Saturday, July 31, 2010

JAVA : object-oriented,distributed, interpreted, robust, secure,architecture-neutral, portable, multithreaded, dynamic,buzzword-compliant, general-purpose programming language

A simple, object-oriented,distributed, interpreted, robust, secure,architecture-neutral, portable, multithreaded, dynamic,buzzword-compliant, general-purpose programming language developed by Sun Microsystems in 1995(?). Java supportsprogramming for the Internet in the form ofplatform-independent Java "applets".

Java is similar to C++ without operator overloading(though it does have method overloading), without multipleinheritance, and extensive automatic coercions. It has automatic garbage collection.

Java programs can run stand-alone on small computers. The interpreter and class support take about 40 kilobytes;adding the standard libraries and thread support (essentially a self-contained microkernel) adds an additional 175Kb.

Java extends C++'s object-oriented facilities with those of Objective C for dynamic method resolution.

Java has an extensive library of routines for TCP/IP protocols like HTTP and FTP. Java applications can access objects across the Internet via URLs as easily as on the local file system.

The Java compiler and linker both enforce strong type checking - procedures must be explicitly typed. Java supports the creation of virus-free, tamper-free systems with authentication based on public-key encryption.

The Java compiler generates an architecture-neutral object file executable on any processor supporting the Java run-time system. The object code consists of bytecode instructions designed to be both easy to interpret on any machine and easily translated into native machine code at load time.

The Java libraries provide portable interfaces. For example, there is an abstract Window class and implementations of it for Unix, Microsoft Windows and the Macintosh. The run-time system is written in POSIX-compliant ANSI C. Java applets can be executed as attachments in World-Wide Web documents using either Sun's HotJava browser or Netscape Navigator version 2.0.

Java operating program that sits on top of a computer's operating system and runs Java applets and other Java programs. Called virtual machine because the environment it creates for executing the Java code behaves like a computer separate from the one it is running on, and can be installed or removed without interfering with the computer's operating system.

A common phrase attributed to Java is "Write Once, Run Anywhere" - the JVM is a core component to that philosophy. It executes compiled Java programs regardless of the hardware or software platform it is installed on.

The power of the JVM is such that it can now execute compiled programs written in many other languages (e.g, C/C++ , Ruby, Javascript, PHP, Python , Scala, and many more).

HostingPalace has the innovative webhosting technology to implement in the web hosting domestic market. The web hosting Panel provided by HostingPalace as control panel of your domain is one among the best in the current market. It is your domain control panel, from where you manage all aspects of your domain and its contents. The domain control panel provided by web hosting company has been designed with the intention of making it easier for an individual to even act as a domain registrar possessing an authority to register a domain for self or for its clients and every now and then on the basis of requirement he can modify the web hosting account with every new update hence the domain resellers can benefit from such technology with the authority to register domain for its clients. It has become more user-friendly and more reliable.

When you access your web hosting account, everything you need is available right there in hosting panel or domain control panel itself.

The main tools available within your panels let you do the basic domain and webspace administration required to keep your website in order. You can set or reset your login details, ftp details and email accounts from web hosting control panel. You can access and maintain all your databases from your web hosting control panel as well, review basic statistics of your website, check your bandwidth use, check which scripts are supported, block certain IP addresses(depends on the web hosting package terms) from accessing your website, check for and clear up viruses, make a backup of your entire site, and other general maintenance actions, or grooming, of your domain.

If your web hosting plan allows it, you can actually set up different domains within your single account and control them all through your hosting or domain control panel.

Within your webhosting panel, you will more often than not find a handy little extra applications called file manager. It is what made easier for a client to deploy website files in webspace without taking the help of ftp account.Inbuilt feature of webhosting panel helps doing so, and this brilliant tool really comes as a handy element for hosting resellers who in this case every now and then need not have to memorize or search for ftp login information for different domains of its clients . It is not restricted to limited upload or download. One can deploy unlimited files in its webspace using the feature however restricted to limited upload in some online software at one time due to unavailability to browse for unlimited files. Bandwidth doesnt get much affected with such move and unlimited upload and download can easily be taken into process(incase the package has unlimited webspace and bandwidth facility).

Some hosting panel has the feature of adding java applications separately to its webspace package. As java is an important and widely used application most of the web hosting companies will make it sure the compatible features to enable the java application resides in the online software or control panel.

Many web hosting companies have added online shopping application in its webspace packages which helps clients to add up the application to its website at ease rather swaying the process of manipulation and editing. These comes free nowadays with web hosting packages. Most of the web hosting companies have included such applications for free in its web hosting package to let their client get benefited for hosting web applications.

HostingPalace has started providing free search engine submission for its 2 years old clients.Based on the demand of our clients which they are looking to get for free along with their web hosting i.e webspace packages HostingPalace has stated implementing this technique to help our clients to submit their website URL for free in over 8 lakh search engines.

