Java Programming Language

The Java Programming Language The Java programming language is a high-level language that can be characterized by all of the following buzzwords: Simple Object oriented Distributed Multithreaded Dynamic

Architecture neutral Portable High performance Robust Secure

In the Java programming language, all source code is first written in plain text files ending with the .java extension. Those source files are then compiled into .class files by the Java compiler (javac). A .class file does not contain code that is native to your processor; it instead contains bytecodes-the machine language of the Java Virtual Machine. The Java launcher tool (java) then runs your application with an instance of the Java Virtual Machine.

Because the Java Virtual Machine is available on many different operating systems, the same .class files are capable of running on Microsoft Windows, the Solaris TM Operating System (Solaris OS), Linux, or MacOS..

The Java Platform A platform is the hardware or software environment in which a program runs. We've already mentioned some of the most popular platforms like Microsoft Windows, Linux, Solaris OS, and MacOS. Most platforms can be described as a combination of the operating system and underlying hardware. The Java platform differs from most other platforms in that it's a software-only platform that runs on top of other hardware-based platforms. The Java platform has two components: • •

The Java Virtual Machine The Java Application Programming Interface (API)

You've already been introduced to the Java Virtual Machine. It's the base for the Java platform and is ported onto various hardware-based platforms. The API is a large collection of ready-made software components that provide many useful capabilities, such as graphical user interface (GUI) widgets. It is grouped into libraries of related classes and interfaces; these libraries are known as packages.The following figure depicts how the API and the Java Virtual Machine insulate the program from the hardware.

As a platform-independent environment, the Java platform can be a bit slower than native code. However, advances in compiler and virtual machine technologies are bringing performance close to that of native code without threatening portability.

J 2 EE Java Platform, Enterprise Edition (Java EE) is the industry standard for developing portable, robust, scalable and secure server-side Java applications. Java Platform, Enterprise Edition (Java EE) is a set of coordinated technologies and practices that enable solutions for developing, deploying, and managing multi-tier, server-centric applications. Building on Java Platform, Standard Edition (Java SE), Java EE adds the capabilities that provide a complete, stable, secure, and fast Java platform for the enterprise. Java EE significantly reduces the cost and complexity of developing and deploying multi-tier solutions, resulting in services that can be rapidly deployed and easily enhanced.

The J2EE platform uses a distributed multitiered application model for enterprise applications. Application logic is divided into components according to function, and the various application components that make up a J2EE application are installed on different machines depending on the tier in the multitiered J2EE environment to which the application component belongs. Figure 1-1 shows two multitiered J2EE applications divided into the tiers described in the following list. The J2EE application parts shown in Figure 1-1 are presented in J2EE Components. • • • •

Client-tier components run on the client machine. Web-tier components run on the J2EE server. Business-tier components run on the J2EE server. Enterprise information system (EIS)-tier software runs on the EIS server.

Although a J2EE application can consist of the three or four tiers shown in Figure 1-1, J2EE multitiered applications are generally considered to be

three-tiered applications because they are distributed over three locations: client machines, the J2EE server machine, and the database or legacy machines at the back end. Three-tiered applications that run in this way extend the standard two-tiered client and server model by placing a multithreaded application server between the client application and back-end storage.

RMI Java Remote Method Invocation (Java RMI) enables the programmer to create distributed Java technology-based to Java technology-based applications, in which the methods of remote Java objects can be invoked from other Java virtual machines*, possibly on different hosts. RMI uses object serialization to marshal and unmarshal parameters and does not truncate types, supporting true object-oriented polymorphism.

Enterprise Resource Planning systems (ERPs) integrate (or attempt to integrate) all data and processes of an organization into a single unified system. A typical ERP system will use multiple components of computer software and hardware to achieve the integration. A key ingredient of most ERP systems is the use of a single, unified database to store data for the various system modules.

