Applications in Java

Drawer PDF417 in Java Applications
Applications
PDF 417 Maker In Java
Using Barcode printer for Java Control to generate, create PDF-417 2d barcode image in Java applications.
Services Services
Bar Code Generator In Java
Using Barcode maker for Java Control to generate, create barcode image in Java applications.
Applications
Barcode Scanner In Java
Using Barcode scanner for Java Control to read, scan read, scan image in Java applications.
APIs
PDF 417 Maker In Visual C#
Using Barcode creation for .NET Control to generate, create PDF 417 image in .NET framework applications.
Service Component Architecture
PDF 417 Generation In VS .NET
Using Barcode creator for ASP.NET Control to generate, create PDF417 image in ASP.NET applications.
Web Services Remote Binary Messaging Other Bindings
Painting PDF 417 In .NET Framework
Using Barcode printer for .NET framework Control to generate, create PDF-417 2d barcode image in Visual Studio .NET applications.
Windows Communications Foundation
Drawing PDF 417 In VB.NET
Using Barcode creation for .NET framework Control to generate, create PDF417 image in .NET applications.
Web Services Remote Binary MSMQ DCOM
Code 128 Generation In Java
Using Barcode generation for Java Control to generate, create Code 128B image in Java applications.
Protocols
Barcode Generator In Java
Using Barcode generation for Java Control to generate, create barcode image in Java applications.
SCA and NET architectures
Barcode Generation In Java
Using Barcode encoder for Java Control to generate, create bar code image in Java applications.
Adapted from David Chappell, wwwdavidchappellcom
Drawing EAN / UCC - 14 In Java
Using Barcode drawer for Java Control to generate, create EAN / UCC - 13 image in Java applications.
This uni ed approach simpli es development by eliminating the need for application logic to resort to specialized, low-level APIs
Encoding UPC-A Supplement 2 In Java
Using Barcode generation for Java Control to generate, create UPC-A Supplement 5 image in Java applications.
The second problem SCA addresses concerns reuse There are two basic types of code reuse: within the same process (intra-process reuse) and across processes (inter-process reuse) Object-oriented programming languages introduced innovative features, including interfaces, classes, polymorphism, and inheritance that enabled applications to be decomposed into smaller units within the same process By structuring applications in terms of classes, objectoriented code could be more easily accessed, reused, and managed than code written with procedural programming languages
Codabar Creator In Java
Using Barcode printer for Java Control to generate, create Code-27 image in Java applications.
Introducing SCA
Bar Code Creator In C#.NET
Using Barcode printer for Visual Studio .NET Control to generate, create barcode image in .NET framework applications.
In the 1990s, distributed object technologies such as DCE, DCOM, CORBA, and EJB attempted to apply these same principles of reuse to applications spread across multiple processes After numerous iterations, the industry learned from distributed object technologies that the principles of object-oriented design do not cleanly apply across remote boundaries Distributed object technologies often resulted in application architectures that tightly coupled clients to service providers This coupling made systems extremely fragile Updating applications with a new version of a service provider frequently resulted in client incompatibilities Moreover, these technologies failed to adequately address key differences in remote communications such as network latency, often leading to poor system performance
Data Matrix Creator In Visual Basic .NET
Using Barcode creator for VS .NET Control to generate, create DataMatrix image in .NET applications.
SCA provides a way to assemble, manage, and control distributed systems
Scan EAN / UCC - 13 In VS .NET
Using Barcode recognizer for .NET framework Control to read, scan read, scan image in .NET framework applications.
However, despite the shortcomings of distributed objects, the idea behind inter-process reuse is still valid: There is far greater value in code that is organized into reusable units and accessible to multiple clients running in different processes As we will explain in more detail, SCA provides a foundation for application resources and logic to be shared by multiple clients that builds on the lessons learned from distributed objects Similar to the way object-oriented languages provide mechanisms for organizing and reusing inprocess application logic, SCA provides a way to assemble, manage, and control distributed systems In order to achieve reuse, SCA de nes services, components, and composites In SCA, applications are organized into components that offer functionality to clients (typically other components) through services Services may be reused by multiple clients Components in turn may rely on other services As we will see, SCA provides a mechanism to connect or wire components to these services This is done through a composite, which is an XML le Figure 13 shows a typical SCA application
Painting Barcode In C#
Using Barcode drawer for .NET Control to generate, create bar code image in .NET applications.
Composite Components
Barcode Decoder In Java
Using Barcode decoder for Java Control to read, scan read, scan image in Java applications.
In SCA, applications are organized into components that offer functionality to clients through services
UPC A Decoder In .NET
Using Barcode decoder for VS .NET Control to read, scan read, scan image in .NET framework applications.
Service
Generating EAN128 In VS .NET
Using Barcode printer for ASP.NET Control to generate, create UCC-128 image in ASP.NET applications.
An SCA application
SCA and Enterprise Architectures
SCA and Enterprise Architectures
Unlike Java EE and NET, SCA is not intended to be an allencompassing technology platform SCA does not specify mechanisms to persist data or a presentation-tier technology for building user interfaces Rather, SCA integrates with other enterprise technologies such as JDBC and Java Persistence Architecture (JPA) for storing data in a database and the myriad of web-based UI frameworks that exist today (servlets and JSP, Struts, JavaServer Faces [JSFs], and Spring WebFlow, to name a few) Figure 14 illustrates a typical SCA architecture, which includes the use of presentation and persistence technologies
Persistence JDBC/JPA, etc SCA Services
SCA does not specify mechanisms to persist data or a presentation-tier technology for building user interfaces
Composite
Presentation Tier
Composite Remote Service Clients
Using persistence and presentation technologies with SCA
In 10, Service-Based Development Using BPEL, and 11, Persistence, we take a closer look at using SCA with some of the more popular persistence and presentation technologies
Introducing SCA
Perspective: A New Way to Standards
Today, SCA is a set of OASIS standards according to the of cial processes and procedures laid out by that organization Prior to OASIS, from November 2005 to March 2007, SCA work was done as part of a collaboration of vendors, termed Open SOA or OSOA (wwwosoaorg) One of the primary reasons for doing this work outside of an of cial standards organization was the immaturity of SCA and time-to-market: Standards organizations are bureaucratic and their processes slow things down This is not necessarily a bad thing, particularly for mature technologies on which many businesses must rely for years In these cases, stability is an overriding concern SCA, in contrast, was a new technology in a rapidly evolving market Consequently, the collaboration participants needed the ability to make changes relatively quickly, changes that would at times break compatibility with previous versions of the speci cations Even a cursory comparison of the 09 version of the speci cations published in November 2005 with the 10 version in March 2007 quickly reveals signi cant new features and areas that underwent substantial modi cation In hindsight, this was arguably the correct approach to take One of the notable aspects of this process is that it diverged from the path taken by many previous speci cations, in particular Java EE and CORBA, which were largely designed by of cial standards committees In this respect, SCA shares more in common with how web services standards began: as informal vendor collaborations prior to being submitted to an of cial standards organization Given that both web services and SCA efforts have taken the approach of using a collaboration model prior to standardization, the industry may be witnessing a shift in how technology speci cations are developed Although there are certainly upsides to this approach in terms of faster iteration, there are some potentially negative consequences One of those potential negative consequences is the smoke- lled room scenario, where a few vendors conspire to create speci cations that do not take into account real user requirements We will need to wait and see whether this collaborative approach becomes the modus operandi for new technology development and whether it represents an improvement over speci cations developed entirely within a standards body