When a website is created, the domain name and the web hosting are the two main things which need to be taken care of. While getting the domain name is simple and easy, it is the webhosting that possesses a bigger challenge. Now, when a computer needs to be made to be running as the web server, it needs to have the web server software running, which delivers the web pages to the clients using protocols like Hypertext Transfer Protocol (HTTP) over the World Wide Web. These software packages actually work like running a virtual machine or a computer which process the requests continuously and act as the web servers. There are many different software options to run the web servers like IIS, Jakarta Tomcat, Apache etc. which can simulate a web server.

Since not all of these are supported on all different platforms, it is important to decide which platform is being selected for the machine that will act as the web server and also install the corresponding web server software. One of the generic and supported web server solutions, which work on both Linux and Windows, is the Jakarta Tomcat software solution. Tomcat is basically a servlet hosting component, originally written by Sun Microsystems and later donated by them to Apache Software Foundation. The beauty of Tomcat is that it seamlessly integrates with both Apache httpd and Microsoft's IIS (Internet Information Services) server, which makes it platform independent.

Let us first begin by knowing what exactly is a servlet and where does Tomcat fit. To start right at the beginning, there are 2 types of websites – static and dynamic. Static websites are those, which are simply html pages served over the network. They are very limited in terms of logic and user intractability. A little bit of dynamism that can be added to such static pages is through client side scripting languages such as JavaScript. These however, are limited in their capabilities. Dynamic web pages are those which are more intelligent. They "remember" users who return to the website. They allow users to customize their viewing options and remember a multitude of things for them. Such websites have a server which contains programs such that these programs are executed on the server and the results of these programs are displayed to the user. In most of the cases, and in all Java based websites, a servlet is used to provide this intelligence. A servlet is a basic Java class which resides on the server and allows the site to indulge in dynamic content. It is the logic which powers dynamism in a web site. Thus, it has 2 interaction streams - a request stream, where it tracks the user's choices and a response stream, where it responds back to the user. Closely related to a servlet is a Java Servlet Page, JSP, which is nothing but a combination of the static HTML pages and the dynamic Java code.

Given this basic knowledge, we are now in a position to understand Tomcat. Tomcat is the environment where these JSPs and Servlets can execute. Tomcat, is thus, a part of the web server, and it is the place where the programming logic of the dynamic website resides and executes. Along with providing the execution environment, Tomcat also provides programmers flexibility in terms of class loading and management, session management etc. Using Tomcat, the programmers can afford to focus only on the logic and forget about lower level administrative overheads. Tomcat provides a rich Application Programming Interface, API, which the developers liberally use during the development of the application.

Tomcat is an open source container and is freely available from the apache website as source code as well as in binary format. The installation is really very simple and it requires a Java JDK (Java Developer's Kit) installation as a pre-requisite. The installation is slightly different on Windows and UNIX. Details of this can be found at the help pages on the official Tomcat site: http://tomcat.apache.org

In the current era where the machines have grown faster and faster, hosting only a single domain name from a web server may be considered as a waste of resources. As a result, there is a new concept called Virtual hosting. Virtual hosting is a way through which multiple domain names can be hosted on a single server via a single IP address and hence turns out to be more economical in the sense of utilization of resources. Tomcat allows for virtual hosting in a very simple and lucid manner. All it requires adding the <host> tag with proper name and directory path relative to the home directory in the server.xml file of the installation.

Owning to the above features, Tomcat is one of the most widely used and recommended product. In case you are planning to get yourself a web hosting service, check out whether they offer the Tomcat Hosting solution.

You're in complete control of your server. With private Java hosting, each Tomcat server runs in its own memory space. You control everything that happens there, including stopping and starting the server, which, if available at all in a shared environment, usually requires a work ticket to tech support.

In addition, if someone in a shared environment has a memory leak or code that's a high user of memory, everyone sharing that JVM suffers the same memory problems. These can range from server slowdowns to out of memory exceptions that freeze the server - usually until a human notices the problem and restarts the engine.

Another thing is that anyone causing security problems within a shared JVM, whether by intent or not, puts every other user at risk. Tomcat is a very secure server with finely grained controls

With millions of developers worldwide, Java is the most popular programming language in use today. You can use Java to create everything from applications for cell phones and PDAs, to desktop applications and distributed enterprise applications that execute on many platforms. Java can run on hardware from the smallest devices (such as chips embedded in credit cards) to the largest supercomputers. Our Java Resource Center focuses on the enormous amount of Java free content available online. Start your search here for resources, downloads, tutorials, documentation, books, e-books, journals, articles, blogs and more that will help you develop Java applications.