The term ERP originally implied systems designed to plan the utilization of enterprise-wide resources. Although the acronym ERP originated in the manufacturing environment, today's use of the term ERP systems has much broader scope. ERP systems typically attempt to cover all basic functions of an organization, regardless of the organization's business or charter. Business, not-for-profit organizations, governments, and other large entities utilize ERP systems. Additionally, it may be noted that to be considered an ERP system, a software package generally would only need to provide functionality in a single package that would normally be covered by two or more systems. Technically, a software package that provides both Payroll and Accounting functions (such as QuickBooks) would be considered an ERP software package. However; the term is typically reserved for larger, more broadbased applications. The introduction of an ERP system to replace two or more independent applications eliminates the need for interfaces previously required between systems, and provides additional benefits that range from standardization and lower maintenance (one system instead of two or more) to easier and/or greater reporting capabilities (as all data is typically kept in one database). Examples of modules in an ERP which formerly would have been standalone applications include: Manufacturing, Supply Chain, Financials, CRM, Human Resources, and Warehouse Management. Advantages In the absence of an ERP system, a large manufacturer may find itself with many software applications that do not talk to each other and do not effectively interface. Tasks that need to interface with one another may involve: • • • • •

design engineering (how best to make the product) order tracking from acceptance through fulfillment the revenue cycle from invoice through cash receipt managing interdependencies of complex Bill of Materials tracking the 3-way match between Purchase orders (what was ordered), Inventory receipts (what arrived), and Costing (what the vendor invoiced)

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the Accounting for all of these tasks, tracking the Revenue, Cost and Profit on a granular level.

Change how a product is made, in the engineering details, and that is how it will now be made. Effectivity dates can be used to control when the switch over will occur from an old version to the next one, both the date that some ingredients go into effect, and date that some are discontinued.Part of the change can include labeling to identify version numbers. Computer security is included within an ERP, to protect against both outsider crime, such as industrial espionage and insider crime, such as embezzlement. A data tampering scenario might involve a terrorist altering a Bill of Materials so as to put poison in food products, or other sabotage. ERP security helps to prevent abuse as well. There are concepts of Front office (how the company interacts with customers), which includes CRM or Customer relationship management; Back end (internal workings of the company to fulfill customer needs), which includes quality control, to make sure there are no problems not fixed, in the end products; Supply chain (interacting with suppliers and transportation infrastructure). All of these can be integrated through an ERP, although some systems have gaps in comprehensiveness and effectiveness. Without an ERP that integrates all these, it can be quite complicated for a manufacturer to handle. [edit] Disadvantages Many of the problems that organizations have with ERP systems are due to the inadequate level of investment in ongoing training for all personnel involved, including those implementing and testing changes, as well as a lack of corporate policies protecting the integrity of the data held in the ERP systems and how it is used. Limitations of ERP include: •

Success depends on the skill and experience of the workforce, including training about how to make the system work correctly. Many companies cut costs by cutting training budgets. Privately owned small enterprises are often undercapitalized, meaning their

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ERP system is often operated by personnel with inadequate education in ERP in general, such as APICS foundations, and in the particular ERP vendor package being used. Personnel turnover; companies can employ new managers lacking education in the company's ERP system, proposing changes in business practices that are out of synchronization with the best utilization of the company's selected ERP. Customization of the ERP software is limited. Some customization may involve changing of the ERP software structure which is usually not allowed. Re-engineering of business processes to fit the "industry standard" prescribed by the ERP system may lead to a loss of competitive advantage. ERP systems can be very expensive to install. ERP vendors can charge sums of money for annual license renewal that is unrelated to the size of the company using the ERP or its profitability. Technical support personnel often give replies to callers that are inappropriate for the caller's corporate structure. Computer security concerns arise, for example when telling a non-programmer how to change a database on the fly, at a company that requires an audit trail of changes so as to meet some regulatory standards. ERPs are often seen as too rigid, and difficult to adapt to the specific workflow and business process of some companies - this is cited as one of the main causes of their failure. Systems can be difficult to use. The system can suffer from the "weakest link" problem - an inefficiency in one department or at one of the partners may affect other participants. Many of the integrated links need high accuracy in other applications to work effectively. A company can achieve minimum standards, then over time "dirty data" will reduce the reliability of some applications. Once a system is established, switching costs are very high for any one of the partners (reducing flexibility and strategic control at the corporate level). The blurring of company boundaries can cause problems in accountability, lines of responsibility, and employee morale. Resistance in sharing sensitive internal information between departments can reduce the effectiveness of the software.

