Type for Each Property
In the example above, the types to be assigned to each property are shown in Table 3.
Step 3: Add Meta-Attributes to Each Property
The complete listing of this sample is available for download along with the source (see Listing 2).
Design of the Property Editor Framework
In this section, we will detail the design of the Properties Editor Framework. To reduce complexity, we'll break the discussion into: Creating the model of the Properties Editor component, creating the UI of the Properties Editor component, and the framework's persistence mechanism for the properties file.
Creating the Model
The classes involved in reading the properties file into memory and creating the data model are depicted in Figure 2.
The EditorFile class, which ex-tends the File class, is used as a thin wrapper for the Properties file. The EditorFile class provides the facility to add an Observer, which will be notified when changes are made to the property values.
The Parser class is a simple line parser that reads data from the EditorFile instance line-by-line and creates an in-memory model of the property file. It also defines the regular expression patterns to match the different meta-attributes supported by the framework. This class creates a new instance of Group class each time the meta-attribute '#GROUP NAME = <Group Name>' is encountered.
For each property key-value that falls under the same #GROUP NAME, an instance of one of the sub-classes of the Parameter class hierarchy is created. The exact sub-class is decided by the value of the meta-attribute #PARAMETER TYPE, which also keeps track of the value of meta-attribute EDITABLE that's used later by the view to decide whether to make it visible.
Creating the User Interface
The classes involved in rendering the user interface of the component are depicted Figure 3.
Referring to Figure 1, the visual area of the dialog is split between the Panel used to render the table of property key-value pairs and the JEditorPane showing the documentation text of different properties.
|Java Developer's Journal 07/31/05 06:42:09 PM EDT|
Enterprise Java - Properties Editor Framework
In his keynote at 18th Cloud Expo, Andrew Keys, Co-Founder of ConsenSys Enterprise, provided an overview of the evolution of the Internet and the Database and the future of their combination – the Blockchain. Andrew Keys is Co-Founder of ConsenSys Enterprise. He comes to ConsenSys Enterprise with capital markets, technology and entrepreneurial experience. Previously, he worked for UBS investment bank in equities analysis. Later, he was responsible for the creation and distribution of life sett...
Sep. 26, 2016 01:15 PM EDT Reads: 3,277
The many IoT deployments around the world are busy integrating smart devices and sensors into their enterprise IT infrastructures. Yet all of this technology – and there are an amazing number of choices – is of no use without the software to gather, communicate, and analyze the new data flows. Without software, there is no IT. In this power panel at @ThingsExpo, moderated by Conference Chair Roger Strukhoff, panelists will look at the protocols that communicate data and the emerging data analy...
Sep. 26, 2016 01:00 PM EDT Reads: 1,603
DevOps at Cloud Expo, taking place Nov 1-3, 2016, at the Santa Clara Convention Center in Santa Clara, CA, is co-located with 19th Cloud Expo and will feature technical sessions from a rock star conference faculty and the leading industry players in the world. The widespread success of cloud computing is driving the DevOps revolution in enterprise IT. Now as never before, development teams must communicate and collaborate in a dynamic, 24/7/365 environment. There is no time to wait for long dev...
Sep. 26, 2016 12:45 PM EDT Reads: 3,408
SYS-CON Events announced today that China Unicom will exhibit at the 19th International Cloud Expo, which will take place on November 1–3, 2016, at the Santa Clara Convention Center in Santa Clara, CA. China United Network Communications Group Co. Ltd ("China Unicom") was officially established in 2009 on the basis of the merger of former China Netcom and former China Unicom. China Unicom mainly operates a full range of telecommunications services including mobile broadband (GSM, WCDMA, LTE F...
Sep. 26, 2016 12:45 PM EDT Reads: 1,729
Fifty billion connected devices and still no winning protocols standards. HTTP, WebSockets, MQTT, and CoAP seem to be leading in the IoT protocol race at the moment but many more protocols are getting introduced on a regular basis. Each protocol has its pros and cons depending on the nature of the communications. Does there really need to be only one protocol to rule them all? Of course not. In his session at @ThingsExpo, Chris Matthieu, co-founder and CTO of Octoblu, walk you through how Oct...
Sep. 26, 2016 12:45 PM EDT Reads: 2,030
Data is an unusual currency; it is not restricted by the same transactional limitations as money or people. In fact, the more that you leverage your data across multiple business use cases, the more valuable it becomes to the organization. And the same can be said about the organization’s analytics. In his session at 19th Cloud Expo, Bill Schmarzo, CTO for the Big Data Practice at EMC, will introduce a methodology for capturing, enriching and sharing data (and analytics) across the organizati...
Sep. 26, 2016 12:15 PM EDT Reads: 1,664
SYS-CON Events announced today that ReadyTalk, a leading provider of online conferencing and webinar services, has been named Vendor Presentation Sponsor at the 19th International Cloud Expo, which will take place on November 1–3, 2016, at the Santa Clara Convention Center in Santa Clara, CA. ReadyTalk delivers audio and web conferencing services that inspire collaboration and enable the Future of Work for today’s increasingly digital and mobile workforce. By combining intuitive, innovative tec...
Sep. 26, 2016 12:00 PM EDT Reads: 2,783
The Transparent Cloud-computing Consortium (abbreviation: T-Cloud Consortium) will conduct research activities into changes in the computing model as a result of collaboration between "device" and "cloud" and the creation of new value and markets through organic data processing High speed and high quality networks, and dramatic improvements in computer processing capabilities, have greatly changed the nature of applications and made the storing and processing of data on the network commonplace.