Welcome to the Java Design Patterns Resource Center. In their book, Design Patterns, Elements of Reusable Object-Oriented Software, the "Gang of Four" (E. Gamma, R. Helm, R. Johnson, and J. Vlissides) describe 23 design patterns that provide proven architectures for building object-oriented software systems. In this resource center, you'll find discussions of many of these design patterns. You'll also learn how Java API packages take advantage of design patterns. The Java Design Patterns Resource Center includes links to:

Java Design Patterns tutorials.
Several Java Design Patterns books sample chapters including "Introduction to Design Patterns," from Design Patterns Java Workbook, by Steven John Metsker, and "Design Patterns: Origin and History," from Software Architecture Design Patterns in Java, by Partha Kuchana.
A slide presentation entitled "Using Design Patterns in Java Application Development," by Michael P. Redlich.
The article: "What Are Design Patterns?" by James W. Cooper.
The Java Patterns and Object Oriented Design forum.
Sun Microsystems Java Patterns page that includes patterns and code for Java applications.
The Java BluePrints Patterns catalog.
The J2EE Patterns mailing list.
Download the Java Design Patterns API.
"Overview of Design Patterns," from Design Patterns in Java: A Catalog of Reusable Design Patterns Illustrated with UML, Second Edition, by Mark Grand.
The J2EE patterns catalog, including sample code from the Java BluePrints catalog.
Definitions and examples of many Java design patterns.
Design patterns articles by David Geary.
Sample discussions from Design Patterns: Elements of Reusable Object-Oriented Software, January 1995, by Erich Gamma, Richard Helm, Ralph Johnson and John Vlissides (available in the Rice University site).
The free eBook, The Design Patterns Java Companion, by James W. Cooper.
Java Design Patterns training courses, books and eBooks.
Job sites where you can search for Java software development jobs.
Pattern Languages of Programming (PLoP) Conferences in the USA and Europe.

The Java Enterprise Edition 5 (Java EE 5) Resource Center is your guide to the latest release of Java Enterprise Edition. It includes the best online resources to help you get started with Java Enterprise Edition 5 (Java EE 5) development. In our Java Enterprise Edition 5 (Java EE 5) Resource Center you'll find:

Java EE resources from Sun Microsystems, including articles, tutorials, the latest Java Platform Enterprise Edition 5 Specification and more.
The Java EE 5 tools download that includes NetBeans IDE 5.5 Beta, NetBeans Enterprise Pack 5.5 Early Access, Sun Java System Application Server Platform Edition 9, Project Open ESB Starter Kit Beta, Sun Java System Access Manager 7.1, Java EE 5 Samples, Java BluePrints, and API docs (Javadoc).
Downloads of Java EE sample applications demonstrating Enterprise JavaBeans 3.0, web services, JAXB, JNDI, JDBC, security and more.
Enterprise Java Beans 3.0 resources including the specification, an overview of the EJB 3.0 API, sample chapters and books.
Resources for the Java API for XML-based Web Services (JAX-WS) 2.0, including the JAX-WS 2.0 specification, tutorials and articles.
The "Introduction to Java EE 5 Technology" tutorial from NetBeans.org.
GlassFish (an open source Java EE 5 application server) projects including frameworks, applications, interoperability techniques, and tools.
The JavaServer Pages specification, plus Java Server Pages articles, white papers and books.
A slide presentation that walks through the features of the Java EE.
Links to the Java EE 5 forums at Sun Microsystems.
Information about the Java Persistence API, including FAQs, blog entries, tutorials and articles.
AJAX resources. Also, check out our AJAX Resource Center.
JavaServer Faces articles that provide an introduction to JavaServer Faces, the JSF components and AJAX-enabled JSF components.
Unified Expression Language (EL) downloads and articles.
Java EE 5 articles, podcasts, sample chapters, books, job postings and more.

The JavaScript scripting language was originally developed by Netscape in December 1995, and is commonly used in web applications. We present key server-side scripting languages in our Perl, Python and PHP Resource Centers. This resource center presents JavaScript, which is the most widely used client-side scripting language. JScript is Microsoft's version of JavaScript. Both JavaScript and JScript have at their core the ECMA-262 Edition 3 and ECMAScript standard version 4, respectively. JavaScript is a mature language which now has a huge complement of support tools, documentation, free code generators, libraries and more.

HostingPalace is a famous web hosting service providers who can support Linux & Windows server. You can get Java web hosting starts in an affordable price from this reliable and trusted web hosting company.

For fast, secure and reliable Tomcat, JSP, and Java Hosting, look no further than HostingPalace for all your web hosting related needs. The following plan provides everything you need, including full accessibility to Tomcat, JSP, and Java Servlet, to get you up and running within minutes.

Java is a programming language and computing platform first released by Sun Microsystems in 1995. It is the underlying technology that powers state-of-the-art programs including utilities, games, and business applications. Java runs on more than 850 million personal computers worldwide, and on billions of devices worldwide, including mobile and TV devices.