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There are frequent compatibility problems with the various legacy systems of the partners. The system may be over-engineered relative to the actual needs of the customer.

Oracle's PeopleSoft Enterprise Applications Oracle's PeopleSoft Enterprise applications are designed for the most complex business requirements. They provide web services integration with multivendor and homegrown applications and can be easily configured and adapted to meet the most unique customer requirements. In addition, PeopleSoft Enteprise supports a very broad choice of technology infrastructure. PeopleSoft Enterprise Human Capital Management Oracle's PeopleSoft Enterprise Human Capital Management unlocks the full value of your organization's workforce. PeopleSoft HCM enables you to put the right people in the right jobs, develop and reward top performers, retain key talent for the long term, and increase efficiency and operating performance throughout your organization. PeopleSoft HCM delivers on the four core HR business processes that can help you maximize the value you get from your workforce: AssessDesign-Develop, Optimize-Track-Monitor, Plan-Attract-Onboard, and Plan-IncentReward. PeopleSoft Human Capital Management is a family of applications in Oracle's PeopleSoft Enterprise product line. PeopleSoft Enterprise Performance Management Oracle's PeopleSoft Enterprise Performance Management (EPM) enables organizations to achieve world-class performance by aligning the right information and resources to strategic objectives.

PeopleSoft EPM offers performance management solutions for every budget and every phase of the management cycle, helping managers formulate strategies for profitable growth, align strategies with operational plans, actively monitor day-to-day operations, and collaborate across the enterprise. With the latest release of PeopleSoft EPM, customers gain real-time interactive profitability and planning tools, next-generation global compliance functionality, and rich packaged analytic content to speed application deployment. And EPM 8.9 is the first release that will have a supported migration path to Oracle Fusion and Oracle's adoption of a service-oriented architecture. Oracle and PeopleSoft As part of the integration of Oracle and PeopleSoft on June 1, 2005 we combined our two websites. All PeopleSoft.com content is now on Oracle.com. Below are some direct links to help you find what you're looking for. Learn more about the merger JD Edwards EnterpriseOne Oracle's JD Edwards EnterpriseOne is a complete suite of modular, preintegrated industry-specific business applications designed for rapid deployment and ease of administration. It is ideally suited for organizations that manufacture, construct, distribute, service, or manage products or physical assets. Get up and running fast with Oracle's JD Edwards EnterpriseOne Rapid Start, a complete solution of pre-configured software, services, hardware, and financing. ASSET LIFECYCLE MANAGEMENT CUSTOMER RELATIONSHIP MANAGEMENT FINANCIAL MANAGEMENT HUMAN CAPITAL MANAGEMENT

PROJECT MANAGEMENT SUPPLY CHAIN MANAGEMENT SUPPLY MANAGEMENT (PROCUREMENT) TOOLS AND TECHNOLOGY

BENEFITS Streamline processes: JD Edwards Customer Relationship Management applications support and streamline your entire business process from original customer contact through post-sales service. Seamless integration between solutions: JD Edwards EnterpriseOne Financial Management solutions are pre-integrated, and link seamlessly with all other JD Edwards EnterpriseOne solutions. Web-enabled applications delivered anywhere: Get rich, Web-enabled applications delivered to project professionals wherever the job takes them. Real-time collaboration: JD Edwards Supply Management (Procurement) enables you to manage your business process through real-time collaboration during design, demand, production, and distribution planning. Definition of: servlet A Java application that runs in a Web server or application server and provides server-side processing such as accessing a database and ecommerce transactions. Widely used for Web processing, servlets are designed to handle HTTP requests (get, post, etc.) and are the standard Java replacement for a variety of other methods, including CGI scripts, Active Server Pages (ASPs) and proprietary C/C++ plug-ins for specific Web servers (ISAPI, NSAPI). Because they are written in Java, servlets are portable between servers and operating systems. The servlet programming interface (Java Servlet API) is a standard part of the J2EE platform. If a Web server, such as Microsoft's Internet Information Server (IIS), does not run servlets natively, a third-party servlet plug-in can be installed to add the runtime support. See servlet container, Java, application server, JSP, J2EE, ISAPI, NSAPI and CGI script. What are Java Servlets? Servlets are Java technology's answer to CGI programming. They are programs that run on a Web server and build Web pages. Building Web pages on the fly is useful (and commonly done) for a number of reasons:

