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At present the computer world provides multiple platforms, going from Microsoft Windows,
Mackintosh, OS/2, Unix or Netware where the applications need to be compiled separately
for each one of these platforms. The resulting programs, generated for one particular
platform cannot be executed on a different platform as their binary files are structured
exclusively for this platform.
The Java platform, is a new software platform designed for providing and executing
applications interactively, dynamically and safely in a computing network environment.
But what is really impressive about the Java platform is that it sits on top of all
of these hardware related platforms and executes bytecodes that, as opposed to being
architecture specific, comprise instructions designed to be executed in a virtual machine.
A program created in Java, when compiled, converts to a bytecode that can be executed
in any virtual Java machine independent of the operating system functioning below. In
other words, the same binary file can be executed on any operating system that provides
a virtual Java machine. This portability is possible thanks to the fact that the core
of the Java platform is the virtual Java machine.
While distinct platforms related to different operating systems can implement their
own virtual Java machine, there is only one specification on the form this machine
should take. To this end the Java platform provides a single standard interface for
executing applications in any computer and on any operating system. In consequence the
Java platform is ideal for Internet, where programs should be capable of running on
any machine around the world. The Java platform has been designed to carry out its best
known slogan: "Once written, runs anywhere".
DEISTER SOFTWARE uses Java language for writing its applications. In this way they are compiled
just once on the Java platform, instead of for the operating system on each computer.
The source files are compiled to create an intermediate binary code that can be
executed on any machine comprising a Java platform.
Developers can write applications that are object oriented, multithread and dynamically
linked using Java language. The platform comprises of preinstalled safety systems,
exception management support and automatic memory recall. The Just-in-time compilers
are already available to improve execution times and convert the Java bytecodes to
specific machine code.
| The basic Java platform |  |
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The basic Java platform is the minimum platform that developers can be confident
will execute any application or Java applet. This platform is oriented towards
network computers, desktop computers and workstations. It comprises the already
mentioned virtual machine and a sub-group of all the APIs required to execute the
applications. This minimum sub-group is known as Java Applet API or Java Base API.
The developers who design their applications with this sub-group can be confident that
their application will execute in any computer without summoning additional directory
groups.
Another group of APIs exists called Standard Extension API, that has been defined
by Javasoft in co-operation with other companies in order to extend the basic function
and in the JDK 1.2 version has been fixed as the standard.
| Benefits of the Java platform | |
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The Java platform offers multiple benefits, not only for end-users but also for
developers and support personnel.
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The Java platform offers the possibility of accessing applications through the Web,
with instant access to programs. The applications are made available for executing
in any operating system from the start, freeing the users from having to choose a
certain operating system. By way of Java the smallest and cheapest computing systems
can be used for executing specialised applications.
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| | | Benefits for the developer |
The Java language is a reduced, well known and well documented API set. Developers
can write their applications just once for executing anywhere. In addition, the Java
development environments generate a single binary code on any operating system.
Instead of developing applications on multiple platforms, developers are able to
construct their applications on one single platform, so saving effort, and deliver
an application for one single platform that installs on all computers.
In addition to developing reusable and shared object oriented applications, it
reduces production costs allowing developers to concentrate on the creation of
objects for solving unexpected problems.
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| | | Benefits for the administrator |
The Java platform provides benefits for the company's system administration
departments. Version and update controls have been simplified as Java applications
are capable of maintaining themselves in a centralised location through which they
distributes to each user what he is going to use. In environments where applications
from various manufacturers come together and need to be executed on multiple platforms,
the number of platforms to be supported is reduced to one. The arrival of thin clients
potentially eliminates maintenance and upgrading costs.
Companies with an extensive intranet set-up might be of the opinion that it is of
no interest to them to update their whole computer installation with the latest,
in vogue, operating system that requires more memory. Instead, they can simply decide
to run Java applications on their existing equipment.
When applications are executed on a Java platform companies can take advantage of
the interactivity of Internet, transferring tasks, normally carried out by employees,
to their clients or suppliers. In this way companies can reduce the time spent on
entering an order by supplying their clients in the Web with order forms to be filled
in directly by them. This is already possible due to the use of standards, given that
the client will be able to use entry forms independently of the operating system being
used by his computer.
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| Why DEISTER uses Java technology? | |
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Given that the application servers are the best way of distributing applications,
services and data; what makes Java the best language for developing this type of
platform?. In fact, Java is the best platform for supplying application servers to
the consumer market and amongst the existing reasons we can elaborate on the following:
- It is an improvement on the traditional 3GL languages. Java is more simple
and high level than the traditional C++ language and also allows complex
programming problems to be easily dealt with.
- It is better than the 4GL languages. Java comprises multiple library classes
and is easily extensible with reusable business rules at high level.
- It is universal. Where there is a client connected to the network Java is there.
- It is mature. Java has come of age in both velocity and performance with
a powerful and flexible development and execution environment.
- It is robust. Its sturdiness guarantees the most dependable and safe generation
of applications as it incorporates features that reduce development and set-up time.
- It's interpreted
- Suffers no memory loss
- No memory access errors
- With the integration of multiple components problems can more easily
be diagnosed
- Java has been designed with the Web in mind right from the start.
- It's rapid. The arrival of new virtual machines and new technologies has
allowed Java to reduce the difference in execution time between Java and C++
applications. That being so, in fact 60-80% of the CPU time is normally taken
up with database querying, and another 5-15% with the network. That means that
CPU time required for the execution of Java applications is minimum compared to
that required by other applications; and the tiny difference is velocity is
hardly noticeable these days.
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