There are lots of applications and websites that won't work unless you have Java installed, and more are created every day. Java is fast, secure, and reliable. From laptops to datacenters, game consoles to scientific supercomputers, cell phones to the Internet, Java is everywhere!

The latest Java version contains important enhancements to improve performance, stability and security of the Java applications that run on your machine. Installing this free update will ensure that your Java applications continue to run safely and efficiently.

The Java Runtime Environment (JRE) is what you get when you download Java software. The JRE consists of the Java Virtual Machine (JVM), Java platform core classes, and supporting Java platform libraries. The JRE is the runtime portion of Java software, which is all you need to run it in your Web browser. When you download Java software, you only get what you need - no spyware, and no viruses.

The Java Plug-in software is a component of the Java Runtime Environment (JRE). The JRE allows applets written in the Java programming language to run inside various browsers. The Java Plug-in software is not a standalone program and cannot be installed separately.

The Java Virtual Machine is only one aspect of Java software that is involved in web interaction. The Java Virtual Machine is built right into your Java software download, and helps run Java applications.

Dynamic website design has gotten a whole lot simpler recently with the introduction of the JSP framework – an easier-to-use relative of industry standard, Java. JSP, developed by Sun Microsystems, delivers all of the benefits of Java language in an easy-to-learn, easier-to use format so you get all of the benefits of Java without all of the headaches (and expense associated with hiring a Java programmer).

Not all Web Hosting are JSP capable, in part because of required server software upgrades and the usual learning curve. The techs at many hosting companies are just starting to learn how to use JSP and Java Servlets, keeping their clients from growing the dynamic, active, feature-deep web sites that web users expect today.

JSP Web Hosting is a powerful option, and an ideal choice for those looking to publish a JSP-coded website. Java hosting, and JSP Web Hosting in particular, is also a top choice among designers working in a team.

JSP Web Hosting is one of the many Java hosting options web developers have at their disposal, facilitating efficient management of Java Server Pages. We've made the hunt for a Java hosting company easier with our Top picks for JSP Web hosting companies.

Actually, the 2 languages have almost nothing in common except for the name. Although Java is technically an interpreted programming language, it is coded in a similar fashion to C++, with separate header and class files, compiled together prior to execution. It is powerful enough to write major applications and insert them in a web page as a special object called an "applet." Java has been generating a lot of excitment because of its unique ability to run the same program on IBM, Mac, and Unix computers. Java is not considered an easy-to-use language for non-programmers.

Javascript is much simpler to use than Java. With Javascript, if I want check a form for errors, I just type an if-then statement at the top of my page. No compiling, no applets, just a simple sequence.

Everyone that wants to program JavaScript should at least try reading the following section. If you have trouble understanding it, don't worry. The best way to learn JavaScript is from the examples presented in this tutorial. After you have been through the lessons, come back to this page and read it again.

OOP is a programming technique (note: not a language structure - you don't even need an object-oriented language to program in an object-oriented fashion) designed to simplify complicated programming concepts. In essence, object-oriented programming revolves around the idea of user- and system-defined chunks of data, and controlled means of accessing and modifying those chunks.

Object-oriented programming consists of Objects, Methods and Properties. An object is basically a black box which stores some information. It may have a way for you to read that information and a way for you to write to, or change, that information. It may also have other less obvious ways of interacting with the information.

Some of the information in the object may actually be directly accessible; other information may require you to use a method to access it - perhaps because the way the information is stored internally is of no use to you, or because only certain things can be written into that information space and the object needs to check that you're not going outside those limits.

The directly accessible bits of information in the object are its properties. The difference between data accessed via properties and data accessed via methods is that with properties, you see exactly what you're doing to the object; with methods, unless you created the object yourself, you just see the effects of what you're doing.

Other Javascript pages you read will probably refer frequently to objects, events, methods, and properties. This tutorial will teach by example, without focusing too heavily on OOP vocabulary. However, you will need a basic understanding of these terms to use other JavaScript references.

Your web page document is an object. Any table, form, button, image, or link on your page is also an object. Each object has certain properties (information about the object). For example, the background color of your document is written document.bgcolor. You would change the color of your page to red by writing the line: document.bgcolor="red"

The contents (or value) of a textbox named "password" in a form named "entryform" is document.entryform.password.value.

Most objects have a certain collection of things that they can do. Different objects can do different things, just as a door can open and close, while a light can turn on and off. A new document is opened with the method document.open() You can write "Hello World" into a document by typing document.write("Hello World") . open() and write() are both methods of the object: document.

Events are how we trigger our functions to run. The easiest example is a button, whose definition includes the words onClick="run_my_function()". The onClick event, as its name implies, will run the function when the user clicks on the button. Other events include OnMouseOver, OnMouseOut, OnFocus, OnBlur, OnLoad, and OnUnload.



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