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The Web page is based on data submitted by the user. For example the results pages from search engines are generated this way, and programs that process orders for e-commerce sites do this as well. The data changes frequently. For example, a weather-report or news headlines page might build the page dynamically, perhaps returning a previously built page if it is still up to date. The Web page uses information from corporate databases or other such sources. For example, you would use this for making a Web page at an on-line store that lists current prices and number of items in stock.

What is JSP? Java Server Pages (JSP) is a technology that lets you mix regular, static HTML with dynamically-generated HTML. Many Web pages that are built by CGI programs are mostly static, with the dynamic part limited to a few small locations. But most CGI variations, including servlets, make you generate the entire page via your program, even though most of it is always the same. JSP lets you create the two parts separately. 4. What are the Advantages of JSP? •

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vs. Active Server Pages (ASP). ASP is a similar technology from Microsoft. The advantages of JSP are twofold. First, the dynamic part is written in Java, not Visual Basic or other MS-specific language, so it is more powerful and easier to use. Second, it is portable to other operating systems and non-Microsoft Web servers. vs. Pure Servlets. JSP doesn't give you anything that you couldn't in principle do with a servlet. But it is more convenient to write (and to modify!) regular HTML than to have a zillion println statements that generate the HTML. Plus, by separating the look from the content you can put different people on different tasks: your Web page design experts can build the HTML, leaving places for your servlet programmers to insert the dynamic content. vs. Server-Side Includes (SSI). SSI is a widely-supported technology for including externally-defined pieces into a static Web page. JSP is better because it lets you use servlets instead of a separate program to generate that dynamic part. Besides, SSI is really only intended for simple inclusions, not for "real" programs that use form data, make database connections, and the like.

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vs. JavaScript. JavaScript can generate HTML dynamically on the client. This is a useful capability, but only handles situations where the dynamic information is based on the client's environment. With the exception of cookies, HTTP and form submission data is not available to JavaScript. And, since it runs on the client, JavaScript can't access server-side resources like databases, catalogs, pricing information, and the like. vs. Static HTML. Regular HTML, of course, cannot contain dynamic information. JSP is so easy and convenient that it is quite feasible to augment HTML pages that only benefit marginally by the insertion of small amounts of dynamic data. Previously, the cost of using dynamic data would preclude its use in all but the most valuable instances.

Oracle Database 10g Oracle Database 10g is the first database designed for grid computing, the most flexible and cost-effective way to manage enterprise information. It cuts costs of management while providing the highest possible quality of service. In addition to providing numerous quality and performance enhancements, Oracle Database 10g significantly reduces the costs of managing the IT environment, with a simplified install, greatly reduced configuration and management requirements, and automatic performance diagnosis and SQL tuning. These and other automated management capabilities help improve DBA and developer productivity and efficiency. And with Release 2, Oracle's focus on improving efficiencies and reducing the cost of information management continues.

structs true to the literal meaning of the word, "Struts" provides supporting building blocks and infrastructure components to build a Web-based application. It is an MVC-based (Model View Controller) open source framework developed

and supported by the Apache Software Foundation. Because of its support for extensibility and plug-ins, the framework has picked up stupendous popularity among J2EE-based application developers. The framework can be extended and customized to suit a particular application need.