Sep. 26, 2016 11:30 AM EDT Reads: 991
SYS-CON Events announced today that Commvault, a global leader in enterprise data protection and information management, has been named “Bronze Sponsor” of SYS-CON's 19th International Cloud Expo, which will take place on November 1–3, 2016, at the Santa Clara Convention Center in Santa Clara, CA. Commvault is a leading provider of data protection and information management solutions, helping companies worldwide activate their data to drive more value and business insight and to transform moder...
Sep. 26, 2016 11:30 AM EDT Reads: 2,572
There is little doubt that Big Data solutions will have an increasing role in the Enterprise IT mainstream over time. Big Data at Cloud Expo - to be held November 1-3, 2016, at the Santa Clara Convention Center in Santa Clara, CA - has announced its Call for Papers is open. Cloud computing is being adopted in one form or another by 94% of enterprises today. Tens of billions of new devices are being connected to The Internet of Things. And Big Data is driving this bus. An exponential increase is...
Sep. 26, 2016 11:30 AM EDT Reads: 2,537
SYS-CON Events announced today the Enterprise IoT Bootcamp, being held November 1-2, 2016, in conjunction with 19th Cloud Expo | @ThingsExpo at the Santa Clara Convention Center in Santa Clara, CA. Combined with real-world scenarios and use cases, the Enterprise IoT Bootcamp is not just based on presentations but with hands-on demos and detailed walkthroughs. We will introduce you to a variety of real world use cases prototyped using Arduino, Raspberry Pi, BeagleBone, Spark, and Intel Edison. Y...
Sep. 26, 2016 11:15 AM EDT Reads: 2,865
Major trends and emerging technologies – from virtual reality and IoT, to Big Data and algorithms – are helping organizations innovate in the digital era. However, to create real business value, IT must think beyond the ‘what’ of digital transformation to the ‘how’ to harness emerging trends, innovation and disruption. Architecture is the key that underpins and ties all these efforts together. In the digital age, it’s important to invest in architecture, extend the enterprise footprint to the cl...
Sep. 26, 2016 11:06 AM EDT Reads: 156
Video experiences should be unique and exciting! But that doesn’t mean you need to patch all the pieces yourself. Users demand rich and engaging experiences and new ways to connect with you. But creating robust video applications at scale can be complicated, time-consuming and expensive. In his session at @ThingsExpo, Zohar Babin, Vice President of Platform, Ecosystem and Community at Kaltura, will discuss how VPaaS enables you to move fast, creating scalable video experiences that reach your...
Sep. 26, 2016 11:00 AM EDT Reads: 989
SYS-CON Events announced today that SoftLayer, an IBM Company, has been named “Gold Sponsor” of SYS-CON's 18th Cloud Expo, which will take place on June 7-9, 2016, at the Javits Center in New York, New York. SoftLayer, an IBM Company, provides cloud infrastructure as a service from a growing number of data centers and network points of presence around the world. SoftLayer’s customers range from Web startups to global enterprises.
Sep. 26, 2016 10:30 AM EDT Reads: 893
SYS-CON Events announced today that Bsquare has been named “Silver Sponsor” of SYS-CON's @ThingsExpo, which will take place on November 1–3, 2016, at the Santa Clara Convention Center in Santa Clara, CA. For more than two decades, Bsquare has helped its customers extract business value from a broad array of physical assets by making them intelligent, connecting them, and using the data they generate to optimize business processes.
Sep. 26, 2016 10:00 AM EDT Reads: 2,689
Big Data has been changing the world. IoT fuels the further transformation recently. How are Big Data and IoT related? In his session at @BigDataExpo, Tony Shan, a renowned visionary and thought leader, will explore the interplay of Big Data and IoT. He will anatomize Big Data and IoT separately in terms of what, which, why, where, when, who, how and how much. He will then analyze the relationship between IoT and Big Data, specifically the drilldown of how the 4Vs of Big Data (Volume, Variety,...
Sep. 26, 2016 10:00 AM EDT Reads: 1,003
Cognitive Computing is becoming the foundation for a new generation of solutions that have the potential to transform business. Unlike traditional approaches to building solutions, a cognitive computing approach allows the data to help determine the way applications are designed. This contrasts with conventional software development that begins with defining logic based on the current way a business operates. In her session at 18th Cloud Expo, Judith S. Hurwitz, President and CEO of Hurwitz & ...
Sep. 26, 2016 09:45 AM EDT Reads: 2,864
WebRTC adoption has generated a wave of creative uses of communications and collaboration through websites, sales apps, customer care and business applications. As WebRTC has become more mainstream it has evolved to use cases beyond the original peer-to-peer case, which has led to a repeating requirement for interoperability with existing infrastructures. In his session at @ThingsExpo, Graham Holt, Executive Vice President of Daitan Group, will cover implementation examples that have enabled ea...
Sep. 26, 2016 09:00 AM EDT Reads: 1,529
The vision of a connected smart home is becoming reality with the application of integrated wireless technologies in devices and appliances. The use of standardized and TCP/IP networked wireless technologies in line-powered and battery operated sensors and controls has led to the adoption of radios in the 2.4GHz band, including Wi-Fi, BT/BLE and 802.15.4 applied ZigBee and Thread. This is driving the need for robust wireless coexistence for multiple radios to ensure throughput performance and th...
Sep. 26, 2016 08:15 AM EDT Reads: 1,545
Vidyo, Inc., has joined the Alliance for Open Media. The Alliance for Open Media is a non-profit organization working to define and develop media technologies that address the need for an open standard for video compression and delivery over the web. As a member of the Alliance, Vidyo will collaborate with industry leaders in pursuit of an open and royalty-free AOMedia Video codec, AV1. Vidyo’s contributions to the organization will bring to bear its long history of expertise in codec technolo...
Sep. 26, 2016 08:15 AM EDT Reads: 2,505