C# C is a simple , modern,object oriented language derived from c++ n java.it aims to combine the high productivity of visual basc and the raw power of c++.visul studio supports VB VC++,Vbscript n jscript.all of these laguages provide access to the Microsoft .net platform. .net include a common execution engine and a rich class library. It is developed by Microsoft

UNIX, which is a common operating system. By operating system, we mean the suite of programs which make the computer work. UNIX is used by the workstations and multi-user servers within the school. On X terminals and the workstations, X Windows provide a graphical interface between the user and UNIX. However, knowledge of UNIX is required for operations which aren't covered by a graphical program, or for when there is no X windows system, for example, in a telnet session. The UNIX operating system is made up of three parts; the kernel, the shell and the programs. The kernel The kernel of UNIX is the hub of the operating system: it allocates time and memory to programs and handles the filestore and communications in response to system calls. As an illustration of the way that the shell and the kernel work together, suppose a user types rm myfile (which has the effect of removing the file myfile). The shell searches the filestore for the file containing the program rm, and then requests the kernel, through system calls, to execute the

program rm on myfile. When the process rm myfile has finished running, the shell then returns the UNIX prompt % to the user, indicating that it is waiting for further commands. The shell The shell acts as an interface between the user and the kernel. When a user logs in, the login program checks the username and password, and then starts another program called the shell. The shell is a command line interpreter (CLI). It interprets the commands the user types in and arranges for them to be carried out. The commands are themselves programs: when they terminate, the shell gives the user another prompt (% on our systems). The adept user can customise his/her own shell, and users can use different shells on the same machine. Staff and students in the school have the tcsh shell by default. Everything in UNIX is either a file or a process. A process is an executing program identified by a unique PID (process identifier). A file is a collection of data. They are created by users using text editors, running compilers etc.

What JavaBeans is, and what it does JavaBeans is not a product, program, or development environment. It is both a core Java package (java.beans) that Beans may use to provided extended functionality, and a document (the JavaBeans Specification) that describes how to use the classes and interfaces in the java.beans package to implement "Beans functionality." The class specification is a part of the base release of Java 1.1, and so no additional software must be installed in order to use it. The addition of Beans required little change to the Java language per se, although several new and sorely-needed APIs were added to the core release to support Beans features. Reading the specification can be informative but soporific. Fortunately, it's optional if you already understand how and why to use the JavaBeans package. Perhaps you already understand Beans through reading an entertaining and enlightening series of articles on JavaBeans in JavaWorld, for example.

JavaBeans turns classes into software components by providing several new features. Some of these features are specific to Beans. Others, like serialization, can apply to any class, Bean or otherwise, but are crucial to the understanding and use of Beans. Software components have properties, which are attributes of the object. Customization is the process of configuring a Bean for a particular task. The new event handling scheme in Java 1.1 was created in part to ease communication between Beans. Beans may be dissected by IDEs or by other classes through a process called introspection. Beans may be persisted (i.e., serialized) into byte streams for transmission or storage, and persisted Beans may be packaged into "JAR files" to ease downloading and access. Finally, Beans have been designed to interoperate easily with legacy component technologies such as ActiveX and LiveConnect, and participate in transactions with Object Request Broker systems such as CORBA.

Tibco tibco - Tibco makes integration server software for enterprises. An integration server allows a company to mix packaged applications, custom software, and legacy software for use across internal and external networks. Tibco's patented approach is called Information Bus (TIB)and Tibco says that it has been used in financial services, telecommunications, electronic commerce, transportation, manufacturing, and energy. Tibco competes with SeeBeyond, Vitria, and webMethods among others. ActiveEnterprise is Tibco's integration server package that supports both message-bus and hub-and-spoke integration server models. The message-bus model connects the different applications to a common backbone using application adapters. The hub-and-spoke model connects all applications to a central server. Tibco's latest addition to ActiveEnterprise is BusinessWorks, which uses Web services technology. Tibco is based in Palo Alto, California and is traded (TIBX)on the Nasdaq.